/* 响应式与版式覆盖：先手机基础，再视觉修正及平板横竖屏规则。 保留分区注释，避免再新增重复覆盖文件。 */

/* ===== 原模块：mobile-layout.css ===== */
/* 手机布局和导航覆盖；与页面专用样式共同生效。修改时保留页面中样式表的加载顺序。 */
/* Phone-only layout. Desktop styling remains with the existing stylesheets. */
.mobile-nav-toggle { display: none; }
@media (max-width: 620px) {
  body.playful-site.academic-site { font-size: 16px; }
  body.playful-site.academic-site.home-page { font-size: 15px; }
  body.playful-site.academic-site :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    padding-inline: 18px; gap: 10px;
  }
  body.playful-site.academic-site :is(.site-header, .algebra-header) { height: 88px; }
  body.playful-site.academic-site .simple-header { min-height: 88px; padding-block: 8px; }
  body.playful-site.academic-site :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    height: 72px; width: auto; max-height: 72px;
  }
  body.playful-site.academic-site .simple-header > .button { padding: 10px 12px; font-size: 14px; min-height: 44px; }
  body.playful-site.academic-site .mobile-nav-toggle {
    display: grid; place-content: center; gap: 5px; flex: 0 0 44px;
    width: 44px; height: 44px; padding: 10px; border: 1px solid #dce5ef;
    border-radius: 6px; background: transparent; color: #182f4d; cursor: pointer;
  }
  .mobile-nav-toggle span { display: block; width: 21px; height: 2px; background: currentColor; }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav { display: none; }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav.mobile-nav-open {
    display: grid; grid-template-columns: 1fr; order: 5; width: 100%;
    gap: 0; padding: 8px 0; max-height: 60dvh; overflow-y: auto;
    overscroll-behavior-y: contain; text-align: left;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav a {
    display: flex; align-items: center; min-height: 44px; padding: 10px 12px;
    font-size: 16px; white-space: normal; border-radius: 4px;
  }
  body.playful-site.academic-site :is(.hero, .page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    padding: 36px 20px; gap: 28px;
  }
  body.playful-site.academic-site :is(.hero .home-hero-title, .page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1) {
    font-size: clamp(28px, 8vw, 34px); line-height: 1.2; margin-block: 14px 20px;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(28px, 7.8vw, 32px); line-height: 1.15; margin: 12px 0 16px;
  }
  body.playful-site.academic-site :is(.hero-lead, .hero-description, .page-hero > p:not(.kicker), .content-hero > p:not(.kicker)) {
    font-size: 16px; line-height: 1.7;
  }
  body.playful-site.academic-site.home-page .hero-lead { font-size: 15px; line-height: 1.65; }
  body.playful-site.academic-site :is(.page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) > .kicker {
    font-size: 13px; line-height: 1.6; letter-spacing: .08em; margin-top: 0;
  }
  body.playful-site.academic-site :is(.section, .page-wrap, .content-wrap, .competition-section, .trial) { padding: 40px 20px; }
  body.playful-site.academic-site :is(.page-intro, .section-heading) { gap: 16px; margin-bottom: 26px; }
  body.playful-site.academic-site .page-intro > p { margin: 0; }
  body.playful-site.academic-site :is(.page-intro h2, .section-heading h2, .home-pathways .section-heading h2, .program-copy h2, .contest-heading h2) {
    font-size: clamp(25px, 7vw, 30px); line-height: 1.25;
  }
  body.playful-site.academic-site.home-page :is(.v2-heading h2, .section-heading h2, .home-pathways .section-heading h2) {
    font-size: clamp(24px, 6.6vw, 28px); line-height: 1.22;
  }
  body.playful-site.academic-site :is(.program-card, .home-pathways .program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .trial-form, .inquiry-form) {
    padding: 22px; min-width: 0;
  }
  body.playful-site.academic-site .home-pathways .program-card h3 { min-height: 0; font-size: 24px; }
  body.playful-site.academic-site.home-page :is(.home-pathways .program-card h3, .v2-program-grid h3) { font-size: 22px; }
  body.playful-site.academic-site.home-page :is(.v2-program-grid p, .section-heading > p, .system-summary p) { font-size: 15px; }
  body.playful-site.academic-site.home-page .hero-actions .button { font-size: 15px; }
  body.playful-site.academic-site :is(.program-grid, .info-grid, .content-grid, .pathway-cards, .stage-grid) { gap: 20px; }
  body.playful-site.academic-site :is(.hero-actions, .a-actions) { gap: 12px; }
  body.playful-site.academic-site .hero-actions > a { width: 100%; text-align: center; justify-content: center; }
  body.playful-site.academic-site :is(.subject-jump, .competition-jump) { gap: 8px; }
  body.playful-site.academic-site :is(.subject-jump, .competition-jump) a { min-height: 44px; display: inline-flex; align-items: center; padding: 8px 12px; }
  body.playful-site.academic-site .inquiry-form { margin-top: 28px; }
  body.playful-site.academic-site .inquiry-form a { overflow-wrap: anywhere; }
  body.playful-site.academic-site .course-group .course-card { padding: 0; grid-template-columns: minmax(0, 1fr); }
  body.playful-site.academic-site .course-group .course-copy { padding: 22px 20px 12px; min-width: 0; }
  body.playful-site.academic-site .course-group .course-card h4 { overflow-wrap: break-word; }
  body.playful-site.academic-site .course-group .course-fee { padding: 0 20px 18px; text-align: left; }
  body.playful-site.academic-site :is(input:not([type=checkbox]):not([type=radio]):not([type=hidden]), select) { min-height: 44px; }
  body.playful-site.academic-site .site-header ~ main[id],
  body.playful-site.academic-site .site-header ~ main [id] { scroll-margin-top: 104px; }
  body.playful-site.academic-site .footer-main { gap: 28px; }
  body.playful-site.academic-site .site-footer { padding: 36px 20px 24px; }

  /* Homepage phone composition: compact header, calmer hero, and lighter content rhythm. */
  body.playful-site.academic-site.home-page .announcement {
    height: 32px; min-height: 32px; padding-inline: 14px; font-size: 12px;
  }
  body.playful-site.academic-site.home-page .site-header {
    height: 70px; padding-inline: 16px; gap: 12px;
  }
  body.playful-site.academic-site.home-page .site-header picture .brand-logo {
    width: 124px; height: auto; max-height: 52px;
  }
  body.playful-site.academic-site.home-page .menu-toggle {
    width: 42px; min-width: 42px; height: 42px; min-height: 42px; padding: 8px;
  }
  body.playful-site.academic-site.home-page .hero {
    padding: 32px 18px 38px; gap: 0;
  }
  body.playful-site.academic-site.home-page .hero .eyebrow {
    font-size: 11px; line-height: 1.5; letter-spacing: .07em;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title::after {
    width: 44px; height: 3px; margin-top: 16px;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    max-width: 350px; font-size: 28px; line-height: 1.14;
  }
  body.playful-site.academic-site.home-page .home-hero-title .hero-title-phrase {
    display: inline; white-space: normal;
  }
  body.playful-site.academic-site.home-page .hero-actions {
    align-items: center; margin-top: 22px;
  }
  body.playful-site.academic-site.home-page .hero-actions .button {
    min-height: 46px; padding: 12px 16px;
  }
  body.playful-site.academic-site.home-page .hero-actions .button span { margin-left: 6px; }
  body.playful-site.academic-site.home-page .hero-actions .text-link {
    width: auto; padding-block: 6px; font-size: 14px;
  }
  body.playful-site.academic-site.home-page .hero-problem {
    display: none;
  }
  body.playful-site.academic-site.home-page .problem-card {
    padding: 18px; border-top-width: 2px;
  }
  body.playful-site.academic-site.home-page .problem-top,
  body.playful-site.academic-site.home-page .problem-label,
  body.playful-site.academic-site.home-page .problem-foot { font-size: 11px; }
  body.playful-site.academic-site.home-page .problem-card h2 {
    font-size: 16px; line-height: 1.45;
  }
  body.playful-site.academic-site.home-page .answer-row {
    gap: 6px; margin: 17px 0;
  }
  body.playful-site.academic-site.home-page .answer-row span {
    padding-block: 8px; font-size: 13px;
  }
  body.playful-site.academic-site.home-page :is(.v2-programs, .v2-system, .section) {
    padding: 44px 18px;
  }
  body.playful-site.academic-site.home-page .v2-heading { margin-bottom: 24px; }
  body.playful-site.academic-site.home-page .v2-program-grid { gap: 14px; }
  body.playful-site.academic-site.home-page .v2-program-grid > a {
    display: grid; grid-template-columns: 28px minmax(0, 1fr); column-gap: 12px;
    padding: 17px 18px; border-top-width: 3px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid > a > span {
    grid-row: 1 / 4; align-self: start; padding-top: 2px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid h3 {
    margin: 0 0 9px; padding-bottom: 10px; font-size: 20px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid p {
    min-height: 0; margin: 0 0 10px; font-size: 14px; line-height: 1.55;
  }
  body.playful-site.academic-site.home-page .v2-program-grid b { font-size: 13px; }
  body.playful-site.academic-site.home-page .v2-programs > p {
    margin: 20px 0 0; font-size: 14px; line-height: 1.5;
  }
  body.playful-site.academic-site.home-page :is(.home-pathways .program-card, .story-grid blockquote) {
    padding: 18px;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    min-height: 0; margin-top: 16px;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card > p:not(.grade) {
    margin-bottom: 12px; line-height: 1.55;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 {
    margin-block: 12px 10px; padding-bottom: 12px;
  }
  body.playful-site.academic-site.home-page .pathway-details summary {
    min-height: 42px; padding-block: 10px; font-size: 14px;
  }
  body.playful-site.academic-site.home-page .pathway-primary {
    min-height: 44px; padding: 10px 14px; font-size: 14px;
  }
  body.playful-site.academic-site.home-page .v2-five {
    grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; margin-bottom: 20px;
  }
  body.playful-site.academic-site.home-page .v2-five > article {
    padding: 15px; border: 1px solid #d6e1ed;
  }
  body.playful-site.academic-site.home-page .v2-five > article:last-child {
    grid-column: 1 / -1;
  }
  body.playful-site.academic-site.home-page .v2-five h3 {
    margin: 10px 0 4px; font-size: 17px;
  }
  body.playful-site.academic-site.home-page .v2-five :is(strong, p) {
    font-size: 12px; line-height: 1.5;
  }
  body.playful-site.academic-site.home-page .method-copy {
    padding: 32px 20px;
  }
  body.playful-site.academic-site.home-page .method-list {
    gap: 16px; margin-top: 24px;
  }
  body.playful-site.academic-site.home-page .method-list > div { padding-top: 12px; }
  body.playful-site.academic-site.home-page .story-grid {
    grid-template-columns: none; grid-auto-flow: column;
    grid-auto-columns: minmax(276px, 84vw); gap: 12px;
    margin-inline: -18px; padding: 2px 18px 16px;
    overflow-x: auto; overscroll-behavior-inline: contain;
    scroll-snap-type: inline mandatory; scrollbar-width: none;
  }
  body.playful-site.academic-site.home-page .story-grid::-webkit-scrollbar { display: none; }
  body.playful-site.academic-site.home-page .story-grid > blockquote { scroll-snap-align: start; }
  body.playful-site.academic-site.home-page .stories { overflow: hidden; }
  body.playful-site.academic-site.home-page .stories .section-heading { margin-bottom: 18px; }
  body.playful-site.academic-site.home-page .stories .section-heading > p { font-size: 14px; }
  body.playful-site.academic-site.home-page .footer-main { gap: 22px; }
  body.playful-site.academic-site.home-page .footer-main > div { gap: 7px; }
  /* 手机课程标签明确上下排列，避免 display:block 下两个内联元素粘连。 */
  body.playful-site.academic-site.home-page .stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    padding: 0 16px;
  }
  body.playful-site.academic-site.home-page .stats > div {
    display: flex;
    flex-direction: column;
    flex-wrap: nowrap;
    justify-content: center;
    align-items: center;
    gap: 8px;
    min-width: 0;
    min-height: 116px;
    padding: 18px 12px;
    text-align: center;
    border-right: 0;
  }
  body.playful-site.academic-site.home-page .stats > div:nth-child(odd) { border-right: 1px solid var(--line); }
  body.playful-site.academic-site.home-page .stats > div:nth-child(n+3) { border-top: 1px solid var(--line); }
  body.playful-site.academic-site.home-page .stats strong { display: block; font-size: 22px; line-height: 1.2; white-space: nowrap; }
  body.playful-site.academic-site.home-page .stats span { display: block; max-width: 100%; font-size: 13px; line-height: 1.5; word-break: normal; overflow-wrap: normal; }
  body.playful-site.academic-site.home-page .story-grid blockquote p { font-size: 15px; line-height: 1.65; }
  body.playful-site.academic-site.home-page .site-header ~ main[id],
  body.playful-site.academic-site.home-page .site-header ~ main [id] { scroll-margin-top: 84px; }
  body.playful-site.academic-site.home-page .site-footer { padding: 32px 18px 22px; }

  /* Reduced homepage type scale for compact phone screens; touch targets stay unchanged. */
  body.playful-site.academic-site.home-page { font-size: 14px; }
  body.playful-site.academic-site.home-page .announcement { font-size: 11px; }
  body.playful-site.academic-site.home-page .hero .eyebrow { font-size: 10px; }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    max-width: 330px; font-size: 26px; line-height: 1.16;
  }
  body.playful-site.academic-site.home-page .hero-lead { font-size: 14px; line-height: 1.62; }
  body.playful-site.academic-site.home-page :is(.v2-heading h2, .section-heading h2, .home-pathways .section-heading h2, .method h2) {
    font-size: 23px; line-height: 1.2;
  }
  body.playful-site.academic-site.home-page :is(.hero-actions .button, .hero-actions .text-link, .pathway-primary) {
    font-size: 13px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid h3 { font-size: 18px; }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 { font-size: 20px; }
  body.playful-site.academic-site.home-page :is(.v2-program-grid p, .section-heading > p, .home-pathways .program-card > p:not(.grade), .method-copy > p, .story-grid blockquote p, .system-summary p) {
    font-size: 14px;
  }
  body.playful-site.academic-site.home-page :is(.grade, .pathway-details summary, .home-pathways .program-card li, .v2-programs > p) {
    font-size: 13px;
  }
  body.playful-site.academic-site.home-page .story-grid blockquote h3 { font-size: 16px; }
  body.playful-site.academic-site.home-page :is(.footer-main, .footer-bottom) { font-size: 13px; }

  /* Final compact scale: typography and spacing reduce together. */
  body.playful-site.academic-site.home-page { font-size: 13px; }
  body.playful-site.academic-site.home-page .announcement {
    height: 30px; min-height: 30px; font-size: 10.5px;
  }
  body.playful-site.academic-site.home-page .site-header {
    height: 66px; padding-inline: 15px;
  }
  body.playful-site.academic-site.home-page .site-header picture .brand-logo {
    width: 118px; max-height: 48px;
  }
  body.playful-site.academic-site.home-page .hero {
    padding: 27px 16px 32px;
  }
  body.playful-site.academic-site.home-page .hero .eyebrow { font-size: 9.5px; }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    max-width: 340px; margin-block: 10px 14px; font-size: 24px; line-height: 1.16;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title::after {
    width: 40px; margin-top: 13px;
  }
  body.playful-site.academic-site.home-page .hero-lead { font-size: 13px; line-height: 1.6; }
  body.playful-site.academic-site.home-page .hero-actions { margin-top: 18px; gap: 9px; }
  body.playful-site.academic-site.home-page :is(.hero-actions .button, .hero-actions .text-link, .pathway-primary) {
    font-size: 12px;
  }
  body.playful-site.academic-site.home-page :is(.v2-programs, .v2-system, .section) {
    padding: 38px 16px;
  }
  body.playful-site.academic-site.home-page :is(.v2-heading h2, .section-heading h2, .home-pathways .section-heading h2, .method h2) {
    font-size: 21px; line-height: 1.2;
  }
  body.playful-site.academic-site.home-page :is(.v2-heading, .section-heading) {
    margin-bottom: 20px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid { gap: 11px; }
  body.playful-site.academic-site.home-page .v2-program-grid > a {
    grid-template-columns: 25px minmax(0, 1fr); column-gap: 10px; padding: 15px 16px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid h3 { font-size: 17px; }
  body.playful-site.academic-site.home-page :is(.v2-programs > p, .v2-system) .text-link { font-size: 13px; }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 { font-size: 18px; }
  body.playful-site.academic-site.home-page :is(.v2-program-grid p, .section-heading > p, .home-pathways .program-card > p:not(.grade), .method-copy > p, .story-grid blockquote p, .system-summary p) {
    font-size: 13px; line-height: 1.55;
  }
  body.playful-site.academic-site.home-page :is(.grade, .pathway-details summary, .home-pathways .program-card li, .v2-programs > p, .v2-program-grid b) {
    font-size: 12px;
  }
  body.playful-site.academic-site.home-page :is(.home-pathways .program-card, .story-grid blockquote) {
    padding: 16px;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-actions { margin-top: 12px; }
  body.playful-site.academic-site.home-page .v2-five { gap: 8px; }
  body.playful-site.academic-site.home-page .v2-five > article { padding: 13px; }
  body.playful-site.academic-site.home-page .v2-five h3 { font-size: 15px; }
  body.playful-site.academic-site.home-page .v2-five :is(strong, p) { font-size: 11.5px; }
  body.playful-site.academic-site.home-page .method-copy { padding: 28px 18px; }
  body.playful-site.academic-site.home-page .story-grid {
    grid-auto-columns: minmax(264px, 82vw); margin-inline: -16px; padding-inline: 16px;
  }
  body.playful-site.academic-site.home-page .story-grid blockquote h3 { font-size: 15px; }
  body.playful-site.academic-site.home-page :is(.footer-main, .footer-bottom) { font-size: 12px; }
  body.playful-site.academic-site.home-page .site-footer { padding: 28px 16px 20px; }

  /* Extra-small homepage type scale requested for phones. */
  body.playful-site.academic-site.home-page { font-size: 12.5px; }
  body.playful-site.academic-site.home-page .announcement { font-size: 10px; }
  body.playful-site.academic-site.home-page .site-header .main-nav a { font-size: 13px; }
  body.playful-site.academic-site.home-page .hero .eyebrow { font-size: 9px; }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    max-width: 320px; font-size: 22px; line-height: 1.17;
  }
  body.playful-site.academic-site.home-page .hero-lead { font-size: 12px; line-height: 1.58; }
  body.playful-site.academic-site.home-page :is(.v2-heading h2, .section-heading h2, .home-pathways .section-heading h2, .method h2) {
    font-size: 20px;
  }
  body.playful-site.academic-site.home-page .v2-program-grid h3 { font-size: 16px; }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 { font-size: 17px; }
  body.playful-site.academic-site.home-page :is(.v2-program-grid p, .section-heading > p, .home-pathways .program-card > p:not(.grade), .method-copy > p, .story-grid blockquote p, .system-summary p) {
    font-size: 12px;
  }
  body.playful-site.academic-site.home-page :is(.grade, .pathway-details summary, .home-pathways .program-card li, .v2-programs > p, .v2-program-grid b) {
    font-size: 11px;
  }
  body.playful-site.academic-site.home-page :is(.hero-actions .button, .hero-actions .text-link, .pathway-primary) {
    font-size: 11.5px;
  }
  body.playful-site.academic-site.home-page :is(.v2-programs > p, .v2-system) .text-link { font-size: 12px; }
  body.playful-site.academic-site.home-page .v2-five h3 { font-size: 14px; }
  body.playful-site.academic-site.home-page .v2-five :is(strong, p) { font-size: 10.5px; }
  body.playful-site.academic-site.home-page .story-grid blockquote h3 { font-size: 14px; }
  body.playful-site.academic-site.home-page :is(.footer-main, .footer-bottom) { font-size: 11px; }
}

/* Tablet layout: bridge the gap between phone and desktop rules on iPad-sized screens. */
@media (min-width: 621px) and (max-width: 1100px),
  (min-width: 1101px) and (max-width: 1366px) and (hover: none) and (pointer: coarse) {
  html {
    font-size: 12px;
  }
  body.playful-site.academic-site {
    font-size: 9px;
  }
  body.playful-site.academic-site .announcement {
    min-height: 28px;
    padding-inline: 18px;
    font-size: 9px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    min-height: 62px;
    height: 62px;
    padding: 4px 16px;
    gap: 10px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    width: auto;
    height: 48px;
    max-height: 48px;
  }
  body.playful-site.academic-site .site-header .menu-toggle,
  body.playful-site.academic-site .mobile-nav-toggle {
    width: 38px;
    min-width: 38px;
    height: 38px;
    min-height: 38px;
    padding: 7px;
  }
  body.playful-site.academic-site .mobile-nav-toggle {
    display: grid;
    place-content: center;
    gap: 5px;
    margin-left: auto;
    border: 1px solid #dce5ef;
    border-radius: 6px;
    background: transparent;
    color: #182f4d;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav > .button {
    margin-left: auto;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav:has(> .button) > .mobile-nav-toggle {
    margin-left: 0;
  }
  body.playful-site.academic-site .mobile-nav-toggle span {
    display: block;
    width: 21px;
    height: 2px;
    background: currentColor;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav {
    display: none;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav.mobile-nav-open {
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    z-index: 20;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0;
    max-height: 65dvh;
    padding: 9px 20px 14px;
    overflow-y: auto;
    background: #f8fafc;
    border-bottom: 1px solid #c8d3dc;
    box-shadow: 0 14px 24px #1b344912;
  }
  body.playful-site.academic-site .simple-header.has-mobile-nav > nav.mobile-nav-open a {
    display: flex;
    align-items: center;
    min-height: 44px;
    padding: 9px 12px;
    white-space: normal;
    font-size: 10.5px;
  }
  body.playful-site.academic-site
    :is(.section, .page-wrap, .content-wrap, .competition-section, .trial, .v2-programs, .v2-system) {
    padding: 38px 16px;
  }
  body.playful-site.academic-site
    :is(.page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    padding: 26px 16px;
  }
  body.playful-site.academic-site
    :is(.page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    font-size: clamp(18px, 2.7vw, 24px);
    line-height: 1.15;
  }
  body.playful-site.academic-site.home-page .hero {
    padding: 24px 16px 28px;
    gap: 18px;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    max-width: 520px;
    margin-block: 11px 14px;
    font-size: clamp(18px, 2.45vw, 22px);
    line-height: 1.13;
  }
  body.playful-site.academic-site.home-page .hero-lead {
    font-size: 10.5px;
    line-height: 1.6;
  }
  body.playful-site.academic-site.home-page .hero-problem {
    width: min(490px, 100%);
    max-width: none;
    margin-top: 0;
  }
  body.playful-site.academic-site.home-page .problem-card {
    padding: 13px;
  }
  body.playful-site.academic-site.home-page .answer-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card {
    padding: 13px;
  }
  body.playful-site.academic-site.home-page .home-pathways .grade {
    flex-direction: column;
    align-items: flex-start;
    min-height: 36px;
    gap: 4px;
    font-size: 9px;
  }
  body.playful-site.academic-site.home-page .home-pathways .grade span {
    padding-left: 0;
    border-left: 0;
    font-size: 9px;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 {
    /* 标题随换行增长，不使用适配旧小字号的固定高度。 */
    height: auto;
    min-height: 0;
    max-height: none;
    font-size: 12px;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card > p:not(.grade) {
    height: auto;
    min-height: 0;
    max-height: none;
    font-size: 9px;
  }
  body.playful-site.academic-site.home-page .pathway-card-top {
    margin-bottom: 13px;
  }
  body.playful-site.academic-site.home-page .pathway-symbol {
    width: 31px;
    height: 31px;
  }
  body.playful-site.academic-site.home-page .pathway-actions {
    display: grid;
    grid-template-rows: auto auto;
    align-content: start;
    height: auto;
    min-height: 0;
    max-height: none;
    gap: 7px;
  }
  body.playful-site.academic-site.home-page .pathway-primary {
    padding: 7px 10px;
    font-size: 10.5px;
    white-space: nowrap;
  }
  body.playful-site.academic-site.home-page .pathway-secondary {
    align-self: start;
    min-height: 18px;
    white-space: nowrap;
  }
  body.playful-site.academic-site.home-page .story-grid blockquote {
    padding: 12px;
  }
  body.playful-site.academic-site main h2 {
    font-size: clamp(15px, 2.1vw, 18px);
  }
  body.playful-site.academic-site main h3 {
    font-size: 12px;
  }
  body.playful-site.academic-site main
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 9px;
  }
  body.playful-site.academic-site
    :is(.button, .text-link, .text-action, .pathway-primary, .pathway-secondary) {
    font-size: 9px;
  }
  body.playful-site.academic-site
    :is(.kicker, .eyebrow, .contest-tag, .problem-top, .problem-label, .problem-foot, .problem-note) {
    font-size: 8.5px;
  }
  body.playful-site.academic-site
    :is(.simple-footer, .footer-main, .footer-bottom) {
    font-size: 9px;
  }
  body.playful-site.academic-site
    :is(.program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .system-panel, .trial-form, .inquiry-form) {
    padding: 16px;
  }
  body.playful-site.academic-site .club-hero {
    width: calc(100% - 64px);
    padding-block: 38px;
    gap: 28px;
  }
  body.playful-site.academic-site.home-page .footer-main {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, .9fr) minmax(0, 1.6fr);
    gap: 32px;
  }
  body.playful-site.academic-site.home-page .footer-main a[href="algebra.html"] {
    white-space: nowrap;
  }
  body.playful-site.academic-site .program-overview > p {
    margin: 14px 0 0;
  }
  body.playful-site.academic-site .program-overview > p .text-action {
    display: block;
    width: 100%;
    min-height: 48px;
    padding: 12px 14px;
    border: 1px solid #bccbd5;
    border-left: 3px solid #405d72;
    background: #f5f8fc;
    color: #305f86;
    line-height: 1.45;
    text-decoration: none;
  }
  body.playful-site.academic-site
    :is(input:not([type=checkbox]):not([type=radio]):not([type=hidden]), select, textarea) {
    font-size: 16px;
  }
}

@media (min-width: 900px) and (max-width: 1100px),
  (min-width: 1101px) and (max-width: 1366px) and (hover: none) and (pointer: coarse) {
  body.playful-site.academic-site.home-page .hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(285px, .82fr);
    align-items: center;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (min-width: 621px) and (max-width: 900px) {
  body.playful-site.academic-site.algebra-page .algebra-menu {
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 40px;
    padding: 7px 10px;
    margin-left: auto;
    border: 1px solid #c7c8bd;
    background: transparent;
    color: #182f4d;
    font-size: 11px;
  }
  body.playful-site.academic-site.algebra-page .algebra-header > nav {
    display: none;
  }
  body.playful-site.academic-site.algebra-page .algebra-header > nav.is-open {
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    z-index: 20;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px 22px 16px;
    background: #f8f7f3;
    border-bottom: 1px solid #d9d6cc;
    box-shadow: 0 12px 24px #1b344911;
  }
  body.playful-site.academic-site.algebra-page .algebra-header > nav.is-open a {
    min-height: 42px;
    padding: 10px 0;
    font-size: 11px;
  }
}

@media (min-width: 621px) and (max-width: 899px) {
  body.playful-site.academic-site.home-page .hero {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }
  body.playful-site.academic-site.home-page .hero-problem {
    display: block;
    width: min(560px, 100%);
    justify-self: center;
  }
  body.playful-site.academic-site.home-page .problem-card {
    padding: 18px;
  }
  body.playful-site.academic-site.home-page .answer-row {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 8px;
  }
  body.playful-site.academic-site.home-page .problem-note {
    right: 0;
  }
}

/* Fluid phone sizing: interpolate spacing across small and large phones. */
@media (max-width: 620px) {
  body.playful-site.academic-site {
    --phone-gutter: clamp(14px, 4.4vw, 20px);
    --phone-section-space: clamp(34px, 9vw, 44px);
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    padding-right: var(--phone-gutter);
    padding-left: var(--phone-gutter);
  }
  body.playful-site.academic-site
    :is(.hero, .page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    padding-right: var(--phone-gutter);
    padding-left: var(--phone-gutter);
  }
  body.playful-site.academic-site
    :is(.section, .page-wrap, .content-wrap, .competition-section, .trial, .v2-programs, .v2-system) {
    padding-right: var(--phone-gutter);
    padding-left: var(--phone-gutter);
  }
  body.playful-site.academic-site.home-page :is(.v2-programs, .v2-system, .section) {
    padding-top: var(--phone-section-space);
    padding-bottom: var(--phone-section-space);
  }
  body.playful-site.academic-site
    :is(.program-card, .home-pathways .program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .trial-form, .inquiry-form) {
    padding-right: clamp(16px, 4.8vw, 22px);
    padding-left: clamp(16px, 4.8vw, 22px);
  }
  body.playful-site.academic-site.home-page .hero {
    padding-top: clamp(26px, 7.5vw, 34px);
    padding-bottom: clamp(30px, 8.5vw, 40px);
  }
  body.playful-site.academic-site.home-page .hero-actions > a,
  body.playful-site.academic-site .inquiry-form :is(button, .button) {
    max-width: 100%;
  }
  body.playful-site.academic-site :is(img, svg, video, canvas) {
    max-width: 100%;
  }
  body.playful-site.academic-site:not(.home-page) {
    font-size: 13px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.hero .home-hero-title, .page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    font-size: clamp(21px, 6.8vw, 24px);
  }
  body.playful-site.academic-site.algebra-course-page .course-hero h1,
  body.playful-site.academic-site .club-hero h1 {
    font-size: clamp(21px, 6.8vw, 24px);
  }
  body.playful-site.academic-site:not(.home-page) main h2 {
    font-size: clamp(18px, 5.5vw, 20px);
  }
  body.playful-site.academic-site:not(.home-page) main h3 {
    font-size: 15px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 12px;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(19px, 5.8vw, 22px);
  }
  body.playful-site.academic-site.home-page
    :is(.v2-heading h2, .section-heading h2, .home-pathways .section-heading h2, .method h2) {
    font-size: clamp(17px, 5.2vw, 19px);
  }
  body.playful-site.academic-site.home-page
    :is(.v2-program-grid h3, .home-pathways .program-card h3) {
    font-size: clamp(14px, 4.5vw, 16px);
  }
  body.playful-site.academic-site.home-page .hero-lead {
    font-size: 11.5px;
  }
  body.playful-site.academic-site.home-page
    :is(.v2-program-grid p, .section-heading > p, .home-pathways .program-card > p:not(.grade), .method-copy > p, .story-grid blockquote p, .system-summary p) {
    font-size: 11.5px;
  }
  body.playful-site.academic-site.home-page
    :is(.grade, .pathway-details summary, .home-pathways .program-card li, .v2-programs > p, .v2-program-grid b) {
    font-size: 10.5px;
  }
  body.playful-site.academic-site
    :is(input:not([type=checkbox]):not([type=radio]):not([type=hidden]), select, textarea) {
    font-size: 16px;
  }
}

/* Compact phone landscape without affecting portrait typography. */
@media (min-width: 480px) and (max-width: 759px) and (max-height: 500px) and (orientation: landscape) {
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    min-height: 68px;
    height: 68px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    height: 52px;
    max-height: 52px;
  }
  body.playful-site.academic-site.home-page .announcement {
    min-height: 28px;
    height: 28px;
  }
  body.playful-site.academic-site.home-page .hero {
    padding-top: 24px;
    padding-bottom: 28px;
  }
}


/* ===== 原模块：design-refinement.css ===== */
/* 跨页面排版、间距与组件细节覆盖。修改时保留页面中样式表的加载顺序。 */
/* Preserve the palette while distinguishing primary paths from supporting content. */
body.playful-site.academic-site :is(.v2-five > article, .topic-matrix > article, .account-stats article, .overview article, .study-paper, .worked-example, .unit-detail, .panel, .catalog-filters, .placement-help, .preview-note, .common-mistake, .next-review, .story-grid blockquote),
body.playful-site.academic-site :is(.v2-five > article, .topic-matrix > article, .account-stats article, .overview article, .study-paper, .worked-example, .unit-detail, .panel, .catalog-filters, .placement-help, .preview-note, .common-mistake, .next-review, .story-grid blockquote):hover {
  box-shadow: inset 0 1px 0 #ffffff70, 0 2px 6px #182f4d0d;
  transform: none;
}
body.playful-site.academic-site .pathway-details { margin: 8px 0 18px; }
body.playful-site.academic-site .pathway-details summary { cursor: pointer; padding-block: 12px; min-height: 44px; font-size: 15px; font-weight: 600; }
body.playful-site.academic-site .home-pathways .pathway-details ul { margin: 8px 0 0; padding-top: 12px; }
body.playful-site.academic-site .home-pathways .pathway-actions { min-height: 104px; }
body.playful-site.academic-site .v2-five { gap: 12px; }
body.playful-site.academic-site .v2-five > article { padding: 22px; }
body.playful-site.academic-site .brand picture { display: block; }
@media (min-width: 1001px) {
  body.playful-site.academic-site .home-pathways .program-card > p:not(.grade) { min-height: 5.1em; }
}
@media (max-width: 620px) {
  body.playful-site.academic-site :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) picture .brand-logo {
    width: clamp(120px, calc(100vw - 200px), 160px); height: auto; max-height: none;
  }
  body.playful-site.academic-site .simple-header > .button { font-size: 13px; padding-inline: 8px; }
  body.playful-site.academic-site .home-pathways .pathway-actions { min-height: 0; }
  body.playful-site.academic-site .v2-five > article { padding: 18px 20px; }
}
@media print {
  body.playful-site.academic-site .pathway-details::details-content { content-visibility: visible; }
}


/* ===== 原模块：finishing.css ===== */
/* 页面视觉细节覆盖；需遵循 HTML 中既有加载顺序。修改时保留页面中样式表的加载顺序。 */
body.playful-site.academic-site .course-map { min-width: 0; align-self: start; }
html { font-size: 15px; }
body.playful-site.academic-site { font-size: 15px; }
body.playful-site.academic-site .test-preparation-cards > article > .button {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 50px;
  min-height: 50px;
  max-height: 50px;
  padding: 8px 10px;
  font-size: 13px;
  line-height: 1.2;
  text-align: center;
  white-space: nowrap;
}
@media (min-width: 621px) and (max-width: 1100px),
  (min-width: 1101px) and (max-width: 1366px) and (hover: none) and (pointer: coarse) {
  html {
    font-size: 12px;
  }
  body.playful-site.academic-site .test-preparation-cards > article > .button {
    height: 42px;
    min-height: 42px;
    max-height: 42px;
    font-size: 10px;
    letter-spacing: -.01em;
  }
  body.playful-site.academic-site.algebra-page .course-pair {
    align-items: stretch;
  }
  body.playful-site.academic-site.algebra-page .course-pair > .course-card {
    display: flex;
    flex-direction: column;
    height: 100%;
  }
  body.playful-site.academic-site.algebra-page .course-pair > .course-card > .a-button {
    width: 100%;
    min-height: 48px;
    margin-top: auto;
  }
  body.playful-site.academic-site .system-panel[aria-labelledby="algebra-assessments-title"] .hero-actions {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 160px));
    align-items: stretch;
    gap: 14px;
  }
  body.playful-site.academic-site .system-panel[aria-labelledby="algebra-assessments-title"] .hero-actions .button {
    width: 100%;
    min-height: 46px;
    padding-inline: 10px;
  }
}
@media (max-width: 620px) {
  body.playful-site.academic-site .test-preparation-cards > article > .button {
    height: 46px;
    min-height: 46px;
    max-height: 46px;
    font-size: 12px;
  }
}

