:root {
  --ink: #1c211d;
  --forest: #173b31;
  --paper: #fbf8f1;
  --cream: #eee4d4;
  --accent: #b26c32;
  --accent-soft: #e7cdb5;
  --line: rgba(28, 33, 29, 0.15);
  --serif: "Noto Serif TC", Georgia, serif;
  --sans: "Noto Sans TC", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); line-height: 1.7; }
a { color: inherit; text-decoration: none; }
.skip-link { position: fixed; top: -5rem; left: 1rem; z-index: 100; padding: .8rem 1rem; background: white; }
.skip-link:focus { top: 1rem; }

.course-header { height: 76px; padding: 0 clamp(1.2rem, 5vw, 5rem); display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--line); background: rgba(251,248,241,.95); }
.course-brand { display: flex; align-items: center; gap: .75rem; }
.course-brand-mark { width: 42px; height: 42px; display: grid; place-items: center; border: 1px solid var(--forest); border-radius: 50%; color: var(--forest); font: 700 1.2rem var(--serif); }
.course-brand-name { display: grid; line-height: 1.1; }
.course-brand-name strong { font: 700 1rem var(--serif); letter-spacing: .12em; }
.course-brand-name small { margin-top: .3rem; font-size: .56rem; letter-spacing: .24em; }
.course-header-nav { display: flex; align-items: center; gap: 1.6rem; font-size: .8rem; font-weight: 600; letter-spacing: .06em; }
.course-header-nav a:last-child { padding: .55rem 1rem; border: 1px solid var(--forest); border-radius: 999px; }

.course-hero { position: relative; min-height: 600px; padding: 5.5rem clamp(1.2rem, 7vw, 8rem); display: grid; grid-template-columns: 1.15fr .85fr; align-items: center; gap: clamp(3rem, 8vw, 8rem); overflow: hidden; background: var(--forest); color: white; }
.course-hero::before { content: ""; position: absolute; width: 620px; height: 620px; right: -230px; top: -300px; border: 1px solid rgba(255,255,255,.12); border-radius: 50%; box-shadow: 0 0 0 70px rgba(255,255,255,.025), 0 0 0 150px rgba(255,255,255,.018); }
.breadcrumbs { margin: 0 0 2rem; color: rgba(255,255,255,.55); font-size: .72rem; letter-spacing: .08em; }
.breadcrumbs a:hover { color: white; }
.course-kicker { margin: 0 0 1rem; color: var(--accent-soft); font-size: .68rem; font-weight: 700; letter-spacing: .25em; }
.course-hero h1 { margin: 0; font: 700 clamp(3rem, 7vw, 6.2rem)/1.05 var(--serif); letter-spacing: .04em; }
.course-hero h1 span { display: block; margin-top: 1rem; color: rgba(255,255,255,.5); font: 500 clamp(.85rem, 1.5vw, 1.1rem) var(--sans); letter-spacing: .24em; }
.course-lead { max-width: 640px; margin: 2rem 0 0; color: rgba(255,255,255,.72); font-size: 1.02rem; }
.course-symbol { position: relative; aspect-ratio: 1; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.24); border-radius: 50%; color: var(--accent-soft); background: radial-gradient(circle at 35% 30%, rgba(255,255,255,.12), transparent 42%); font: 700 clamp(4rem, 9vw, 8rem)/1 var(--serif); letter-spacing: -.06em; }
.course-symbol::after { content: attr(data-index); position: absolute; right: 8%; bottom: 10%; width: 60px; height: 60px; display: grid; place-items: center; border-radius: 50%; color: var(--forest); background: var(--accent-soft); font: 700 .72rem var(--sans); letter-spacing: .1em; }

.course-overview, .course-levels, .course-fit, .course-enroll { padding: 7rem clamp(1.2rem, 7vw, 8rem); }
.section-heading { max-width: 1200px; margin: 0 auto 3.5rem; display: grid; grid-template-columns: .8fr 1.2fr; gap: 4rem; align-items: end; }
.section-label { margin: 0 0 1rem; color: var(--accent); font-size: .68rem; font-weight: 700; letter-spacing: .24em; }
.section-heading h2, .course-fit h2, .course-enroll h2 { margin: 0; font: 700 clamp(2rem, 4vw, 3.8rem)/1.28 var(--serif); }
.section-heading > p { margin: 0; max-width: 620px; color: rgba(28,33,29,.62); }
.topic-grid { max-width: 1200px; margin: auto; display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.topic-card { min-height: 210px; padding: 2rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: rgba(255,255,255,.28); }
.topic-card span { display: block; margin-bottom: 2rem; color: var(--accent); font-size: .7rem; font-weight: 700; letter-spacing: .16em; }
.topic-card h3 { margin: 0 0 .7rem; font: 700 1.3rem var(--serif); }
.topic-card p { margin: 0; color: rgba(28,33,29,.58); font-size: .88rem; }

