* { box-sizing: border-box; }
:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --surface: #ffffff;
  --text: #16171a;
  --muted: #666a73;
  --line: #dfe2e8;
  --accent: #4057d6;
  --accent-soft: #edf0ff;
  --max: 1160px;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #0b0c0f;
    --surface: #15161a;
    --text: #f3f4f6;
    --muted: #a5a8b0;
    --line: #2f3138;
    --accent: #8795ff;
    --accent-soft: #252a49;
  }
}
html { min-width: 320px; background: var(--bg); scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font: 400 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
}
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; border-radius: 6px; }
.shell { width: min(calc(100% - 40px), var(--max)); margin: 0 auto; }
.site-header { min-height: 78px; display: flex; align-items: center; justify-content: space-between; gap: 28px; }
.brand { font-size: 1.05rem; font-weight: 700; letter-spacing: -.02em; }
.brand span { color: var(--accent); }
.site-nav { display: flex; align-items: center; gap: clamp(18px, 3vw, 34px); }
.site-nav a { color: var(--muted); font-size: .94rem; }
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--text); }
.app-link { padding: 9px 14px; border: 1px solid var(--line); border-radius: 999px; background: var(--surface); }
.hero { min-height: calc(100vh - 78px); padding: clamp(74px, 12vh, 140px) 0 80px; display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(300px, .8fr); gap: clamp(54px, 8vw, 110px); align-items: center; }
.kicker { margin: 0 0 16px; color: var(--accent); font-weight: 650; letter-spacing: .04em; }
h1 { margin: 0; max-width: 780px; font-size: clamp(3.2rem, 7vw, 6.8rem); line-height: .98; letter-spacing: -.065em; font-weight: 620; }
.hero-copy { margin: 28px 0 0; max-width: 650px; color: var(--muted); font-size: clamp(1.05rem, 1.6vw, 1.24rem); }
.hero-actions { margin-top: 34px; display: flex; flex-wrap: wrap; gap: 12px; }
.button { min-height: 48px; padding: 0 20px; border: 1px solid var(--line); border-radius: 13px; display: inline-flex; align-items: center; justify-content: center; background: var(--surface); font-weight: 620; }
.button.primary { border-color: var(--accent); background: var(--accent); color: #fff; }
.index-card { border: 1px solid var(--line); border-radius: 24px; overflow: hidden; background: var(--surface); box-shadow: 0 28px 80px rgba(20, 22, 31, .08); }
.index-label { padding: 18px 22px; border-bottom: 1px solid var(--line); color: var(--muted); font-size: .88rem; }
.index-row { min-height: 98px; padding: 20px 22px; display: grid; grid-template-columns: 42px 1fr auto; gap: 16px; align-items: center; border-bottom: 1px solid var(--line); }
.index-row:last-child { border-bottom: 0; }
.index-number { color: var(--accent); font-variant-numeric: tabular-nums; }
.index-row strong { display: block; font-size: 1.02rem; }
.index-row small { display: block; margin-top: 3px; color: var(--muted); font-size: .85rem; }
.index-arrow { color: var(--muted); font-size: 1.35rem; }
.section { padding: 92px 0; border-top: 1px solid var(--line); }
.section-heading { display: grid; grid-template-columns: .7fr 1.3fr; gap: 50px; }
.section-heading h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.8rem); line-height: 1.05; letter-spacing: -.045em; }
.section-heading p { margin: 0; color: var(--muted); font-size: 1.05rem; }
.page-hero { padding: 90px 0 66px; }
.page-hero h1 { max-width: 900px; font-size: clamp(2.8rem, 6vw, 5.6rem); }
.page-hero p { max-width: 700px; margin: 24px 0 0; color: var(--muted); font-size: 1.08rem; }
.content-grid { padding: 20px 0 100px; display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 70px; }
.side-note { color: var(--muted); font-size: .9rem; }
.content section { padding: 0 0 46px; margin-bottom: 46px; border-bottom: 1px solid var(--line); }
.content section:last-child { border-bottom: 0; }
.content h2 { margin: 0 0 20px; font-size: 1.55rem; }
.content h3 { margin: 24px 0 6px; font-size: 1.06rem; }
.content p { margin: 0; color: var(--muted); }
.tag-list { display: flex; flex-wrap: wrap; gap: 10px; }
.tag { padding: 8px 12px; border-radius: 999px; background: var(--accent-soft); color: var(--accent); font-size: .88rem; }
.project-list { padding: 18px 0 100px; border-top: 1px solid var(--line); }
.project-row { min-height: 142px; display: grid; grid-template-columns: 130px minmax(0, 1fr) auto; gap: 28px; align-items: center; border-bottom: 1px solid var(--line); }
.project-row time { color: var(--muted); font-size: .9rem; }
.project-row h2 { margin: 0; font-size: clamp(1.35rem, 3vw, 2rem); }
.project-row p { margin: 8px 0 0; max-width: 650px; color: var(--muted); }
.status { padding: 7px 11px; border-radius: 999px; background: var(--surface); border: 1px solid var(--line); color: var(--muted); font-size: .82rem; }
.site-footer { padding: 34px 0 48px; border-top: 1px solid var(--line); display: flex; justify-content: space-between; gap: 20px; color: var(--muted); font-size: .88rem; }
@media (max-width: 760px) {
  .shell { width: min(calc(100% - 30px), var(--max)); }
  .site-header { min-height: 68px; align-items: flex-start; padding: 18px 0; }
  .site-nav { gap: 12px; flex-wrap: wrap; justify-content: flex-end; }
  .site-nav a { font-size: .84rem; }
  .hero { min-height: auto; padding: 70px 0; grid-template-columns: 1fr; }
  h1 { font-size: clamp(3rem, 15vw, 5rem); }
  .section-heading, .content-grid { grid-template-columns: 1fr; gap: 24px; }
  .project-row { grid-template-columns: 1fr auto; gap: 10px 18px; padding: 24px 0; }
  .project-row time { grid-column: 1 / -1; }
  .site-footer { flex-direction: column; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }