:root {
  color-scheme: light dark;
  font-family: Inter, "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  --bg: #fffaf3;
  --surface: #ffffff;
  --text: #2b2118;
  --muted: #6f6258;
  --line: #eadfd2;
  --accent: #b45309;
  --accent-soft: #ffedd5;
  --shadow: 0 18px 55px rgb(73 41 13 / 9%);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--text); line-height: 1.75; }
a { color: var(--accent); text-underline-offset: 0.2em; }
.hero { background: linear-gradient(145deg, #7c2d12, #b45309 58%, #d97706); color: white; }
.hero__content { width: min(960px, calc(100% - 32px)); margin: 0 auto; padding: 64px 0 54px; }
.eyebrow { margin: 0 0 8px; font-weight: 700; letter-spacing: 0.08em; opacity: 0.82; }
h1 { margin: 0; font-size: clamp(2.4rem, 7vw, 4.4rem); line-height: 1.1; }
.lead { max-width: 720px; margin: 20px 0 28px; font-size: 1.08rem; opacity: 0.94; }
.meta { display: flex; flex-wrap: wrap; gap: 12px; margin: 0; }
.meta div { min-width: 200px; padding: 10px 14px; border: 1px solid rgb(255 255 255 / 24%); border-radius: 12px; background: rgb(255 255 255 / 10%); }
.meta dt { font-size: 0.76rem; opacity: 0.72; }
.meta dd { margin: 1px 0 0; font-weight: 650; }
.meta a { color: white; }
main { display: grid; grid-template-columns: 210px minmax(0, 710px); gap: 42px; width: min(1000px, calc(100% - 32px)); margin: 38px auto 70px; }
.toc { position: sticky; top: 24px; align-self: start; display: grid; gap: 7px; padding: 18px; border: 1px solid var(--line); border-radius: 16px; background: var(--surface); box-shadow: var(--shadow); }
.toc strong { margin-bottom: 5px; }
.toc a { color: var(--muted); text-decoration: none; font-size: 0.92rem; }
.toc a:hover, .toc a:focus-visible { color: var(--accent); }
article { min-width: 0; }
section { padding: 28px 0; border-bottom: 1px solid var(--line); scroll-margin-top: 24px; }
section:first-child { padding-top: 0; }
h2 { margin: 0 0 13px; font-size: 1.42rem; line-height: 1.35; }
h3 { margin: 0 0 6px; font-size: 1rem; }
p, ul, ol { margin: 0 0 13px; }
li + li { margin-top: 7px; }
.summary { padding: 22px; border: 1px solid #fed7aa; border-radius: 18px; background: var(--accent-soft); }
.summary ul { margin-bottom: 0; padding-left: 1.3em; }
.cards { display: grid; gap: 12px; }
.cards > div { padding: 17px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface); }
.cards p { color: var(--muted); }
footer { padding: 28px 16px 40px; color: var(--muted); text-align: center; }

@media (max-width: 760px) {
  .hero__content { padding: 44px 0 38px; }
  main { display: block; margin-top: 22px; }
  .toc { position: static; margin-bottom: 26px; grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .toc strong { grid-column: 1 / -1; }
  section { padding: 24px 0; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #17120e;
    --surface: #211a15;
    --text: #f6eadf;
    --muted: #c7b7aa;
    --line: #44352a;
    --accent: #fb923c;
    --accent-soft: #3c2414;
    --shadow: none;
  }
  .hero { background: linear-gradient(145deg, #431407, #7c2d12 60%, #9a3412); }
  .summary { border-color: #713815; }
}

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