:root {
  --platform-ink: #243849;
  --platform-muted: #68767d;
  --platform-paper: #fffdf8;
  --platform-sand: #fff7e8;
  --platform-line: #ece1ce;
  --platform-orange: #ef9b45;
  --platform-orange-dark: #c46f27;
  --platform-green: #3c917b;
  --platform-blue: #6faac3;
  --platform-shadow: 0 12px 32px rgba(80, 58, 30, .10);
  --platform-radius: 20px;
}

* { box-sizing: border-box; }
html { background: var(--platform-paper); }
body {
  margin: 0;
  min-width: 320px;
  color: var(--platform-ink);
  background: linear-gradient(180deg, #fffdf8 0%, #fff9ef 100%);
  font-family: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
}
button, input, select { font: inherit; }
a { color: inherit; }

.platform-shell {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid var(--platform-line);
  background: rgba(255, 253, 248, .96);
  backdrop-filter: blur(14px);
}
.platform-shell__inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 18px;
  width: min(1120px, calc(100% - 32px));
  min-height: 76px;
  margin: 0 auto;
}
.platform-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  text-decoration: none;
  font-weight: 800;
  letter-spacing: .03em;
  white-space: nowrap;
}
.platform-brand__mark {
  display: grid;
  width: 38px;
  height: 38px;
  flex: 0 0 auto;
  place-items: center;
  overflow: hidden;
  border: 1px solid #f2e6d2;
  border-radius: 12px;
  background: #fff;
}
.platform-brand__mark img { width: 30px; height: 30px; object-fit: contain; }
.platform-brand__text { overflow: hidden; text-overflow: ellipsis; }
.platform-menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--platform-line);
  border-radius: 13px;
  background: #fff;
  color: var(--platform-ink);
  font-size: 1.25rem;
  font-weight: 900;
  line-height: 1;
  cursor: pointer;
}
.platform-menu-toggle:focus-visible, .platform-account:focus-visible, .platform-nav a:focus-visible, .platform-brand:focus-visible, .button-primary:focus-visible, .button-secondary:focus-visible {
  outline: 3px solid rgba(60, 145, 123, .42);
  outline-offset: 3px;
}
.platform-sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.platform-nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.platform-nav a {
  padding: 9px 11px;
  border-radius: 10px;
  color: #435661;
  font-size: .92rem;
  font-weight: 700;
  text-decoration: none;
}
.platform-nav a:hover, .platform-nav a[aria-current="page"] { color: var(--platform-orange-dark); background: #fff2dc; }
.platform-account {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 95px;
  padding: 10px 14px;
  border: 0;
  border-radius: 12px;
  background: var(--platform-orange);
  color: white;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
}
.platform-account:hover { background: var(--platform-orange-dark); }

.platform-footer { margin-top: 0; padding: 38px 0 34px; background: var(--platform-ink); color: #dce7e9; }
.platform-footer__inner { display: flex; flex-direction: column; gap: 16px; width: min(1120px, calc(100% - 32px)); margin: 0 auto; }
.platform-footer__brand { display: inline-flex; align-items: center; gap: 9px; color: #fff; font-weight: 800; }
.platform-footer__brand img { width: 30px; height: 30px; border-radius: 50%; background: #fff; }
.platform-footer__links { display: flex; flex-wrap: wrap; gap: 10px 18px; }
.platform-footer__links a { color: #dce7e9; font-size: .9rem; font-weight: 700; text-decoration: none; }
.platform-footer__links a:hover { color: #fff; }
.platform-footer p { max-width: 760px; margin: 0; color: #aebfc5; font-size: .8rem; line-height: 1.75; }

.learn-page { width: min(1120px, calc(100% - 32px)); margin: 0 auto; padding: 42px 0 72px; }
.learn-hero { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(260px, .8fr); gap: 24px; align-items: stretch; }
.learn-hero__copy {
  position: relative;
  min-height: 350px;
  padding: clamp(24px, 4vw, 46px);
  overflow: hidden;
  border: 1px solid #f2dfbf;
  border-radius: calc(var(--platform-radius) + 8px);
  background:
    radial-gradient(circle at 12% 12%, rgba(255, 220, 167, .72) 0 2px, transparent 3px),
    radial-gradient(circle at 30% 28%, rgba(126, 188, 167, .38) 0 3px, transparent 4px),
    radial-gradient(circle at 56% 13%, rgba(255, 195, 115, .48) 0 2px, transparent 3px),
    linear-gradient(135deg, #fff9ef 0%, #fff2dd 55%, #f8f5e9 100%);
  box-shadow: var(--platform-shadow);
}
.learn-hero__copy > *:not(.learn-hero__character) { position: relative; z-index: 1; }
.learn-hero__character {
  position: absolute;
  right: clamp(-14px, 1vw, 8px);
  bottom: -4px;
  z-index: 0;
  width: min(42%, 255px);
  pointer-events: none;
  filter: drop-shadow(0 18px 12px rgba(102, 66, 25, .10));
}
.learn-hero__character img { display: block; width: 100%; height: auto; }
.learn-eyebrow { display: inline-flex; align-items: center; gap: 7px; margin: 0 0 12px; color: var(--platform-green); font-size: .88rem; font-weight: 800; }
h1 { max-width: 720px; margin: 0; color: var(--platform-ink); font-size: clamp(2rem, 5vw, 3.5rem); line-height: 1.16; letter-spacing: -.04em; }
.learn-lead { max-width: 670px; margin: 18px 0 0; color: var(--platform-muted); font-size: 1.1rem; line-height: 1.75; }
.card { border: 1px solid var(--platform-line); border-radius: var(--platform-radius); background: #fff; box-shadow: var(--platform-shadow); }
.today-card { display: flex; flex-direction: column; min-height: 100%; padding: 26px; background: linear-gradient(135deg, #fff1da, #fffdf8); }
.today-card__tag, .course-card__status { display: inline-flex; align-self: flex-start; padding: 6px 10px; border-radius: 999px; font-size: .78rem; font-weight: 800; }
.today-card__tag { background: #fff; color: var(--platform-orange-dark); }
.today-card h2 { margin: 18px 0 8px; font-size: 1.35rem; line-height: 1.4; }
.today-card p { margin: 0; color: var(--platform-muted); line-height: 1.65; }
.button-primary, .button-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 50px;
  margin-top: 20px;
  padding: 12px 18px;
  border-radius: 14px;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
}
.button-primary { border: 0; background: linear-gradient(180deg, #f7ab5c, #eb8c38); box-shadow: inset 0 -4px 0 rgba(131, 65, 15, .25); color: #fff; }
.button-primary:hover { filter: brightness(.97); }
.button-secondary { border: 1px solid #ddd2bd; background: #fff; color: var(--platform-ink); }
.button-secondary:hover { background: #fff8ee; }
.today-card .button-primary { margin-top: auto; }

.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 16px; margin: 50px 0 18px; }
.section-heading h2 { margin: 0; font-size: 1.45rem; }
.section-heading p { margin: 0; color: var(--platform-muted); font-size: .94rem; }
.course-grid { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 14px; }
.course-card { display: flex; min-height: 220px; flex-direction: column; padding: 20px; text-decoration: none; }
.course-card__icon { display: grid; width: 48px; height: 48px; place-items: center; border-radius: 15px; font-size: 1.55rem; }
.course-card h3 { margin: 18px 0 6px; font-size: 1.05rem; }
.course-card p { margin: 0; color: var(--platform-muted); font-size: .88rem; line-height: 1.55; }
.course-card__status { margin-top: auto; }
.course-card--active { border-color: #f5cea1; }
.course-card--active .course-card__icon { background: #fff0da; }
.course-card--active .course-card__status { background: #e8f6f1; color: #25715e; }
.course-card--planned { opacity: .9; }
.course-card--planned .course-card__icon { background: #f0f4f5; }
.course-card--planned .course-card__status { background: #f2f2f1; color: #6c7477; }
.course-card--active:hover { transform: translateY(-2px); box-shadow: var(--platform-shadow); }

.notice { display: flex; gap: 12px; margin-top: 28px; padding: 18px 20px; border: 1px solid #cce5dc; border-radius: 16px; background: #f2faf6; color: #335c50; line-height: 1.6; }
.notice strong { display: block; margin-bottom: 2px; }
.learn-loading { padding: 56px 20px; color: var(--platform-muted); text-align: center; }
.hide { display: none !important; }

@media (max-width: 860px) {
  .platform-shell__inner { min-height: 66px; gap: 8px; width: min(100% - 24px, 1120px); }
  .platform-brand__text { font-size: .92rem; }
  .platform-menu-toggle { display: inline-flex; margin-left: auto; }
  .platform-nav {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 8px;
    border: 1px solid var(--platform-line);
    border-radius: 16px;
    background: rgba(255, 253, 248, .99);
    box-shadow: var(--platform-shadow);
  }
  .platform-shell--menu-open .platform-nav { display: flex; }
  .platform-nav a { width: 100%; padding: 12px 13px; }
  .platform-account { min-width: 74px; padding: 9px 10px; font-size: .86rem; }
  .platform-footer__inner { width: min(100% - 24px, 1120px); }
  .learn-page { width: min(100% - 24px, 1120px); padding: 28px 0 52px; }
  .learn-hero { grid-template-columns: 1fr; }
  .learn-hero__copy { min-height: 312px; padding: 28px 24px 138px; }
  .learn-hero__character { width: min(42vw, 190px); right: 4px; }
  .learn-lead { max-width: 90%; }
  .course-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course-card { min-height: 185px; }
}
@media (max-width: 430px) {
  .platform-brand__mark { width: 34px; height: 34px; }
  .platform-brand__mark img { width: 27px; height: 27px; }
  .platform-brand__text { max-width: 112px; }
  .platform-menu-toggle { width: 40px; height: 40px; border-radius: 12px; }
  .learn-page { padding-top: 24px; }
  .course-grid { gap: 10px; }
  .course-card { padding: 16px; }
  .course-card__icon { width: 42px; height: 42px; font-size: 1.3rem; }
  .course-card h3 { margin-top: 13px; }
}
@media (prefers-reduced-motion: no-preference) {
  .learn-hero__character { animation: learn-hero-settle 520ms cubic-bezier(.23, 1, .32, 1) both; }
  .platform-menu-toggle, .platform-account, .button-primary, .button-secondary, .course-card--active { transition: transform 160ms cubic-bezier(.23, 1, .32, 1), filter 160ms cubic-bezier(.23, 1, .32, 1), background-color 160ms cubic-bezier(.23, 1, .32, 1); }
  .platform-menu-toggle:active, .platform-account:active, .button-primary:active, .button-secondary:active { transform: scale(.97); }
}
@keyframes learn-hero-settle {
  from { opacity: 0; transform: translateY(10px) scale(.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}


/* Q2-B public parent information layer.  This stylesheet is not loaded by app/index.html. */
.platform-shell__context { color: var(--platform-muted); font-size: .82rem; font-weight: 700; white-space: nowrap; }
.platform-nav__eyebrow { display: none; color: var(--platform-green); font-size: .76rem; font-weight: 800; letter-spacing: .06em; }
.public-page-kicker { display: inline-flex; align-items: center; gap: 8px; padding: 7px 12px; border: 1px solid #bfe2d5; border-radius: 999px; background: #f3fbf7; color: #2f7664; font-size: .82rem; font-weight: 800; }
.legal-page { background: linear-gradient(180deg, #fffdf8 0%, #f9f6ee 100%); }
.legal-page .legal-card { border: 1px solid var(--platform-line); border-radius: 26px; box-shadow: var(--platform-shadow); }
.article-library__trust { display: flex; align-items: flex-start; gap: 12px; max-width: 760px; margin: 8px auto 0; padding: 16px 18px; border: 1px solid #c9e5db; border-radius: 18px; background: #f3fbf7; color: #355c50; text-align: left; font-size: .9rem; line-height: 1.75; }
.article-library__trust strong { color: #255b4d; }
.q2b1-article-character { flex: none; align-self: flex-end; width: 76px; height: auto; margin: -38px -10px -27px 0; pointer-events: none; filter: drop-shadow(0 8px 8px rgba(54, 87, 73, .10)); }
@media (max-width: 860px) {
  .platform-shell__context { display: none; }
  .platform-nav__eyebrow { display: block; padding: 8px 12px 5px; }
  .article-library__trust { margin-top: 16px; padding: 14px 15px; }
  .q2b1-article-character { width: 62px; margin: -22px -8px -20px 0; }
}


/* Q2-C verified-child task context for the parent learning centre. */
.task-context { display: grid; grid-template-columns: minmax(190px, .52fr) minmax(0, 1fr); gap: 22px; margin-top: 24px; padding: 22px; background: linear-gradient(135deg, #f2faf6, #fffdf8); border-color: #b9dfd2; }
.task-context__child { padding: 16px; border-radius: 16px; background: #fff; }
.task-context__eyebrow { display: block; color: var(--platform-green); font-size: .78rem; font-weight: 800; letter-spacing: .06em; }
.task-context h2 { margin: 6px 0; color: var(--platform-ink); font-size: 1.32rem; line-height: 1.35; }
.task-context p { margin: 0; color: var(--platform-muted); font-size: .93rem; line-height: 1.65; }
.today-next-step { padding: 4px 0; }
.today-next-step h2 { margin-top: 5px; }
.task-context__actions { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 14px; }
.task-context__actions .button-primary, .task-context__actions .button-secondary { min-height: 44px; margin-top: 0; padding: 10px 14px; }
.task-context__manage { display: inline-flex; align-items: center; min-height: 44px; padding: 8px 4px; color: #416670; font-size: .9rem; font-weight: 800; text-decoration: underline; text-underline-offset: 3px; }
.task-context__note { grid-column: 1 / -1; padding-top: 13px; border-top: 1px solid #cce5dc; font-size: .84rem !important; }
@media (max-width: 680px) { .task-context { grid-template-columns: 1fr; gap: 14px; padding: 16px; } .task-context__actions { display: grid; grid-template-columns: 1fr; } .task-context__actions .button-primary, .task-context__actions .button-secondary, .task-context__manage { width: 100%; } .task-context__manage { justify-content: center; padding: 8px; } }


/* Q2-B.3 v2: W1 is a real, full-scene learning world. This stylesheet is not loaded by app/index.html. */
.island-map--world { margin: 34px 0 0; padding: 0; overflow: visible; border: 0; border-radius: 0; background: transparent; box-shadow: none; }
.island-map__heading { display: flex; align-items: flex-end; justify-content: space-between; gap: 18px; max-width: 960px; margin: 0 auto 14px; padding: 0 4px; }
.island-map__eyebrow { margin: 0 0 5px; color: var(--platform-green); font-size: .78rem; font-weight: 800; letter-spacing: .07em; }
.island-map__heading h2 { margin: 0; color: var(--platform-ink); font-size: clamp(1.5rem, 3vw, 2.15rem); line-height: 1.2; }
.island-map__heading p:not(.island-map__eyebrow) { max-width: 620px; margin: 8px 0 0; color: var(--platform-muted); font-size: .95rem; line-height: 1.65; }
.island-map__week-chip { flex: none; padding: 8px 11px; border: 1px solid #f0cf98; border-radius: 999px; background: #fffdf8; color: var(--platform-orange-dark); font-size: .78rem; font-weight: 800; white-space: nowrap; }
.island-map__scene { position: relative; width: min(100%, 720px); aspect-ratio: 3 / 4; margin: 0 auto; overflow: hidden; border: 0; border-radius: 34px; background: #79d3db; box-shadow: 0 22px 44px rgba(39, 84, 76, .18); isolation: isolate; }
.island-map__background { display: block; width: 100%; height: 100%; object-fit: cover; }
.island-map__station-layer { position: absolute; inset: 0; z-index: 3; }
.island-map__station { position: absolute; display: block; border-radius: 20px; color: #fff; text-decoration: none; cursor: pointer; }
.island-map__station::before { position: absolute; inset: 6%; border: 3px solid transparent; border-radius: 20px; background: rgba(255, 255, 255, 0); box-shadow: 0 0 0 0 rgba(255, 209, 126, 0); content: ''; transition: background-color 150ms ease, border-color 150ms ease, box-shadow 150ms ease; }
.island-map__station:hover::before, .island-map__station:focus-visible::before { border-color: rgba(255, 255, 255, .9); background: rgba(255, 247, 218, .16); box-shadow: 0 0 0 5px rgba(239, 155, 69, .35); }
.island-map__station:focus-visible { outline: 0; }
.island-map__station-pin { position: absolute; z-index: 1; top: 2px; right: 1px; display: grid; min-width: 72px; max-width: 98px; padding: 5px 7px 6px; border: 2px solid rgba(255, 255, 255, .94); border-radius: 16px 16px 16px 5px; background: #42957f; box-shadow: 0 4px 8px rgba(39, 66, 52, .22); color: #fff; font-weight: 900; text-align: center; line-height: 1.1; }
.island-map__station-day { display: block; font-size: .62rem; font-weight: 800; opacity: .92; white-space: nowrap; }
.island-map__station-topic { display: block; margin-top: 2px; font-size: .76rem; letter-spacing: -.035em; white-space: nowrap; }
.island-map__station--today .island-map__station-pin { background: #e78338; }
.island-map__station--done .island-map__station-pin { background: #369d73; }
.island-map__station--locked { cursor: default; }
.island-map__station--locked::before { border-color: rgba(236, 246, 244, .7); background: rgba(42, 76, 87, .20); box-shadow: none; }
.island-map__station--locked:hover::before { border-color: rgba(236, 246, 244, .7); background: rgba(42, 76, 87, .20); box-shadow: none; }
.island-map__station--locked .island-map__station-pin { background: #657f8b; box-shadow: 0 4px 8px rgba(39, 66, 52, .16); }
.island-map__station-sr { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
/* Hotspots follow the physical buildings in the portrait world image, not an external list. */
.island-map__station--d1 { left: 3%; top: 49%; width: 38%; height: 22%; }
.island-map__station--d2 { left: 5%; top: 28%; width: 40%; height: 23%; }
.island-map__station--d3 { left: 31%; top: 40%; width: 40%; height: 24%; }
.island-map__station--d4 { left: 55%; top: 20%; width: 40%; height: 22%; }
.island-map__station--d5 { left: 61%; top: 3%; width: 38%; height: 21%; }
.island-map__route-list { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.island-map__note { max-width: 720px; margin: 13px auto 0; color: #587168; font-size: .8rem; line-height: 1.55; text-align: center; }
@media (max-width: 680px) {
  .island-map--world { width: calc(100% + 32px); margin: 24px -16px 0; }
  .island-map__heading { display: block; padding: 0 20px; }
  .island-map__week-chip { display: inline-flex; margin-top: 11px; }
  .island-map__scene { width: 100%; border-radius: 0; box-shadow: 0 16px 32px rgba(39, 84, 76, .16); }
  .island-map__station-pin { min-width: 62px; max-width: 82px; padding: 4px 5px 5px; border-radius: 13px 13px 13px 4px; }
  .island-map__station-day { font-size: .55rem; }
  .island-map__station-topic { margin-top: 1px; font-size: .66rem; }
  .island-map__note { padding: 0 20px; text-align: left; }
}
@keyframes island-landmark-float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-4px); } }
@media (prefers-reduced-motion: no-preference) {
  .island-map__station::before, .island-map__station-pin { transition: transform 160ms cubic-bezier(.23, 1, .32, 1), background-color 160ms ease, box-shadow 160ms ease, border-color 160ms ease; }
  .island-map__station-pin { animation: island-landmark-float 4.8s ease-in-out infinite; }
  .island-map__station--d2 .island-map__station-pin { animation-delay: -.9s; }
  .island-map__station--d3 .island-map__station-pin { animation-delay: -1.8s; }
  .island-map__station--d4 .island-map__station-pin { animation-delay: -2.7s; }
  .island-map__station--d5 .island-map__station-pin { animation-delay: -3.6s; }
  .island-map__station:hover .island-map__station-pin, .island-map__station:focus-visible .island-map__station-pin { animation-play-state: paused; transform: translateY(-5px) scale(1.04); }
  .island-map__station:active .island-map__station-pin { transform: scale(.94); }
}
@media (prefers-reduced-motion: reduce) { .island-map__station-pin { animation: none; } }


/* Q2-B.4: the subject chooser is a learning archipelago, not a grid of course cards. */
.subject-world { margin: 0; }
.subject-world__scene { position: relative; width: min(100%, 760px); aspect-ratio: 3 / 4; margin: 0 auto; overflow: hidden; border-radius: 34px; background: #b8dded; box-shadow: 0 24px 48px rgba(47, 79, 91, .17); isolation: isolate; }
.subject-world__background { display: block; width: 100%; height: 100%; object-fit: cover; }
.subject-world__landmark-layer { position: absolute; inset: 0; z-index: 2; }
.subject-world__landmark { position: absolute; display: flex; flex-direction: column; align-items: flex-start; gap: 2px; max-width: 156px; padding: 8px 10px 9px; border: 2px solid rgba(255, 255, 255, .88); border-radius: 18px 18px 18px 5px; background: rgba(45, 98, 89, .88); box-shadow: 0 6px 14px rgba(30, 66, 63, .19); color: #fff; text-decoration: none; line-height: 1.15; }
.subject-world__landmark strong { font-size: .92rem; letter-spacing: -.02em; }
.subject-world__landmark > span:last-child { font-size: .66rem; font-weight: 700; line-height: 1.35; opacity: .94; }
.subject-world__daylight { padding-bottom: 2px; color: #fff0bb; font-size: .62rem; font-weight: 900; letter-spacing: .04em; }
.subject-world__landmark.is-open { background: linear-gradient(150deg, rgba(213, 117, 46, .96), rgba(237, 159, 69, .94)); box-shadow: 0 8px 18px rgba(178, 95, 26, .28); }
.subject-world__landmark.is-open:hover, .subject-world__landmark.is-open:focus-visible { outline: 0; filter: brightness(1.04); }
.subject-world__landmark.is-open:focus-visible { box-shadow: 0 0 0 5px rgba(255, 247, 201, .92), 0 8px 18px rgba(178, 95, 26, .28); }
.subject-world__landmark.is-planned { background: rgba(86, 111, 119, .82); opacity: .92; }
.subject-world__landmark--zh { left: 5%; top: 62%; }
.subject-world__landmark--en { left: 4%; top: 18%; }
.subject-world__landmark--think { left: 37%; top: 19%; }
.subject-world__landmark--gs { right: 4%; top: 39%; }
.subject-world__landmark--math { right: 5%; top: 68%; }
.subject-world__note { max-width: 760px; margin: 13px auto 0; color: #587168; font-size: .82rem; line-height: 1.55; text-align: center; }
@media (max-width: 680px) {
  .subject-world { width: calc(100% + 32px); margin-left: -16px; }
  .subject-world__scene { width: 100%; border-radius: 0; box-shadow: 0 17px 34px rgba(47, 79, 91, .15); }
  .subject-world__landmark { max-width: 128px; padding: 6px 7px 7px; border-radius: 14px 14px 14px 4px; }
  .subject-world__landmark strong { font-size: .75rem; }
  .subject-world__landmark > span:last-child { font-size: .57rem; }
  .subject-world__daylight { font-size: .52rem; }
  .subject-world__note { padding: 0 20px; text-align: left; }
}
@media (prefers-reduced-motion: no-preference) {
  .subject-world__landmark { animation: subject-island-float 5.2s ease-in-out infinite; transition: transform 160ms cubic-bezier(.23, 1, .32, 1), filter 160ms ease; }
  .subject-world__landmark--en { animation-delay: -.9s; }
  .subject-world__landmark--think { animation-delay: -1.8s; }
  .subject-world__landmark--gs { animation-delay: -2.7s; }
  .subject-world__landmark--math { animation-delay: -3.6s; }
  .subject-world__landmark.is-open:hover, .subject-world__landmark.is-open:focus-visible { animation-play-state: paused; transform: translateY(-4px) scale(1.03); }
  .subject-world__landmark.is-open:active { transform: scale(.97); }
}
@keyframes subject-island-float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-4px); } }
@media (prefers-reduced-motion: reduce) { .subject-world__landmark { animation: none; } }

/* Q2-B.4 corrective: the learning map is the first screen, not a scene inserted below a legacy hero. */
.learn-page--world { width: min(100%, 1120px); padding-top: 0; }
.learn-page--world .island-map--world { margin-top: 0; }
.learn-page--world .island-map__scene { min-height: min(880px, calc(100svh - 68px)); }
.island-map__scene-caption { position: absolute; z-index: 4; top: 18px; left: 18px; right: 18px; max-width: 300px; padding: 11px 13px; border: 1px solid rgba(255,255,255,.76); border-radius: 18px; background: rgba(255,253,246,.84); box-shadow: 0 8px 20px rgba(20,74,72,.15); color: #254d4c; backdrop-filter: blur(8px); pointer-events: none; }
.island-map__scene-caption p { margin: 0 0 3px; color: #39826d; font-size: .65rem; font-weight: 900; letter-spacing: .06em; }
.island-map__scene-caption h2 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: clamp(1.3rem, 3.5vw, 1.75rem); line-height: 1.2; }
.island-map__scene-caption > span { display: block; margin-top: 4px; color: #486f67; font-size: .76rem; line-height: 1.45; font-weight: 700; }
.learn-subject-world-root { margin-top: 0; padding: 34px 20px 48px; background: linear-gradient(180deg, #f4fbf7, #fffaf1); }
.learn-subject-world-root__caption { width: min(100%, 760px); margin: 0 auto 13px; color: #315c53; }
.learn-subject-world-root__caption p { margin: 0 0 4px; color: #3f8a73; font-size: .74rem; font-weight: 900; letter-spacing: .07em; }
.learn-subject-world-root__caption h2 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: clamp(1.45rem, 3vw, 2rem); line-height: 1.3; }
.learn-state-root { position: relative; display: grid; grid-template-columns: minmax(0, 1fr) minmax(230px, .48fr); gap: 24px; min-height: 440px; padding: 46px; overflow: hidden; border-radius: 0 0 34px 34px; background: linear-gradient(135deg, #d9f1e8, #fff2d6); color: #244a4b; }
.learn-state-root::before { content: '☁'; position: absolute; right: 8%; bottom: -8%; color: rgba(255,255,255,.6); font-size: 12rem; line-height: 1; }
.learn-state-root__copy, .learn-state-root__action { position: relative; z-index: 1; }
.learn-state-root__copy p, .learn-state-root__action small { display: block; margin: 0 0 8px; color: #3a846f; font-size: .75rem; font-weight: 900; letter-spacing: .07em; }
.learn-state-root__copy h1 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: clamp(2rem, 4vw, 3.2rem); line-height: 1.18; }
.learn-state-root__copy > span { display: block; max-width: 620px; margin-top: 14px; color: #426d68; line-height: 1.75; }
.learn-state-root__action { align-self: center; display: grid; gap: 9px; padding: 20px; border: 1px solid rgba(255,255,255,.85); border-radius: 22px; background: rgba(255,253,246,.76); box-shadow: 0 10px 24px rgba(36,88,77,.13); }
.learn-state-root__action strong { font-family: 'Noto Serif TC', serif; font-size: 1.25rem; }.learn-state-root__action > span { color: #4e706c; font-size: .9rem; line-height: 1.55; }
@media (max-width: 680px) {
  .learn-page--world { width: 100%; padding: 0 0 44px; }
  .learn-page--world .island-map--world { width: 100%; margin: 0; }
  .learn-page--world .island-map__scene { min-height: calc(100svh - 62px); border-radius: 0; }
  .island-map__scene-caption { top: 14px; left: 14px; right: 14px; max-width: 245px; padding: 8px 10px; border-radius: 14px; }
  .island-map__scene-caption p { font-size: .56rem; }.island-map__scene-caption h2 { font-size: 1.24rem; }.island-map__scene-caption > span { font-size: .65rem; }
  .learn-subject-world-root { padding: 30px 0 42px; }.learn-subject-world-root__caption { padding: 0 18px; }
  .learn-state-root { grid-template-columns: 1fr; min-height: calc(100svh - 62px); padding: 30px 20px; border-radius: 0; }.learn-state-root__action { align-self: end; }
}

/* UX-12 v2: a physically draggable, multi-island world track — never a selected-week background swap. */
.week-voyage { margin: 0; padding: 34px 0 24px; overflow: hidden; background: linear-gradient(180deg, #fcfffd 0%, #eef8f3 100%); color: #294f48; }
.week-voyage__heading { display: flex; align-items: end; justify-content: space-between; gap: 16px; width: min(100% - 40px, 920px); margin: 0 auto 15px; }
.week-voyage__heading p { margin: 0 0 4px; color: #3f8a73; font-size: .74rem; font-weight: 900; letter-spacing: .07em; }
.week-voyage__heading h2 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: clamp(1.45rem, 3vw, 2rem); line-height: 1.3; }
.week-voyage__heading > div:first-child > span { display: block; max-width: 590px; margin-top: 5px; color: #5b7770; font-size: .84rem; font-weight: 700; line-height: 1.55; }
.week-voyage__controls { display: flex; flex: none; gap: 8px; }
.week-voyage__control { display: inline-grid; width: 42px; height: 42px; place-items: center; padding: 0; border: 1px solid #b9dfd2; border-radius: 50%; background: #fffdf8; color: #286a5a; box-shadow: 0 6px 14px rgba(34,95,75,.12); font: 900 1.65rem/1 system-ui, sans-serif; cursor: pointer; transition: transform 160ms cubic-bezier(.23,1,.32,1), box-shadow 160ms ease, background-color 160ms ease; }
.week-voyage__control:hover, .week-voyage__control:focus-visible { background: #e7f6ef; box-shadow: 0 9px 16px rgba(34,95,75,.18); outline: 3px solid rgba(70,155,125,.28); outline-offset: 2px; }