/* Keep the focused Algebra pathway visually attached to Explore Programs. */
body.playful-site.academic-site.home-page .algebra-program-link {
  margin: 16px 0 0;
}
body.playful-site.academic-site.home-page .algebra-program-link .text-link {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 18px;
  width: 100%;
  min-height: 66px;
  padding: 13px 18px;
  border: 1px solid #bccbd5;
  border-left: 3px solid #405d72;
  border-radius: 3px;
  background: #f5f8fc;
  text-decoration: none;
}
body.playful-site.academic-site.home-page .algebra-program-link span {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}
body.playful-site.academic-site.home-page .algebra-program-link strong {
  font-size: 14px;
  line-height: 1.35;
}
body.playful-site.academic-site.home-page .algebra-program-link small {
  color: #586b7c;
  font-size: 12px;
  line-height: 1.45;
}
body.playful-site.academic-site.home-page .algebra-program-link b {
  color: #305f86;
  font-size: 13px;
  white-space: nowrap;
}
@media (max-width: 620px) {
  body.playful-site.academic-site.home-page .algebra-program-link .text-link {
    grid-template-columns: minmax(0, 1fr);
    gap: 9px;
    padding: 13px 15px;
  }
}
body.playful-site.academic-site
  :is(.hero-lead, .hero-description, .page-hero > p:not(.kicker), .content-hero > p:not(.kicker), .section-heading > p) {
  font-size: 16px;
}
body.playful-site.academic-site
  :is(.program-card > p:not(.grade), .program-card li, .info-card p, .info-card li, .content-grid p, .content-grid li) {
  font-size: 14px;
}
@media (min-width: 1367px),
  (min-width: 1101px) and (max-width: 1366px) and (hover: hover) and (pointer: fine) {
  body.playful-site.academic-site
    :is(.hero h1, .page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    font-size: clamp(38px, 3.7vw, 54px);
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(36px, 3vw, 44px);
  }
  body.playful-site.academic-site main h2 {
    font-size: clamp(25px, 2.4vw, 34px);
  }
  body.playful-site.academic-site :is(.program-card h3, .info-card h3, .content-grid h3) {
    font-size: 20px;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card h3 {
    font-size: 23px;
  }
}
body.playful-site.academic-site .course-map > summary {
  cursor: pointer; min-height: 48px; padding: 14px 18px; margin-bottom: 14px;
  border: 1px solid currentColor; border-radius: 6px; font-size: 15px; font-weight: 600;
}

/* Keep the three homepage learning-system cards and their calls to action aligned. */
body.playful-site.academic-site.home-page .story-grid blockquote {
  display: flex;
  flex-direction: column;
  height: 100%;
}
body.playful-site.academic-site.home-page .story-grid blockquote > p {
  flex: 1 1 auto;
}
body.playful-site.academic-site.home-page .story-grid blockquote > footer {
  margin-top: auto;
}

/* Prevent the MH badge from being squeezed or pushed outside the problem card. */
body.playful-site.academic-site.home-page .problem-foot {
  min-width: 0;
  gap: 12px;
}
body.playful-site.academic-site.home-page .problem-foot > span {
  flex: 1 1 auto;
  min-width: 0;
  overflow-wrap: anywhere;
}
body.playful-site.academic-site.home-page .problem-foot > strong {
  display: grid;
  flex: 0 0 32px;
  place-items: center;
  width: 32px;
  height: 32px;
  min-width: 32px;
  min-height: 32px;
  padding: 0;
  overflow: hidden;
  border-radius: 50%;
  font-size: 11px;
  line-height: 1;
  white-space: nowrap;
}

/* Keep every Explore program button on the same baseline on desktop. */
@media (min-width: 1001px) {
  body.playful-site.academic-site.home-page .home-pathways .program-card {
    height: 100%;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    margin-top: auto;
  }
}
body.playful-site.academic-site .system-summary { margin-top: 36px; padding: 24px 0; border-top: 1px solid #bccbd5; }
body.playful-site.academic-site .system-summary p { margin: 8px 0; font-size: 16px; line-height: 1.7; }
body.playful-site.academic-site .system-summary a { display: inline-flex; align-items: center; min-height: 44px; text-decoration: underline; text-underline-offset: 4px; font-weight: 600; }
body.playful-site.academic-site .inquiry-form fieldset {
  grid-column: 1/-1; min-width: 0; margin: 22px 0 0; padding: 20px 0 0;
  border: 0; border-top: 1px solid #c8d3dc;
}
body.playful-site.academic-site .inquiry-form legend { padding: 0 12px 0 0; font-size: 20px; font-weight: 700; }
body.playful-site.academic-site .inquiry-fields { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 0 18px; }
body.playful-site.academic-site .inquiry-fields label { min-width: 0; }
body.playful-site.academic-site .inquiry-optional { grid-column: 1/-1; margin-top: 24px; border-block: 1px solid #c8d3dc; padding-block: 8px; }
body.playful-site.academic-site .inquiry-optional summary { cursor: pointer; min-height: 44px; padding-block: 12px; font-weight: 600; }
body.playful-site.academic-site .inquiry-contact { display: inline-flex; align-items: center; min-height: 44px; gap: 8px; font-weight: 700; }
body.playful-site.academic-site .inquiry-form .required-note { font-size: 14px; }
body.playful-site.academic-site #inquiry-context { padding: 12px 14px; border-left: 3px solid #405d72; background: #edf3f7; font-size: 16px; }
body.playful-site.academic-site .inquiry-unavailable { padding: 16px; background: #fff5e9; border: 1px solid #d5a58e; border-radius: 6px; line-height: 1.6; }
body.playful-site.academic-site .inquiry-unavailable a { display: inline-flex; min-height: 44px; align-items: center; font-weight: 700; }
@media (max-width: 620px) {
  body.playful-site.academic-site .inquiry-fields { grid-template-columns: minmax(0,1fr); }
  body.playful-site.academic-site .system-summary { margin-top: 24px; padding-block: 20px; }
  body.playful-site.academic-site .inquiry-process { margin: 0; }
  body.playful-site.academic-site .inquiry-process summary { min-height: 44px; padding-block: 12px; cursor: pointer; font-weight: 600; }
}

/* Unified phone scale for all inner pages. The homepage has its own compact composition. */
@media (max-width: 620px) {
  body.playful-site.academic-site:not(.home-page) {
    font-size: 14px;
    line-height: 1.55;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    width: 100%; height: auto; min-height: 68px; padding: 9px 16px; gap: 10px;
  }
  body.playful-site.academic-site:not(.home-page) .simple-header.has-mobile-nav { flex-wrap: wrap; }
  body.playful-site.academic-site:not(.home-page)
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) picture .brand-logo {
    width: 124px; height: auto; max-height: 48px;
  }
  body.playful-site.academic-site:not(.home-page) .simple-header > .button {
    min-height: 40px; padding: 8px 10px; font-size: 12px;
  }
  body.playful-site.academic-site:not(.home-page) .mobile-nav-toggle {
    width: 40px; height: 40px; min-width: 40px; min-height: 40px; padding: 8px;
  }
  body.playful-site.academic-site:not(.home-page) .simple-header.has-mobile-nav > nav a,
  body.playful-site.academic-site:not(.home-page) .site-header .main-nav a {
    min-height: 42px; padding-block: 9px; font-size: 13px;
  }
  body.playful-site.academic-site:not(.home-page) .club-login,
  body.playful-site.academic-site:not(.home-page) .club-header > .club-button { display: none; }
  body.playful-site.academic-site:not(.home-page) .club-header { flex-wrap: nowrap; }
  body.playful-site.academic-site:not(.home-page) .club-menu {
    margin-left: auto; min-height: 40px; padding: 8px 10px; font-size: 12px;
  }
  body.playful-site.academic-site:not(.home-page) .course-header nav { gap: 10px; font-size: 12px; }
  body.playful-site.academic-site:not(.home-page) .support-link span { margin-left: 5px; }

  body.playful-site.academic-site:not(.home-page)
    :is(.hero, .page-hero, .content-hero, .competition-hero, .science-hero, .school-hero, .algebra-hero, .course-hero) {
    padding: 30px 16px; gap: 22px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.hero h1, .page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1) {
    margin-block: 10px 16px; font-size: 26px; line-height: 1.18; letter-spacing: -.025em;
  }
  body.playful-site.academic-site:not(.home-page) .course-hero h1 {
    margin-block: 8px 12px; font-size: 32px; line-height: 1.12; letter-spacing: -.03em;
  }
  body.playful-site.academic-site:not(.home-page) .club-hero {
    width: calc(100% - 32px); padding-block: 34px; gap: 26px;
  }
  body.playful-site.academic-site:not(.home-page) .club-hero h1 {
    margin-bottom: 18px; font-size: 29px; line-height: 1.14;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.hero-lead, .hero-description, .club-lead, .competition-hero > div > p:not(.kicker), .content-hero > p:not(.kicker), .page-hero > p:not(.kicker)) {
    font-size: 14px; line-height: 1.6;
  }
  body.playful-site.academic-site:not(.home-page) :is(.eyebrow, .kicker, .club-kicker, .contest-tag, .study-label) {
    font-size: 10.5px; line-height: 1.5; letter-spacing: .08em;
  }

  body.playful-site.academic-site:not(.home-page)
    :is(.section, .page-wrap, .content-wrap, .competition-section, .a-section, .club-section, .club-intro, .club-bridge, .club-closing, .trial) {
    padding-block: 38px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.section, .page-wrap, .content-wrap, .competition-section, .trial) {
    padding-inline: 16px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.page-intro h2, .section-heading h2, .contest-heading h2, .program-copy h2, .content-grid h2, .club-section h2, .club-intro h2, .club-bridge h2, .section-intro h2, .course-fit h2) {
    font-size: 22px; line-height: 1.22; letter-spacing: -.02em;
  }
  body.playful-site.academic-site:not(.home-page) main h3 { font-size: 17px; line-height: 1.3; }
  body.playful-site.academic-site:not(.home-page) main
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 14px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.program-card, .home-pathways .program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .club-duo article, .assessment-card, .sample-card, .unit-detail, .trial-form, .inquiry-form) {
    padding: 18px;
  }
  body.playful-site.academic-site:not(.home-page)
    :is(.program-grid, .info-grid, .content-grid, .pathway-cards, .stage-grid, .contest-grid, .club-duo) {
    gap: 14px;
  }
  body.playful-site.academic-site:not(.home-page) :is(.course-container, .club-wrap, .a-container) {
    width: calc(100% - 32px);
  }
  body.playful-site.academic-site:not(.home-page) .course-path,
  body.playful-site.academic-site:not(.home-page) :is(.breadcrumb, .course-switch > p, .course-switch small) {
    font-size: 12px;
  }
  body.playful-site.academic-site:not(.home-page) .course-switch a {
    min-height: 44px; padding: 11px; font-size: 13px;
  }
  body.playful-site.academic-site:not(.home-page) .explorer-tabs button { font-size: 12px; }
  body.playful-site.academic-site:not(.home-page) .club-notebook { padding: 18px; }
  body.playful-site.academic-site:not(.home-page) .club-question { padding-block: 14px; font-size: 20px; }
  body.playful-site.academic-site:not(.home-page) .club-copy ul { columns: 1; }
  body.playful-site.academic-site:not(.home-page) .club-subnav { padding: 14px 16px; gap: 8px 16px; font-size: 11px; }
  body.playful-site.academic-site:not(.home-page) .contest-table { min-width: 520px; font-size: 12px; }
  body.playful-site.academic-site:not(.home-page) .contest-table :is(th, td) { padding: 12px 14px; }
  body.playful-site.academic-site:not(.home-page) .algebra-announcement {
    padding: 7px 12px; font-size: 11px; letter-spacing: .08em;
  }
  body.playful-site.academic-site:not(.home-page) .system-flow {
    grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; margin-block: 24px;
  }
  body.playful-site.academic-site:not(.home-page) .system-flow > div {
    min-height: 78px; padding: 14px 10px; border: 1px solid #d5d1c8;
  }
  body.playful-site.academic-site:not(.home-page) .system-flow > div:last-child { grid-column: 1 / -1; }
  body.playful-site.academic-site:not(.home-page) .content-grid h2 { margin-bottom: 14px; }
  body.playful-site.academic-site:not(.home-page) :is(.report-panel, .system-panel) {
    margin-top: 32px; padding: 20px;
  }
  body.playful-site.academic-site:not(.home-page) .inquiry-card-head h2 { font-size: 22px; }
  body.playful-site.academic-site:not(.home-page) .inquiry-card-head { padding-bottom: 20px; }
  body.playful-site.academic-site:not(.home-page) .inquiry-section-heading { margin-block: 24px 16px; }
  body.playful-site.academic-site:not(.home-page) .inquiry-fields label { font-size: 13px; }
  body.playful-site.academic-site:not(.home-page) .inquiry-form legend { font-size: 18px; }
  body.playful-site.academic-site:not(.home-page) :is(.button, .club-button, .a-button, .pathway-primary) {
    min-height: 44px; font-size: 12px;
  }
  body.playful-site.academic-site:not(.home-page) :is(input:not([type=checkbox]):not([type=radio]):not([type=hidden]), select, textarea) {
    font-size: 16px;
  }
  body.playful-site.academic-site:not(.home-page) :is(.simple-footer, .site-footer, .club-footer, .course-footer) {
    padding: 26px 16px; font-size: 12px;
  }
}


/* ===== 原模块：ipad-redesign.css ===== */
/* 平板尺寸下的页面布局修正。修改时保留页面中样式表的加载顺序。 */
/* iPad-only layout, rebuilt as a coherent tablet system.
   Phone and desktop styling are intentionally outside these queries. */
@media (min-width: 744px) and (max-width: 1400px) {
  html {
    font-size: 14px;
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
  }
  body.playful-site.academic-site {
    --tablet-gutter: clamp(32px, 4.5vw, 58px);
    --tablet-space: clamp(38px, 5vw, 56px);
    font-size: 13px;
    line-height: 1.58;
  }

  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    width: 100%;
    height: 68px;
    min-height: 68px;
    padding: 6px var(--tablet-gutter);
    gap: 14px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    width: auto;
    height: 52px;
    max-height: 52px;
  }
  body.playful-site.academic-site :is(.mobile-nav-toggle, .site-header .menu-toggle) {
    display: grid;
    width: 42px;
    min-width: 42px;
    height: 42px;
    min-height: 42px;
    padding: 9px;
  }

  body.playful-site.academic-site
    :is(.section, .page-wrap, .content-wrap, .competition-section, .trial, .v2-programs, .v2-system) {
    padding: var(--tablet-space) var(--tablet-gutter);
  }
  body.playful-site.academic-site :is(.a-container, .course-container, .club-wrap) {
    width: calc(100% - (2 * var(--tablet-gutter)));
  }
  body.playful-site.academic-site
    :is(.a-section, .club-section, .club-intro, .club-bridge, .club-closing) {
    padding-block: var(--tablet-space);
  }
  body.playful-site.academic-site
    :is(.page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    min-height: 0;
    padding: 38px var(--tablet-gutter);
  }

  body.playful-site.academic-site
    :is(.page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    margin-block: 8px 14px;
    font-size: clamp(28px, 3vw, 36px);
    line-height: 1.14;
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(28px, 3.1vw, 38px);
    line-height: 1.16;
  }
  body.playful-site.academic-site main h2 { font-size: clamp(21px, 2.35vw, 28px); }
  body.playful-site.academic-site main h3 { font-size: 16px; }
  body.playful-site.academic-site main
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 13px;
  }
  body.playful-site.academic-site
    :is(.kicker, .eyebrow, .club-kicker, .contest-tag, .study-label, .problem-top, .problem-label, .problem-foot) {
    font-size: 10.5px;
  }
  body.playful-site.academic-site
    :is(.button, .a-button, .club-button, .text-link, .text-action, .pathway-primary, .pathway-secondary) {
    min-height: 42px;
    padding: 9px 13px;
    font-size: 12px;
  }

  body.playful-site.academic-site
    :is(.program-grid, .info-grid, .content-grid, .pathway-cards, .stage-grid, .contest-grid, .club-duo) {
    gap: 16px;
  }
  body.playful-site.academic-site
    :is(.program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .club-duo article, .assessment-card, .sample-card, .unit-detail, .system-panel, .trial-form, .inquiry-form) {
    min-width: 0;
    padding: 20px;
  }
  body.playful-site.academic-site :is(.content-grid, .info-grid, .stage-grid) {
    align-items: stretch;
  }
  body.playful-site.academic-site :is(.content-grid, .stage-grid) > article {
    display: flex;
    flex-direction: column;
    height: 100%;
  }
  body.playful-site.academic-site :is(.content-grid, .stage-grid) > article > :is(.button, a:last-child) {
    margin-top: auto;
  }
  body.playful-site.academic-site .content-grid.subject-pair {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  body.playful-site.academic-site .test-preparation-cards > article {
    display: flex;
    flex-direction: column;
    height: 100%;
  }
  body.playful-site.academic-site .test-preparation-cards > article > .button {
    width: 100%;
    height: 42px;
    min-height: 42px;
    max-height: 42px;
    margin-top: auto;
    font-size: 12px;
  }

  body.playful-site.academic-site .system-flow {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 0;
  }
  body.playful-site.academic-site .system-flow > div {
    min-height: 82px;
    padding: 12px 8px;
  }
  body.playful-site.academic-site .system-flow > div:last-child { grid-column: auto; }
  body.playful-site.academic-site .inquiry-form { max-width: 960px; }
  body.playful-site.academic-site
    :is(input:not([type=checkbox]):not([type=radio]):not([type=hidden]), select, textarea) {
    font-size: 16px;
  }

  body.playful-site.academic-site .simple-footer,
  body.playful-site.academic-site :is(.site-footer, .club-footer, .course-footer) {
    padding: 24px var(--tablet-gutter);
    font-size: 12px;
  }
}

/* Portrait: vertical reading flow with horizontal summary cards. */
@media (min-width: 744px) and (max-width: 1040px) and (orientation: portrait) {
  body.playful-site.academic-site {
    --tablet-gutter: clamp(30px, 4.2vw, 38px);
    --tablet-space: 44px;
    font-size: 13.5px;
  }
  body.playful-site.academic-site.home-page .hero {
    grid-template-columns: minmax(0, 1fr);
    gap: 30px;
    padding: 42px var(--tablet-gutter) 48px;
  }
  body.playful-site.academic-site.home-page .hero-copy { max-width: 620px; }
  body.playful-site.academic-site.home-page .hero-problem {
    width: min(540px, 100%);
    justify-self: center;
  }
  body.playful-site.academic-site.home-page .problem-card { padding: 22px; }

  body.playful-site.academic-site :is(.competition-hero, .course-hero-grid, .club-hero) {
    grid-template-columns: minmax(0, 1fr);
  }
  body.playful-site.academic-site .competition-hero,
  body.playful-site.academic-site .club-hero { gap: 30px; }
  body.playful-site.academic-site .club-hero {
    width: calc(100% - (2 * var(--tablet-gutter)));
    padding-block: 40px;
  }
  body.playful-site.academic-site .club-notebook { padding: 20px; }
  body.playful-site.academic-site .club-question { padding-block: 11px; font-size: 18px; }

  body.playful-site.academic-site :is(.content-grid, .info-grid, .stage-grid) {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  body.playful-site.academic-site
    :is(.content-grid, .info-grid, .stage-grid) > :last-child:nth-child(odd) {
    grid-column: 1 / -1;
  }

  body.playful-site.academic-site .test-preparation-cards {
    grid-template-columns: minmax(0, 1fr);
    grid-auto-rows: 1fr;
    gap: 14px;
  }
  body.playful-site.academic-site .test-preparation-cards > article,
  body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    display: grid;
    grid-column: auto;
    grid-template-columns: 88px minmax(0, 1fr) 164px;
    grid-template-rows: auto auto;
    align-items: center;
    gap: 10px 18px;
    min-height: 230px;
    height: 100%;
    padding: 20px;
  }
  body.playful-site.academic-site .test-preparation-cards > article > h2 {
    grid-column: 1;
    grid-row: 1 / 3;
    min-height: 0;
    margin: 0;
    padding-right: 18px;
    border-right: 1px solid #c8d3dc;
  }
  body.playful-site.academic-site .test-preparation-cards > article > p {
    grid-column: 2;
    grid-row: 1;
    margin: 0;
  }
  body.playful-site.academic-site .test-preparation-cards > article > ul {
    grid-column: 2;
    grid-row: 2;
    margin: 0;
    padding-left: 18px;
  }
  body.playful-site.academic-site .test-preparation-cards > article > .button {
    grid-column: 3;
    grid-row: 1 / 3;
    align-self: center;
    margin: 0;
  }

  body.playful-site.academic-site.home-page .home-pathways .program-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card {
    display: grid;
    grid-template-columns: 72px minmax(0, 1fr) 176px;
    grid-template-rows: auto auto auto auto;
    gap: 7px 18px;
    min-height: 190px;
    height: 100%;
    padding: 20px;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-card-top {
    grid-column: 1;
    grid-row: 1 / 5;
    align-self: start;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card > .grade {
    grid-column: 2;
    grid-row: 1;
    min-height: 0;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card > h3 {
    grid-column: 2;
    grid-row: 2;
    width: auto;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card > p:not(.grade) {
    grid-column: 2;
    grid-row: 3;
    width: auto;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-details {
    grid-column: 2;
    grid-row: 4;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    grid-column: 3;
    grid-row: 1 / 5;
    align-self: center;
    width: 100%;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-primary,
  body.playful-site.academic-site.home-page .home-pathways .pathway-secondary {
    width: 100%;
  }

  body.playful-site.academic-site.home-page .footer-main {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr);
    gap: 30px 46px;
  }
  body.playful-site.academic-site.home-page .footer-main > div:first-child {
    grid-column: 1 / -1;
  }
  body.playful-site.academic-site.home-page .footer-main > div:nth-child(2) a {
    white-space: nowrap;
  }

  body.playful-site.academic-site .unit-layout {
    grid-template-columns: 210px minmax(0, 1fr);
    gap: 24px;
  }
  body.playful-site.academic-site .practice-layout { grid-template-columns: minmax(0, 1fr); }
  body.playful-site.academic-site .review-sidebar { order: -1; }
}

/* Landscape: full-width reading canvas with intentional two- and three-column groups. */
@media (min-width: 900px) and (max-width: 1400px) and (orientation: landscape) {
  html { font-size: 12.5px; }
  body.playful-site.academic-site {
    --tablet-gutter: clamp(44px, 5vw, 68px);
    --tablet-space: clamp(32px, 3.8vw, 44px);
    font-size: 11.5px;
    line-height: 1.54;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    height: 60px;
    min-height: 60px;
    padding-block: 5px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    height: 46px;
    max-height: 46px;
  }
  body.playful-site.academic-site :is(.mobile-nav-toggle, .site-header .menu-toggle) {
    width: 38px;
    min-width: 38px;
    height: 38px;
    min-height: 38px;
    padding: 8px;
  }
  body.playful-site.academic-site
    :is(.page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    padding-block: 30px;
  }
  body.playful-site.academic-site
    :is(.page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    margin-block: 7px 11px;
    font-size: clamp(23px, 2.5vw, 30px);
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(23px, 2.55vw, 31px);
  }
  body.playful-site.academic-site main h2 { font-size: clamp(18px, 2vw, 23px); }
  body.playful-site.academic-site main h3 { font-size: 14px; }
  body.playful-site.academic-site main
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 11.5px;
  }
  body.playful-site.academic-site
    :is(.kicker, .eyebrow, .club-kicker, .contest-tag, .study-label, .problem-top, .problem-label, .problem-foot) {
    font-size: 9.5px;
  }
  body.playful-site.academic-site
    :is(.button, .a-button, .club-button, .text-link, .text-action, .pathway-primary, .pathway-secondary) {
    min-height: 38px;
    padding: 8px 11px;
    font-size: 10.5px;
  }
  body.playful-site.academic-site
    :is(.program-grid, .info-grid, .content-grid, .pathway-cards, .stage-grid, .contest-grid, .club-duo) {
    gap: 14px;
  }
  body.playful-site.academic-site
    :is(.program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .club-duo article, .assessment-card, .sample-card, .unit-detail, .system-panel, .trial-form, .inquiry-form) {
    padding: 16px;
  }
  body.playful-site.academic-site.home-page .hero {
    grid-template-columns: minmax(0, 1.08fr) minmax(370px, .92fr);
    align-items: center;
    gap: clamp(30px, 3.6vw, 48px);
    min-height: 0;
    padding: 34px var(--tablet-gutter) 38px;
  }
  body.playful-site.academic-site.home-page .hero-problem { width: min(420px, 100%); }
  body.playful-site.academic-site.home-page .problem-card { padding: 16px; }

  body.playful-site.academic-site :is(.content-grid, .info-grid, .stage-grid) {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  body.playful-site.academic-site.home-page .home-pathways .program-grid,
  body.playful-site.academic-site .test-preparation-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: stretch;
  }
  body.playful-site.academic-site.home-page .home-pathways .program-card {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 16px;
  }
  body.playful-site.academic-site.home-page .home-pathways .pathway-actions { margin-top: auto; }

  body.playful-site.academic-site .club-hero {
    width: calc(100% - (2 * var(--tablet-gutter)));
    grid-template-columns: minmax(0, 1.08fr) minmax(340px, .92fr);
    gap: 32px;
    padding-block: 34px;
  }
  body.playful-site.academic-site .club-notebook { padding: 16px; }
  body.playful-site.academic-site .club-question { padding-block: 9px; font-size: 16px; }
  body.playful-site.academic-site .club-editorial {
    grid-template-columns: minmax(260px, .78fr) minmax(0, 1.22fr);
    gap: clamp(34px, 4.5vw, 60px);
  }

  body.playful-site.academic-site .competition-hero {
    grid-template-columns: minmax(0, 1.18fr) minmax(350px, .82fr);
    gap: 36px;
  }
  body.playful-site.academic-site .course-hero { padding-block: 24px 28px; }
  body.playful-site.academic-site .course-hero-grid {
    grid-template-columns: minmax(0, 1fr) minmax(280px, 310px);
    gap: 32px;
  }
  body.playful-site.academic-site .breadcrumb { margin-bottom: 24px; }
  body.playful-site.academic-site .unit-layout {
    grid-template-columns: 240px minmax(0, 1fr);
    gap: 26px;
  }
  body.playful-site.academic-site .explorer-tabs { margin-bottom: 24px; }

  body.playful-site.academic-site.home-page .footer-main {
    grid-template-columns: minmax(230px, .8fr) minmax(260px, .72fr) minmax(380px, 1.2fr);
    gap: 34px;
  }
  body.playful-site.academic-site.home-page .footer-main > div:nth-child(2) a,
  body.playful-site.academic-site.home-page .footer-main > div:nth-child(3) a {
    white-space: nowrap;
  }
  body.playful-site.academic-site .simple-footer,
  body.playful-site.academic-site :is(.site-footer, .club-footer, .course-footer) {
    padding-block: 20px;
    font-size: 11px;
  }
}

@media (min-width: 1251px) and (max-width: 1400px) and (orientation: landscape) {
  body.playful-site.academic-site :is(.mobile-nav-toggle, .site-header .menu-toggle) {
    display: none;
  }
}

/* Real iPad portrait viewports can be reported as 1032px wide. Keep the
   stage marker in its own rail so it can never collide with grade metadata. */
@media (min-width: 744px) and (max-width: 1400px) {
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .section-heading {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card {
    grid-template-columns: 90px minmax(0, 1fr) minmax(128px, 154px);
    min-height: 200px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-card-top {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: flex-start;
    gap: 10px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-step {
    white-space: nowrap;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article,
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    grid-template-columns: 78px minmax(0, 1fr) minmax(124px, 146px);
  }
}

/* Keep every dark-blue action inside its parent card while Safari recalculates
   text metrics after an iPad rotation. */
@media (min-width: 700px) and (max-width: 1400px) {
  body.playful-site.academic-site :is(.pathway-actions, .test-preparation-cards > article) {
    min-width: 0;
  }
  body.playful-site.academic-site
    :is(.pathway-primary, .pathway-secondary, .test-preparation-cards > article > .button, .program-card > .button) {
    box-sizing: border-box;
    width: 100%;
    min-width: 0;
    max-width: 100%;
    overflow-wrap: anywhere;
  }

  /* Portrait actions use their own row. This remains stable when iPad Safari
     keeps a desktop-width layout viewport or applies enlarged text. */
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card {
    grid-template-columns: 88px minmax(0, 1fr);
    grid-template-rows: auto auto auto auto auto;
    min-height: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-card-top {
    grid-column: 1;
    grid-row: 1 / 5;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > :is(.grade, h3, p:not(.grade), .pathway-details) {
    grid-column: 2;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    display: grid;
    grid-column: 1 / -1;
    grid-row: 5;
    grid-template-columns: minmax(150px, 190px) minmax(0, 1fr);
    align-items: center;
    gap: 10px 18px;
    margin-top: 8px;
    padding-top: 12px;
    border-top: 1px solid #d8dfe2;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways
    :is(.pathway-primary, .pathway-secondary) {
    width: auto;
    max-width: 100%;
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article,
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    grid-template-columns: 82px minmax(0, 1fr);
    grid-template-rows: auto auto auto;
    height: auto;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > h2 {
    grid-column: 1;
    grid-row: 1 / 3;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > p {
    grid-column: 2;
    grid-row: 1;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > ul {
    grid-column: 2;
    grid-row: 2;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > .button {
    grid-column: 1 / -1;
    grid-row: 3;
    justify-self: start;
    width: auto;
    min-width: 170px;
    margin-top: 8px;
  }
}

/* Safari rotation fallback. The class is derived from the live viewport size,
   so a landscape-to-portrait turn cannot retain the previous column layout. */
@media (min-width: 744px) and (max-width: 1400px) {
  html.ipad-portrait body.playful-site.academic-site.home-page .hero,
  html.ipad-portrait body.playful-site.academic-site :is(.competition-hero, .course-hero-grid, .club-hero) {
    grid-template-columns: minmax(0, 1fr);
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .hero {
    gap: 24px;
    padding: 32px var(--tablet-gutter) 36px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .hero-copy { max-width: 620px; }
  html.ipad-portrait body.playful-site.academic-site.home-page .hero-problem {
    width: min(500px, 100%);
    justify-self: center;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .problem-card { padding: 16px; }
  html.ipad-portrait body.playful-site.academic-site .competition-hero,
  html.ipad-portrait body.playful-site.academic-site .club-hero { gap: 24px; }
  html.ipad-portrait body.playful-site.academic-site .club-hero {
    width: calc(100% - (2 * var(--tablet-gutter)));
    padding-block: 32px;
  }

  html.ipad-portrait body.playful-site.academic-site :is(.content-grid, .info-grid, .stage-grid) {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  html.ipad-portrait body.playful-site.academic-site
    :is(.content-grid, .info-grid, .stage-grid) > :last-child:nth-child(odd) {
    grid-column: 1 / -1;
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards {
    grid-template-columns: minmax(0, 1fr);
    grid-auto-rows: 1fr;
    gap: 13px;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article,
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    display: grid;
    grid-column: auto;
    grid-template-columns: 82px minmax(0, 1fr);
    grid-template-rows: auto auto auto;
    align-items: center;
    gap: 7px 14px;
    min-height: 206px;
    height: 100%;
    padding: 16px;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > h2 {
    grid-column: 1;
    grid-row: 1 / 3;
    min-height: 0;
    margin: 0;
    padding-right: 14px;
    border-right: 1px solid #c8d3dc;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > p {
    grid-column: 2;
    grid-row: 1;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > ul {
    grid-column: 2;
    grid-row: 2;
    margin: 0;
    padding-left: 18px;
  }
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > .button {
    grid-column: 1 / -1;
    grid-row: 3;
    justify-self: start;
    width: auto;
    min-width: 170px;
    max-width: 100%;
    margin: 8px 0 0;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 13px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card {
    display: grid;
    grid-template-columns: 88px minmax(0, 1fr);
    grid-template-rows: auto auto auto auto auto;
    gap: 5px 14px;
    min-height: 172px;
    height: 100%;
    padding: 15px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-card-top {
    grid-column: 1;
    grid-row: 1 / 5;
    align-self: start;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > .grade {
    grid-column: 2;
    grid-row: 1;
    min-height: 0;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > h3 {
    grid-column: 2;
    grid-row: 2;
    width: auto;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > p:not(.grade) {
    grid-column: 2;
    grid-row: 3;
    width: auto;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-details {
    grid-column: 2;
    grid-row: 4;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 0;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    display: grid;
    grid-column: 1 / -1;
    grid-row: 5;
    grid-template-columns: minmax(150px, 190px) minmax(0, 1fr);
    align-items: center;
    gap: 10px 18px;
    width: 100%;
    height: auto;
    min-height: 0;
    max-height: none;
    margin: 8px 0 0;
    padding-top: 12px;
    border-top: 1px solid #d8dfe2;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways
    :is(.pathway-primary, .pathway-secondary) {
      width: auto;
      min-width: 0;
      max-width: 100%;
    }

  html.ipad-portrait body.playful-site.academic-site .unit-layout {
    grid-template-columns: 195px minmax(0, 1fr);
    gap: 20px;
  }
  html.ipad-portrait body.playful-site.academic-site .practice-layout {
    grid-template-columns: minmax(0, 1fr);
  }
  html.ipad-portrait body.playful-site.academic-site .review-sidebar { order: -1; }
  html.ipad-portrait body.playful-site.academic-site.home-page .footer-main {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.35fr);
    gap: 28px 42px;
  }
  html.ipad-portrait body.playful-site.academic-site.home-page .footer-main > div:first-child {
    grid-column: 1 / -1;
  }
}

/* Final compact iPad scale. Form controls intentionally stay at 16px so iOS
   does not zoom the viewport when a field receives focus. */
@media (min-width: 744px) and (max-width: 1400px) {
  html { font-size: 12px; }
  body.playful-site.academic-site {
    --tablet-space: clamp(30px, 3.7vw, 42px);
    font-size: 11px;
    line-height: 1.52;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    height: 58px;
    min-height: 58px;
    padding-block: 5px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    height: 44px;
    max-height: 44px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) nav a {
    font-size: 11px;
  }
  body.playful-site.academic-site :is(.mobile-nav-toggle, .site-header .menu-toggle) {
    width: 36px;
    min-width: 36px;
    height: 36px;
    min-height: 36px;
    padding: 7px;
  }
  body.playful-site.academic-site
    :is(.page-hero, .content-hero, .competition-hero, .science-hero, .school-hero) {
    padding-block: 28px;
  }
  body.playful-site.academic-site
    :is(.page-hero h1, .content-hero h1, .competition-hero h1, .science-hero h1, .school-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1) {
    margin-block: 6px 10px;
    font-size: clamp(22px, 2.45vw, 29px);
  }
  body.playful-site.academic-site.home-page .hero .home-hero-title {
    font-size: clamp(22px, 2.5vw, 30px);
  }
  body.playful-site.academic-site main h2 { font-size: clamp(18px, 1.95vw, 23px); }
  body.playful-site.academic-site main h3 { font-size: 13.5px; }
  body.playful-site.academic-site main
    :is(p, li):not(.kicker):not(.eyebrow):not(.club-kicker):not(.contest-tag):not(.grade):not(.study-label) {
    font-size: 11px;
  }
  body.playful-site.academic-site
    :is(.kicker, .eyebrow, .club-kicker, .contest-tag, .study-label, .problem-top, .problem-label, .problem-foot) {
    font-size: 9px;
  }
  body.playful-site.academic-site
    :is(.button, .a-button, .club-button, .text-link, .text-action, .pathway-primary, .pathway-secondary) {
    min-height: 36px;
    padding: 7px 10px;
    font-size: 10px;
  }
  body.playful-site.academic-site
    :is(.program-grid, .info-grid, .content-grid, .pathway-cards, .stage-grid, .contest-grid, .club-duo) {
    gap: 13px;
  }
  body.playful-site.academic-site
    :is(.program-card, .info-card, .course-card, .contest-card, .stage-grid article, .pathway-cards > a, .content-grid article, .club-duo article, .assessment-card, .sample-card, .unit-detail, .system-panel, .trial-form, .inquiry-form) {
    padding: 14px;
  }
  body.playful-site.academic-site .system-flow > div {
    min-height: 68px;
    padding: 9px 6px;
  }
  body.playful-site.academic-site .simple-footer,
  body.playful-site.academic-site :is(.site-footer, .club-footer, .course-footer) {
    padding-block: 18px;
    font-size: 10.5px;
  }
}

@media (min-width: 744px) and (max-width: 1040px) and (orientation: portrait) {
  body.playful-site.academic-site {
    --tablet-gutter: clamp(28px, 3.8vw, 34px);
    --tablet-space: 34px;
    font-size: 11.5px;
  }
  body.playful-site.academic-site.home-page .hero {
    gap: 24px;
    padding: 32px var(--tablet-gutter) 36px;
  }
  body.playful-site.academic-site.home-page .hero-problem { width: min(500px, 100%); }
  body.playful-site.academic-site.home-page .problem-card { padding: 16px; }
  body.playful-site.academic-site.home-page .home-pathways .program-card {
    grid-template-columns: 62px minmax(0, 1fr) 154px;
    gap: 5px 14px;
    min-height: 172px;
    padding: 15px;
  }
  body.playful-site.academic-site .test-preparation-cards > article,
  body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    grid-template-columns: 78px minmax(0, 1fr) 146px;
    gap: 7px 14px;
    min-height: 206px;
    padding: 16px;
  }
  body.playful-site.academic-site .club-hero { gap: 24px; padding-block: 32px; }
  body.playful-site.academic-site .club-notebook { padding: 16px; }
  body.playful-site.academic-site .club-question { padding-block: 9px; font-size: 16px; }
  body.playful-site.academic-site .unit-layout {
    grid-template-columns: 195px minmax(0, 1fr);
    gap: 20px;
  }
}

@media (min-width: 900px) and (max-width: 1400px) and (orientation: landscape) {
  html { font-size: 11.5px; }
  body.playful-site.academic-site {
    --tablet-space: clamp(27px, 3.2vw, 36px);
    font-size: 10.5px;
  }
  body.playful-site.academic-site.home-page .hero {
    gap: clamp(26px, 3.2vw, 42px);
    padding-block: 29px 32px;
  }
  body.playful-site.academic-site.home-page .hero-problem { width: min(400px, 100%); }
  body.playful-site.academic-site.home-page .problem-card { padding: 14px; }
  body.playful-site.academic-site .test-preparation-cards > article > .button {
    height: 36px;
    min-height: 36px;
    max-height: 36px;
    font-size: 10px;
  }
  body.playful-site.academic-site .club-hero { gap: 28px; padding-block: 29px; }
  body.playful-site.academic-site .club-notebook { padding: 14px; }
  body.playful-site.academic-site .club-question { padding-block: 8px; font-size: 15px; }
  body.playful-site.academic-site .course-hero { padding-block: 20px 24px; }
  body.playful-site.academic-site .breadcrumb { margin-bottom: 20px; }
}

@media (min-width: 1251px) and (max-width: 1400px) and (orientation: landscape) {
  body.playful-site.academic-site :is(.mobile-nav-toggle, .site-header .menu-toggle) {
    display: none;
  }
}


/* ===== 原模块：editorial-refresh.css ===== */
/* 官网后加载的版式覆盖；依赖已有主题变量。修改时保留页面中样式表的加载顺序。 */
/* A quieter, human-made academic presentation.
   Layout remains page-specific; this layer only simplifies the visual language. */
body.playful-site.academic-site {
  --ink: #17324d;
  --blue: #17324d;
  --orange: #275f8c;
  --gold: #a58b59;
  --soft: #f3f5f4;
  --line: #d4dcdF;
  --muted: #536574;
  --paper: #fbfaf7;
  background-color: #fbfaf7;
  background-image: none;
}

/* The repeated formula wallpaper made every page feel generated. Keep the
   mathematics in the actual content and examples instead. */
body.playful-site.academic-site
  :is(.hero, .page-hero, .content-hero, .science-hero, .school-hero, .course-hero, .store-hero, .competition-hero, .algebra-hero, .club-hero, .programs, .bookstore, .v2-programs, .method, .stories, .program-band, .home-club, .trial, .page-cta, .club-closing, .competition-section, .practice-section, .modeling-section, .semester-section, .private-support, .alignment-section) {
  background-image: none !important;
}

body.playful-site.academic-site
  :is(.hero, .page-hero, .content-hero, .science-hero, .school-hero, .course-hero, .store-hero, .competition-hero, .algebra-hero, .club-hero) {
  background: #edf2f4;
  border-bottom: 1px solid #cfd9df;
}

body.playful-site.academic-site
  :is(.v2-programs, .method, .stories, .program-band.light, .home-club, .trial, .page-cta, .competition-section.tinted, .practice-section, .modeling-section, .semester-section, .private-support, .alignment-section) {
  background-color: #f4f3ee;
}

body.playful-site.academic-site
  :is(.hero h1, .page-hero h1, .content-hero h1, .science-hero h1, .school-hero h1, .competition-hero h1, .algebra-hero h1, .course-hero h1, .club-hero h1, .v2-heading h2, .section-heading h2, .page-intro h2, .program-copy h2, .method h2, .trial h2, .page-cta h2) {
  font-family: "DM Sans", Arial, sans-serif;
  font-weight: 700;
  letter-spacing: -.025em;
}

body.playful-site.academic-site
  :is(.eyebrow, .kicker, .club-kicker, .contest-tag, .study-label) {
  text-transform: none;
  letter-spacing: .055em;
  font-weight: 650;
}

/* Flat, useful surfaces instead of a repeated floating-card effect. */
body.playful-site.academic-site
  :is(.home-pathways .program-card, .program-card, .book-card, .story-grid blockquote, .info-card, .content-grid article, .pathway-cards > a, .v2-program-grid > a, .v2-five > article, .course-card, .level-pathway article, .two-column-details article, .club-duo article, .stage-grid article, .contest-card, .sample-card, .assessment-card, .schedule-card, .confirmation-card, .account-record, .account-stats article, .account-admin-grid > section, .student-list article, .admin-area-grid > a, .login-card, .registration-card, .overview article, .setup-card, .panel, .catalog-card, .hero-study, .worked-example, .unit-detail, .organizer-intro, .cms-contests, .school-hero aside, .problem-card, .club-notebook, .study-paper, .alignment-form, .trial-form, .inquiry-form, .account-login, .enrol-summary, .placement-help, .lesson-card, .preview-note, .review-sidebar, .common-mistake, .next-review, .catalog-filters),
body.playful-site.academic-site.registration-result-page #confirmation {
  border-radius: 3px;
  box-shadow: none;
  transform: none;
}

body.playful-site.academic-site
  :is(.home-pathways .program-card, .program-card, .book-card, .story-grid blockquote, .info-card, .content-grid article, .pathway-cards > a, .v2-program-grid > a, .v2-five > article, .course-card, .level-pathway article, .two-column-details article, .club-duo article, .stage-grid article, .contest-card, .sample-card, .assessment-card, .catalog-card):hover {
  box-shadow: none;
  transform: none;
}

body.playful-site.academic-site
  :is(.home-pathways .program-card, .program-card, .book-card, .story-grid blockquote, .info-card, .content-grid article, .pathway-cards > a, .v2-program-grid > a, .v2-five > article, .course-card, .level-pathway article, .two-column-details article, .club-duo article, .stage-grid article, .contest-card, .assessment-card) {
  background: #fff;
  border-color: #cfd8de;
}

body.playful-site.academic-site :is(.button, .a-button, .club-button) {
  border-radius: 3px;
  background: #1c3a52;
  border-color: #1c3a52;
  box-shadow: none;
  color: #fff;
  transform: none;
}
body.playful-site.academic-site :is(.button, .a-button, .club-button):hover {
  background: #285873;
  border-color: #285873;
  box-shadow: none;
  color: #fff;
  transform: none;
}

body.playful-site.academic-site :is(.hero, .page-hero)::after,
body.playful-site.academic-site :is(.content-hero, .science-hero, .school-hero)::after {
  display: none;
}

body.playful-site.academic-site .problem-card {
  background: #f8fbfc;
  border-top-color: #365c73;
}
body.playful-site.academic-site .club-notebook { background: #f7f8f3; }

/* Color identifies sections through a restrained rule, not a different pastel
   fill on every card. */
body.playful-site.academic-site
  :is(.home-pathways .program-card, .content-grid article, .info-card, .stage-grid article) {
  border-top-width: 2px;
}

@media (hover: hover) and (pointer: fine) {
  body.playful-site.academic-site
    :is(.home-pathways .program-card, .program-card, .book-card, .info-card, .content-grid article, .pathway-cards > a, .v2-program-grid > a, .course-card, .contest-card, .catalog-card):hover {
    border-color: #7894a6;
  }
}

/* Desktop should feel like a working school site, not an oversized landing-page
   template. Tablet and phone retain their dedicated dimensions. */
@media (min-width: 1367px) {
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) {
    height: 84px;
    min-height: 84px;
    padding-block: 7px;
  }
  body.playful-site.academic-site
    :is(.site-header, .simple-header, .algebra-header, .club-header, .course-header) .brand-logo {
    width: auto;
    height: 66px;
    max-height: 66px;
  }
  body.playful-site.academic-site.home-page .hero {
    min-height: 0;
    padding-block: 68px;
  }
  body.playful-site.academic-site
    :is(.page-hero, .content-hero, .science-hero, .school-hero) {
    padding-block: 62px;
  }
  body.playful-site.academic-site
    :is(.section, .page-wrap, .content-wrap, .competition-section, .trial, .v2-programs, .v2-system) {
    padding-block: 64px;
  }
}

/* Present the learning process as an editorial sequence, not five floating
   feature cards. */
body.playful-site.academic-site.home-page .v2-five {
  gap: 0;
  border-block: 1px solid #c8d3d9;
}
body.playful-site.academic-site.home-page .v2-five > article,
body.playful-site.academic-site.home-page .v2-five > article:hover {
  padding: 22px 18px;
  background: transparent;
  border: 0;
  border-left: 1px solid #d8dfe2;
  border-radius: 0;
  box-shadow: none;
}
body.playful-site.academic-site.home-page .v2-five > article:first-child { border-left: 0; }
body.playful-site.academic-site.home-page .v2-five h3 { margin-top: 8px; }

/* The final routes are reading links rather than another repeated card set. */
body.playful-site.academic-site.home-page .story-grid { gap: 28px; }
body.playful-site.academic-site.home-page .story-grid blockquote,
body.playful-site.academic-site.home-page .story-grid blockquote:hover {
  padding: 22px 0 0;
  background: transparent;
  border: 0;
  border-top: 2px solid #627f90;
  border-radius: 0;
  box-shadow: none;
}
body.playful-site.academic-site.home-page .story-grid blockquote footer {
  width: auto;
  border-top: 1px solid #d4dcdf;
}

@media (min-width: 621px) and (max-width: 1040px) and (orientation: portrait) {
  body.playful-site.academic-site.home-page .v2-five { grid-template-columns: minmax(0, 1fr); }
  body.playful-site.academic-site.home-page .v2-five > article,
  body.playful-site.academic-site.home-page .v2-five > article:first-child {
    display: grid;
    grid-template-columns: 34px max-content minmax(0, 1fr);
    grid-template-rows: auto auto;
    gap: 3px 12px;
    padding: 15px 8px;
    border-left: 0;
    border-top: 1px solid #d8dfe2;
  }
  body.playful-site.academic-site.home-page .v2-five > article:first-child { border-top: 0; }
  body.playful-site.academic-site.home-page .v2-five b { grid-column: 1; grid-row: 1 / 3; }
  body.playful-site.academic-site.home-page .v2-five h3 { grid-column: 2; grid-row: 1 / 3; margin: 0; }
  body.playful-site.academic-site.home-page .v2-five strong { grid-column: 3; grid-row: 1; }
  body.playful-site.academic-site.home-page .v2-five p { grid-column: 3; grid-row: 2; margin: 0; }
}

@media (max-width: 620px) {
  body.playful-site.academic-site.home-page .v2-five { grid-template-columns: minmax(0, 1fr); }
  body.playful-site.academic-site.home-page .v2-five > article,
  body.playful-site.academic-site.home-page .v2-five > article:first-child {
    display: grid;
    /* 手机上给步骤名称完整一行，说明另起两行，避免英文单词被窄列拆开。 */
    grid-template-columns: 36px minmax(0, 1fr);
    grid-template-rows: auto auto auto;
    gap: 8px 12px;
    padding: 14px 0;
    border-left: 0;
    border-top: 1px solid #d8dfe2;
  }
  body.playful-site.academic-site.home-page .v2-five > article:first-child { border-top: 0; }
  body.playful-site.academic-site.home-page .v2-five b { grid-column: 1; grid-row: 1; }
  body.playful-site.academic-site.home-page .v2-five h3 { grid-column: 2; grid-row: 1; align-self: center; margin: 0; white-space: nowrap; }
  body.playful-site.academic-site.home-page .v2-five strong { grid-column: 1 / -1; grid-row: 2; margin-top: 4px; }
  body.playful-site.academic-site.home-page .v2-five p { grid-column: 1 / -1; grid-row: 3; margin: 0; }
  body.playful-site.academic-site.home-page .story-grid { gap: 22px; }
}


/* Algebra 1 / 2 共用排版约定，不为某一个课程单独覆盖字号或间距。 */
body.playful-site.academic-site.algebra-page .course-pair > .course-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
}
body.playful-site.academic-site.algebra-page .course-pair .course-topic-list { flex: 1; margin-bottom: 24px; }
body.playful-site.academic-site.algebra-page .course-pair .a-button { margin-top: auto; min-height: 48px; }
body.playful-site.academic-site.algebra-course-page :is(.unit-detail h2, .section-intro h2) {
  font-size: clamp(22px, 2vw, 28px);
  line-height: 1.3;
  letter-spacing: -.02em;
}
body.playful-site.academic-site.algebra-course-page :is(.sample-card h3, .assessment-card h3, .review-sidebar h3, .lesson-card h3) {
  font-size: 18px;
  line-height: 1.4;
}
body.playful-site.academic-site.algebra-course-page :is(.button, .explorer-tabs > button, .course-switch a) {
  min-height: 48px;
  line-height: 1.5;
}
body.playful-site.academic-site.algebra-course-page .sample-nav { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
body.playful-site.academic-site.algebra-course-page .sample-nav > button { min-width: 0; white-space: normal; }
body.playful-site.academic-site.algebra-course-page .answer-option { min-width: 0; }
body.playful-site.academic-site.algebra-course-page .answer-option > span { min-width: 0; }

/* Algebra 手机课程预览：流程不掉行，较长的单元标题使用整行空间。 */
@media (max-width: 620px) {
  body.playful-site.academic-site.algebra-course-page .course-container { width: calc(100% - 32px); }
  body.playful-site.academic-site.algebra-course-page :is(.unit-detail, .sample-card, .review-sidebar, .assessment-card) { padding: 20px; }
  body.playful-site.academic-site.algebra-course-page :is(.unit-description, .section-intro p, .preview-note) { font-size: 14px; line-height: 1.7; }
  body.playful-site.academic-site.algebra-course-page .unit-actions { gap: 14px; }
  body.playful-site.academic-site.algebra-course-page :is(.unit-actions, .question-controls) > .button { width: 100%; }
  body.playful-site.academic-site.algebra-course-page .course-switch { max-width: none; }
  body.playful-site.academic-site.algebra-course-page .course-switch a { padding: 12px; gap: 8px; white-space: nowrap; }
  body.playful-site.academic-site .course-path {
    display: grid;
    grid-template-columns: repeat(5, minmax(max-content, 1fr));
    gap: 4px;
    width: 100%;
  }
  body.playful-site.academic-site .course-path > i { display: none; }
  body.playful-site.academic-site .course-path > span {
    min-width: 0;
    padding: 8px 0;
    font-size: 12px;
    line-height: 1.4;
    letter-spacing: 0;
    text-transform: none;
    text-align: center;
    white-space: nowrap;
    border-bottom: 2px solid #b9c9d8;
  }
  body.playful-site.academic-site .unit-list { display: grid; grid-template-columns: minmax(0, 1fr); gap: 8px; }
  body.playful-site.academic-site .unit-list > button {
    display: grid;
    grid-template-columns: 28px minmax(0, 1fr);
    align-items: center;
    gap: 10px;
    width: 100%;
    min-height: 54px;
    padding: 12px;
    font-size: 14px;
    line-height: 1.5;
    text-align: left;
    border: 1px solid #d7e0e7;
    border-radius: 8px;
  }
  body.playful-site.academic-site .unit-list > button span:last-child { min-width: 0; word-break: normal; overflow-wrap: normal; }
  body.playful-site.academic-site .explorer-tabs { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  body.playful-site.academic-site .explorer-tabs > button { min-height: 56px; padding: 10px 8px; font-size: 13px; line-height: 1.4; white-space: normal; }
}

/* ===== 原模块：ipad-portrait.css ===== */
/* 平板竖屏专用覆盖；配合 mobile-navigation.js 的方向类名。修改时保留页面中样式表的加载顺序。 */
/* Dedicated iPad portrait composition.
   This layer intentionally loads last and does not share card geometry with
   landscape. The live ipad-portrait class also supports Safari desktop mode. */
@media (min-width: 700px) and (max-width: 1400px) {
  html.ipad-portrait {
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
  }

  html.ipad-portrait body.playful-site.academic-site {
    --tablet-gutter: clamp(28px, 4.2vw, 44px);
    --tablet-space: clamp(30px, 4.4vw, 48px);
  }

  html.ipad-portrait body.playful-site.academic-site
    :is(.hero, .competition-hero, .course-hero-grid, .club-hero, .section-heading) {
    grid-template-columns: minmax(0, 1fr);
  }

  html.ipad-portrait body.playful-site.academic-site
    :is(.program-grid, .test-preparation-cards, .content-grid, .info-grid, .stage-grid, .pathway-cards, .contest-grid, .club-duo) {
    grid-template-columns: minmax(0, 1fr);
    grid-auto-rows: auto;
    align-items: stretch;
  }

  html.ipad-portrait body.playful-site.academic-site .stage-grid {
    grid-auto-rows: 1fr;
  }

  html.ipad-portrait body.playful-site.academic-site .stage-grid > article {
    display: flex;
    flex-direction: column;
    height: 100%;
    min-height: 270px;
  }

  html.ipad-portrait body.playful-site.academic-site .stage-grid > article > a:last-child {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    box-sizing: border-box;
    width: min(280px, 100%);
    min-width: 0;
    max-width: 100%;
    height: 42px;
    min-height: 42px;
    margin-top: auto;
    padding: 0 14px;
    color: #fff;
    background: #203f54;
    border: 1px solid #203f54;
    border-radius: 4px;
    font-size: 11px;
    line-height: 1.2;
    white-space: nowrap;
  }

  html.ipad-portrait body.playful-site.academic-site
    :is(.program-grid, .test-preparation-cards, .content-grid, .info-grid, .stage-grid, .pathway-cards, .contest-grid, .club-duo) > * {
    grid-column: auto;
    width: 100%;
    min-width: 0;
    max-width: 100%;
    height: auto;
    min-height: 0;
    box-sizing: border-box;
  }

  /* Homepage stages use a calm, vertical reading order. */
  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card {
    display: flex;
    flex-direction: column;
    gap: 0;
    width: 100%;
    min-width: 0;
    min-height: 0;
    height: auto;
    padding: clamp(18px, 2.6vw, 26px);
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-card-top {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: flex-start;
    gap: 12px;
    margin: 0 0 14px;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-symbol {
    flex: 0 0 auto;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-step {
    white-space: nowrap;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > :is(.grade, h3, p:not(.grade), .pathway-details) {
    width: 100%;
    min-width: 0;
    max-width: 100%;
    height: auto;
    min-height: 0;
    max-height: none;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > .grade {
    margin: 0 0 8px;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > h3 {
    margin: 0 0 10px;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .program-card > p:not(.grade) {
    margin: 0 0 12px;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-details {
    margin: 0;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways .pathway-actions {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    width: 100%;
    min-width: 0;
    max-width: 100%;
    height: auto;
    min-height: 0;
    margin: 16px 0 0;
    padding: 14px 0 0;
    border-top: 1px solid #d8dfe2;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .home-pathways
    :is(.pathway-primary, .pathway-secondary) {
    box-sizing: border-box;
    width: min(240px, 100%);
    min-width: 0;
    max-width: 100%;
    margin: 0;
    white-space: normal;
    overflow-wrap: anywhere;
  }

  /* Test-preparation cards follow the same vertical rhythm. */
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article,
  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article:last-child:nth-child(odd) {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 12px;
    width: 100%;
    min-width: 0;
    max-width: 100%;
    height: auto;
    min-height: 0;
    padding: clamp(18px, 2.6vw, 26px);
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > h2 {
    width: 100%;
    min-width: 0;
    min-height: 0;
    margin: 0;
    padding: 0 0 10px;
    border-right: 0;
    border-bottom: 1px solid #c8d3dc;
    white-space: normal;
    overflow-wrap: anywhere;
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > :is(p, ul) {
    width: 100%;
    min-width: 0;
    max-width: 100%;
    margin: 0;
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > ul {
    padding-left: 20px;
  }

  html.ipad-portrait body.playful-site.academic-site .test-preparation-cards > article > .button {
    align-self: flex-start;
    box-sizing: border-box;
    width: min(240px, 100%);
    min-width: 0;
    max-width: 100%;
    height: auto;
    min-height: 38px;
    max-height: none;
    margin: 4px 0 0;
    white-space: normal;
    overflow-wrap: anywhere;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .v2-five {
    grid-template-columns: minmax(0, 1fr);
  }

  html.ipad-portrait body.playful-site.academic-site .unit-layout,
  html.ipad-portrait body.playful-site.academic-site .practice-layout {
    grid-template-columns: minmax(0, 1fr);
  }

  html.ipad-portrait body.playful-site.academic-site .review-sidebar {
    order: -1;
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .footer-main {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  html.ipad-portrait body.playful-site.academic-site.home-page .footer-main > div:first-child {
    grid-column: 1 / -1;
  }
}