:root {
  --paper: #f5f1e8;
  --surface: #fffdf8;
  --ink: #18211e;
  --muted: #5b6863;
  --line: #d7d0c2;
  --green: #0f6655;
  --green-soft: #dcece5;
  --shadow: 0 16px 45px rgba(36, 43, 39, 0.09);
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }

body {
  min-width: 320px;
  margin: 0;
  background:
    radial-gradient(circle at 8% 0%, rgba(15, 102, 85, 0.1), transparent 32rem),
    var(--paper);
}

a { color: inherit; }

.shell {
  width: min(1080px, calc(100% - 32px));
  margin: 0 auto;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 72px;
  color: var(--muted);
  font-size: 0.9rem;
}

.brand {
  color: var(--ink);
  font-family: ui-serif, "Songti SC", STSong, Georgia, serif;
  font-size: 1.15rem;
  text-decoration: none;
}

main { padding: clamp(42px, 9vw, 110px) 0 90px; }

.eyebrow {
  margin: 0 0 14px;
  color: var(--green);
  font-size: 0.78rem;
  font-weight: 750;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

h1 {
  max-width: 15ch;
  margin: 0;
  font: 730 clamp(3rem, 9vw, 7rem) / 1.06 ui-serif, "Songti SC", STSong, Georgia, serif;
  letter-spacing: -0.04em;
}

.intro {
  max-width: 670px;
  margin: 26px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 2.2vw, 1.2rem);
  line-height: 1.75;
}

.course-list {
  display: grid;
  gap: 18px;
  margin-top: clamp(48px, 8vw, 88px);
}

.course-card {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(220px, 0.7fr);
  gap: clamp(24px, 5vw, 64px);
  padding: clamp(28px, 6vw, 64px);
  border: 1px solid rgba(15, 102, 85, 0.22);
  border-radius: 24px;
  background: linear-gradient(135deg, var(--surface), #edf4ed);
  box-shadow: var(--shadow);
  text-decoration: none;
  transition: transform 150ms ease, border-color 150ms ease;
}

.course-card:hover,
.course-card:focus-visible {
  border-color: var(--green);
  transform: translateY(-3px);
  outline: 3px solid rgba(15, 102, 85, 0.12);
}

.course-card h2 {
  margin: 0 0 14px;
  font: 700 clamp(1.8rem, 4vw, 3.2rem) / 1.2 ui-serif, "Songti SC", STSong, Georgia, serif;
  letter-spacing: -0.03em;
}

.course-card p {
  max-width: 58ch;
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.course-meta {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: flex-end;
  gap: 24px;
  color: var(--green);
  font-size: 0.9rem;
  text-align: right;
}

.count {
  font: 650 clamp(2.5rem, 7vw, 5rem) / 1 ui-serif, Georgia, serif;
  letter-spacing: -0.06em;
}

footer {
  display: flex;
  justify-content: space-between;
  padding: 22px 0 38px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.8rem;
}

@media (max-width: 680px) {
  .shell { width: min(100% - 20px, 1080px); }
  .course-card { grid-template-columns: 1fr; }
  .course-meta { align-items: flex-start; text-align: left; }
  footer { flex-direction: column; gap: 8px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}