.week-voyage__control:active { transform: scale(.97); }
.week-voyage__viewport { position: relative; width: min(100%, 980px); aspect-ratio: 16 / 10; margin: 0 auto; overflow: hidden; border-radius: 34px; background: #83ccd0; box-shadow: 0 19px 36px rgba(37,91,76,.18); isolation: isolate; touch-action: pan-y; user-select: none; cursor: grab; }
.week-voyage__viewport:active { cursor: grabbing; }
.week-voyage__track { position: relative; display: flex; width: max-content; height: 100%; background-color: #83ccd0; background-repeat: repeat-x; background-position: 0 50%; will-change: transform; }
/* The panorama and its tint each span the whole physical track. Individual weeks carry only
   transparent HTML landmarks, so crossing an HTML slot cannot create a background seam. */
.week-voyage__world-tint { position: absolute; inset: 0; z-index: 0; background: linear-gradient(180deg, rgba(17,82,88,.06), rgba(18,74,63,.08) 48%, rgba(12,60,62,.30)); pointer-events: none; }
.week-voyage__segment { position: relative; z-index: 1; width: min(100vw, 980px); height: 100%; flex: 0 0 min(100vw, 980px); overflow: hidden; background: transparent; }
.week-voyage__zone-art { display: none; }
.week-voyage__segment-meta { position: absolute; z-index: 3; top: 18px; left: 18px; max-width: min(66%, 440px); padding: 12px 15px; border: 1px solid rgba(255,255,255,.86); border-radius: 18px; background: rgba(255,253,246,.86); box-shadow: 0 9px 20px rgba(20,74,72,.16); color: #254d4c; backdrop-filter: blur(8px); pointer-events: none; }
.week-voyage__segment-meta p { margin: 0 0 3px; color: #39826d; font-size: .66rem; font-weight: 900; letter-spacing: .06em; }
.week-voyage__segment-meta h3 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: clamp(1.22rem, 2.8vw, 1.72rem); line-height: 1.2; }
.week-voyage__segment-meta > span { display: block; margin-top: 4px; color: #486f67; font-size: .76rem; font-weight: 700; line-height: 1.45; }
.week-voyage__day-layer { position: absolute; right: 4%; bottom: 9%; left: 4%; z-index: 4; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: clamp(7px, 1.5vw, 19px); align-items: end; pointer-events: none; }
.week-voyage__day { position: relative; display: grid; min-width: 0; justify-items: center; align-content: end; color: #fff; text-align: center; text-decoration: none; pointer-events: auto; }.week-voyage__day--d1 { transform: translateY(17px); }.week-voyage__day--d2 { transform: translateY(-35px); }.week-voyage__day--d3 { transform: translateY(4px); }.week-voyage__day--d4 { transform: translateY(-23px); }.week-voyage__day--d5 { transform: translateY(10px); }
.week-voyage__day-mascot { display: block; width: clamp(62px, 8.3vw, 94px); margin-bottom: -4px; filter: drop-shadow(0 8px 7px rgba(23,73,63,.24)); }.week-voyage__day-mascot img { display: block; width: 100%; height: auto; }
.week-voyage__day-copy { display: grid; width: 100%; min-width: 0; justify-items: center; padding: 3px 4px 4px; border: 1px solid rgba(255,255,255,.82); border-radius: 10px; background: rgba(255,253,246,.84); box-shadow: 0 3px 9px rgba(20,74,72,.13); color: #244d4b; line-height: 1.12; backdrop-filter: blur(4px); }.week-voyage__day-copy i { color: #3f7a69; font-size: .54rem; font-style: normal; font-weight: 900; line-height: 1.1; }.week-voyage__day-copy b { display: -webkit-box; overflow: hidden; color: #244d4b; font-size: .7rem; font-weight: 900; line-height: 1.2; -webkit-box-orient: vertical; -webkit-line-clamp: 2; }.week-voyage__day-copy small { display: none; }
.week-voyage__day.is-done .week-voyage__day-copy { background: rgba(243,255,248,.9); }.week-voyage__day.is-current .week-voyage__day-mascot { filter: drop-shadow(0 0 7px rgba(255,248,190,.98)) drop-shadow(0 8px 7px rgba(23,73,63,.24)); }.week-voyage__day.is-current .week-voyage__day-copy { border-color: rgba(255,239,174,.98); background: rgba(255,252,232,.9); }.week-voyage__day.is-locked, .week-voyage__day.is-preview { cursor: default; }.week-voyage__day.is-locked .week-voyage__day-mascot, .week-voyage__day.is-preview .week-voyage__day-mascot { filter: grayscale(1) saturate(0) opacity(.58) drop-shadow(0 5px 5px rgba(23,73,63,.18)); }.week-voyage__day.is-locked .week-voyage__day-copy, .week-voyage__day.is-preview .week-voyage__day-copy { background: rgba(242,246,244,.7); color: #647473; }.week-voyage__day.is-locked .week-voyage__day-copy i, .week-voyage__day.is-preview .week-voyage__day-copy i, .week-voyage__day.is-locked .week-voyage__day-copy b, .week-voyage__day.is-preview .week-voyage__day-copy b { color: #71807e; }.week-voyage__day.is-preview { opacity: .94; }