.course-levels { background: #eee6d9; }
.level-grid { max-width: 1200px; margin: auto; display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.level-card { padding: 2.2rem; background: var(--paper); border-top: 5px solid var(--accent); }
.level-number { color: var(--accent); font-size: .7rem; font-weight: 700; letter-spacing: .15em; }
.level-card h3 { margin: .8rem 0 .3rem; font: 700 1.7rem var(--serif); }
.level-meta { margin: 0 0 1.7rem; color: rgba(28,33,29,.5); font-size: .75rem; }
.level-card ul { margin: 0; padding: 0; list-style: none; }
.level-card li { position: relative; padding: .75rem 0 .75rem 1.2rem; border-top: 1px solid var(--line); font-size: .88rem; }
.level-card li::before { content: ""; position: absolute; left: 0; top: 1.45rem; width: 5px; height: 5px; border-radius: 50%; background: var(--accent); }
.official-note { max-width: 1200px; margin: 2rem auto 0; color: rgba(28,33,29,.54); font-size: .76rem; }
.official-note a { border-bottom: 1px solid currentColor; }

.course-fit { display: grid; grid-template-columns: .8fr 1.2fr; gap: clamp(3rem, 8vw, 8rem); background: var(--paper); }
.fit-intro p:last-child { max-width: 480px; color: rgba(28,33,29,.6); }
.fit-list { border-top: 1px solid var(--line); }
.fit-item { padding: 1.4rem 0; display: grid; grid-template-columns: 60px 1fr; gap: 1rem; border-bottom: 1px solid var(--line); }
.fit-item span { color: var(--accent); font-size: .72rem; font-weight: 700; }
.fit-item p { margin: 0; }

.course-enroll { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 2rem 3rem; color: white; background: var(--forest); }
.course-enroll p:not(.section-label) { max-width: 700px; color: rgba(255,255,255,.65); }
.enroll-actions { display: flex; gap: .8rem; flex-wrap: wrap; }
.course-button { min-height: 50px; padding: .75rem 1.3rem; display: inline-flex; align-items: center; justify-content: center; border-radius: 999px; font-size: .82rem; font-weight: 700; letter-spacing: .06em; }
.course-button-primary { color: var(--forest); background: var(--accent-soft); }
.course-button-line { color: white; background: #06c755; }
.course-button-secondary { border: 1px solid rgba(255,255,255,.45); }
.course-source { margin-top: 1.5rem; font-size: .72rem; }
.course-source a { color: var(--accent-soft); border-bottom: 1px solid currentColor; }
.course-socials { grid-column: 1 / -1; display: flex; gap: 1.5rem; font-size: .78rem; font-weight: 700; }
.course-socials a { color: var(--accent-soft); border-bottom: 1px solid rgba(255,255,255,.3); }

.course-footer { padding: 2.5rem clamp(1.2rem, 5vw, 5rem); display: flex; align-items: center; justify-content: space-between; gap: 2rem; color: rgba(255,255,255,.56); background: #102720; font-size: .72rem; }
.course-footer a { color: white; }
.course-footer-links { display: flex; flex-wrap: wrap; gap: .7rem 1.4rem; }

@media (max-width: 900px) {
  .course-hero { grid-template-columns: 1fr; }
  .course-symbol { width: min(420px, 82vw); justify-self: center; }
  .section-heading, .course-fit { grid-template-columns: 1fr; gap: 1.5rem; }
  .topic-grid { grid-template-columns: repeat(2, 1fr); }
  .level-grid { grid-template-columns: 1fr; }
  .course-enroll { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .course-header { height: 66px; padding: 0 1rem; }
  .course-brand-name small, .course-header-nav a:first-child { display: none; }
  .course-hero { padding: 4.5rem 1.2rem; min-height: auto; }
  .course-overview, .course-levels, .course-fit, .course-enroll { padding: 5rem 1.2rem; }
  .topic-grid { grid-template-columns: 1fr; }
  .course-footer { align-items: flex-start; flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }