:root {
  color-scheme: light;
  --paper: #fff7ed;
  --ink: #171717;
  --muted: #64615d;
  --line: #e7d8c9;
  --surface: #fffdf8;
  --red: #be123c;
  --green: #0f766e;
  --shadow: 0 18px 56px rgba(23, 23, 23, 0.11);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
}

a {
  color: inherit;
}

.site-shell {
  width: min(920px, calc(100% - 28px));
  margin: 0 auto;
}

.topbar {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 950;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  background: #fff;
  color: var(--red);
  box-shadow: 0 8px 20px rgba(23, 23, 23, 0.08);
}

.topbar nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  color: var(--muted);
  font-weight: 800;
}

.topbar nav a {
  text-decoration: none;
}

.hero {
  padding: 52px 0 28px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--green);
  font-size: 0.76rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  max-width: 820px;
  margin: 0;
  font-size: clamp(2.6rem, 7vw, 5.4rem);
  line-height: 0.98;
  letter-spacing: 0;
}

.intro {
  max-width: 700px;
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 1.12rem;
  line-height: 1.65;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.primary-action,
.secondary-action {
  min-height: 48px;
  border-radius: 8px;
  padding: 0 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  font-weight: 900;
}

.primary-action {
  background: var(--red);
  color: #fffaf2;
}

.secondary-action {
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--ink);
}

.article-card,
.phrase-card,
.note-card,
.toc {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 10px 26px rgba(23, 23, 23, 0.06);
}

.toc {
  padding: 18px;
  margin: 18px 0 26px;
}

.toc a {
  display: inline-flex;
  margin: 6px 14px 6px 0;
  color: var(--green);
  font-weight: 850;
  text-decoration: none;
}

.article-card {
  padding: 28px;
  margin: 18px 0;
}

.article-card h2 {
  margin: 0 0 14px;
  font-size: clamp(1.55rem, 4vw, 2.4rem);
  line-height: 1.08;
}

.article-card p,
.article-card li,
.note-card p {
  color: var(--muted);
  line-height: 1.68;
}

.phrase-grid {
  display: grid;
  gap: 10px;
}

.phrase-card {
  padding: 18px;
}

.phrase-card .zh {
  margin: 0;
  color: #050505;
  font-size: clamp(1.65rem, 7vw, 2.7rem);
  line-height: 1.15;
  font-weight: 950;
}

.phrase-card .en {
  margin: 10px 0 0;
  color: #2d2c2a;
  font-weight: 850;
}

.phrase-card .use {
  margin: 6px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.note-card {
  padding: 20px;
  margin: 18px 0;
  background: #f8fafc;
}

.article-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.article-list a {
  min-height: 138px;
  display: grid;
  align-content: start;
  gap: 8px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
  background: var(--surface);
  color: var(--ink);
  text-decoration: none;
}

.article-list strong {
  font-size: 1.12rem;
}

.article-list small {
  color: var(--muted);
  line-height: 1.5;
}

.site-footer {
  margin: 48px 0 26px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  line-height: 1.6;
}

.site-footer a {
  color: #0f766e;
  font-weight: 760;
}

@media (max-width: 680px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    padding: 16px 0;
  }

  .article-list {
    grid-template-columns: 1fr;
  }

  .article-card {
    padding: 20px;
  }
}