.week-voyage__day:is(a):hover .week-voyage__day-mascot, .week-voyage__day:is(a):focus-visible .week-voyage__day-mascot, .week-voyage__day.is-gated:hover .week-voyage__day-mascot, .week-voyage__day.is-gated:focus-visible .week-voyage__day-mascot { transform: translateY(-5px) scale(1.04); }.week-voyage__day:is(a):focus-visible, .week-voyage__day.is-gated:focus-visible { outline: 3px solid rgba(255,243,184,.92); outline-offset: 3px; }.week-voyage__day:is(a):active .week-voyage__day-mascot, .week-voyage__day.is-gated:active .week-voyage__day-mascot { transform: scale(.96); }
.week-voyage__gesture { position: absolute; z-index: 5; top: 18px; right: 18px; margin: 0; padding: 5px 8px; border-radius: 999px; background: rgba(18,73,73,.62); color: #fff; font-size: .6rem; font-weight: 800; letter-spacing: .03em; pointer-events: none; }.week-voyage__note { width: min(100% - 40px, 920px); margin: 10px auto 0; color: #54756d; font-size: .78rem; line-height: 1.6; }
@media (max-width: 680px) { .week-voyage { padding: 28px 0 20px; }.week-voyage__heading { align-items: start; width: calc(100% - 32px); }.week-voyage__heading h2 { font-size: 1.42rem; }.week-voyage__heading > div:first-child > span { font-size: .75rem; }.week-voyage__control { width: 36px; height: 36px; font-size: 1.38rem; }.week-voyage__viewport { width: 100%; aspect-ratio: 3 / 4; border-radius: 0; }.week-voyage__segment { width: 100vw; flex-basis: 100vw; }.week-voyage__segment-meta { top: 14px; left: 14px; max-width: 69%; padding: 9px 11px; border-radius: 14px; }.week-voyage__segment-meta p { font-size: .56rem; }.week-voyage__segment-meta h3 { font-size: 1.22rem; }.week-voyage__segment-meta > span { font-size: .65rem; }.week-voyage__day-layer { right: 10px; bottom: 11%; left: 10px; gap: 4px; }.week-voyage__day--d1 { transform: translateY(16px); }.week-voyage__day--d2 { transform: translateY(-31px); }.week-voyage__day--d3 { transform: translateY(3px); }.week-voyage__day--d4 { transform: translateY(-20px); }.week-voyage__day--d5 { transform: translateY(9px); }.week-voyage__day-mascot { width: clamp(49px, 14vw, 57px); margin-bottom: -3px; }.week-voyage__day-copy { padding: 3px 2px 4px; border-radius: 8px; }.week-voyage__day-copy i { font-size: .45rem; }.week-voyage__day-copy b { font-size: .59rem; line-height: 1.16; }.week-voyage__gesture { top: 15px; right: 12px; bottom: auto; font-size: .53rem; }.week-voyage__note { width: calc(100% - 32px); font-size: .72rem; } }
@media (prefers-reduced-motion: reduce) { .week-voyage__track { transition: none !important; }.week-voyage__day { transition: none; } }

/* LAUNCH-04: unopened Day 1 landmarks can explain the next step without opening content. */
.week-voyage__day.is-gated { appearance: none; padding: 0; border: 0; background: transparent; font: inherit; text-align: center; cursor: pointer; }
.week-voyage__day.is-gated .week-voyage__day-mascot { filter: grayscale(1) saturate(0) opacity(.58) drop-shadow(0 5px 5px rgba(23,73,63,.18)); }
.week-voyage__day.is-gated:hover .week-voyage__day-mascot, .week-voyage__day.is-gated:focus-visible .week-voyage__day-mascot { transform: translateY(-5px) scale(1.04); }.week-voyage__day.is-gated:focus-visible { outline: 3px solid rgba(255,243,184,.92); outline-offset: 3px; }
.week-voyage__day.is-gated:active .week-voyage__day-mascot { transform: scale(.96); }
.week-voyage__gate-dialog { display: grid; grid-template-columns: 1fr auto; gap: 14px; align-items: center; width: min(100% - 40px, 920px); margin: 12px auto 0; padding: 15px 17px; border: 1px solid #b9dfd2; border-radius: 20px; background: #f7fffa; box-shadow: 0 12px 24px rgba(33,98,79,.12); color: #294f48; }
.week-voyage__gate-dialog[hidden] { display: none; }
.week-voyage__gate-copy p { margin: 0 0 3px; color: #3f8a73; font-size: .68rem; font-weight: 900; letter-spacing: .06em; }
.week-voyage__gate-copy h3 { margin: 0; font-family: 'Noto Serif TC', serif; font-size: 1.08rem; }
.week-voyage__gate-copy > span { display: block; margin-top: 4px; color: #52736b; font-size: .78rem; font-weight: 700; line-height: 1.55; }
.week-voyage__gate-actions { display: flex; flex-wrap: wrap; gap: 8px; justify-content: end; align-items: center; }
.week-voyage__gate-actions .button-primary, .week-voyage__gate-actions .button-secondary { min-height: 40px; white-space: nowrap; }
@media (max-width: 680px) { .week-voyage__gate-dialog { grid-template-columns: 1fr; width: calc(100% - 32px); gap: 12px; padding: 13px 14px; border-radius: 16px; }.week-voyage__gate-actions { justify-content: stretch; }.week-voyage__gate-actions .button-primary, .week-voyage__gate-actions .button-secondary { flex: 1 1 100%; text-align: center; } }
@media (prefers-reduced-motion: reduce) { .week-voyage__day.is-gated { transition: none; } }