/* ============================================================
   买球主站 · /assets/site.css
   共享外壳：设计变量 / 重置 / 头部 / 页脚 / 通用组件
   ============================================================ */

:root {
  --color-surface: #fafafa;
  --color-surface-alt: #f1f1f1;
  --color-surface-deep: #e4e5e5;
  --color-ink: #3f4b48;
  --color-ink-soft: #61706c;
  --color-ink-muted: #778883;
  --color-line: #d8dada;
  --color-primary: #2f836d;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #dee9e6;
  --color-accent: #177f91;
  --color-accent-ink: #ffffff;
  --color-highlight: #d1e4e7;
  --color-focus: #0e7d90;
  --color-contrast-surface: #172420;
  --color-contrast-ink: #e4e7e6;
  --color-contrast-line: #444f4c;
  --color-contrast-accent: #23c1dc;
  --overlay-scrim: linear-gradient(180deg, rgba(23, 36, 32, 0.35) 0%, rgba(23, 36, 32, 0.72) 55%, rgba(23, 36, 32, 0.92) 100%);
  --font-heading: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-body: "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 12.2px;
  --text-sm: 14.6px;
  --text-base: 16px;
  --text-lg: 19.2px;
  --text-xl: 23.0px;
  --text-2xl: 27.6px;
  --text-3xl: 33.2px;
  --text-4xl: 39.8px;
  --text-display: clamp(40px, 8.1vw, 104px);
  --text-figure: clamp(33px, 5.9vw, 75px);
  --weight-heading: 772;
  --weight-body: 400;
  --leading-body: 1.67;
  --leading-heading: 1.28;
  --tracking-heading: 0.006em;
  --radius-sm: 14px;
  --radius-md: 16px;
  --radius-lg: 17px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 6px 18px rgba(63, 75, 72, 0.08);
  --shadow-2: 0 18px 44px rgba(63, 75, 72, 0.14);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1200px;
  --measure: 72ch;
  --gutter: 32px;
  --section-y: 71px;
  --section-y-lg: 99px;
}

/* ---------- 1. Reset & 中文排版基准 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-underline-offset: 3px;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-accent); }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: 0; padding: 0; }
img, svg, video { display: block; max-width: 100%; height: auto; }
figure { margin: 0; }
::selection { background: var(--color-highlight); color: var(--color-ink); }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 3px; border-radius: var(--radius-sm); }
#main-content { display: block; scroll-margin-top: 112px; }

/* ---------- 2. 工具类 ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--space-3);
}
.mono { font-family: var(--font-mono); }
.meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  color: var(--color-ink-muted);
}
.text-soft { color: var(--color-ink-soft); }
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 3. 跳转链接与滚动进度 ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: var(--space-3);
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-accent);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-2);
  transition: top 160ms linear;
}
.skip-link:focus { top: var(--space-2); color: var(--color-contrast-accent); }

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 120ms linear;
  pointer-events: none;
  z-index: 190;
}

/* ---------- 4. 悬浮胶囊头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  padding: var(--space-2) var(--space-3) var(--space-1);
  background: color-mix(in srgb, var(--color-surface) 84%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  transition: padding 200ms linear, background 200ms linear;
}
.site-header[data-scrolled="true"] {
  padding-top: var(--space-1);
  padding-bottom: var(--space-1);
  background: color-mix(in srgb, var(--color-surface) 96%, transparent);
}

.header-inner {
  position: relative;
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
}

.brand-island {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 6px 18px 6px 6px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-alt);
  color: var(--color-ink);
  box-shadow: var(--shadow-1);
  transition: background 180ms linear;
}
.brand-island:hover { background: var(--color-primary-soft); color: var(--color-ink); }

.brand-mark {
  flex: 0 0 auto;
  width: 36px;
  height: 36px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-pill);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-accent);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.02em;
}
.brand-text { display: grid; gap: 1px; line-height: 1.2; }
.brand-name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  letter-spacing: 0.02em;
}
.brand-tag {
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.04em;
}

.nav-island {
  display: flex;
  align-items: center;
  padding: 6px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-alt);
  box-shadow: var(--shadow-1);
}
.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav-item { display: flex; }
.nav-link {
  display: inline-block;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  white-space: nowrap;
  transition: background 180ms linear, color 180ms linear;
}
.nav-link:hover { background: var(--color-primary-soft); color: var(--color-ink); }
.nav-link[aria-current="page"] {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-accent);
  font-weight: 600;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  box-shadow: var(--shadow-1);
}
.nav-toggle:hover { color: var(--color-contrast-accent); }
.nav-toggle-icon { display: grid; gap: 5px; width: 16px; }
.nav-toggle-icon span {
  display: block;
  height: 1.5px;
  border-radius: var(--radius-pill);
  background: currentColor;
  transition: transform 180ms linear;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:first-child {
  transform: translateY(3.25px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:last-child {
  transform: translateY(-3.25px) rotate(-45deg);
}
.nav-toggle-label { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.08em; }

.header-rail {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  width: 100%;
  max-width: var(--container);
  margin: var(--space-1) auto 0;
  max-height: 30px;
  overflow: hidden;
  opacity: 1;
  transition: max-height 220ms linear, opacity 160ms linear, margin 220ms linear;
}
.site-header[data-scrolled="true"] .header-rail {
  max-height: 0;
  margin-top: 0;
  opacity: 0;
}
.mono-tag {
  flex: 0 0 auto;
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  background: var(--color-highlight);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
}
.rail-tick { flex: 0 0 auto; width: 16px; height: 2px; border-radius: var(--radius-pill); background: var(--color-primary); }
.rail-text {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.03em;
}

/* ---------- 5. 阶梯式页脚 ---------- */
.site-footer {
  margin-top: var(--section-y-lg);
  padding-bottom: var(--space-6);
}
.footer-tier { color: var(--color-primary-ink); }
.footer-tier--index {
  margin-inline: var(--space-3);
  padding-block: var(--space-8) var(--space-6);
  border-radius: var(--radius-lg);
  background: var(--color-primary);
  color: var(--color-primary-ink);
}
.footer-tier--legal {
  margin-inline: calc(var(--space-3) + var(--space-4));
  margin-top: var(--space-2);
  padding-block: var(--space-6);
  border-radius: var(--radius-lg);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.footer-tier-inner { display: grid; gap: var(--gutter); }
.footer-tier--index .footer-tier-inner { grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); align-items: start; }
.footer-tier--legal .footer-tier-inner { grid-template-columns: minmax(0, 1fr); gap: var(--space-3); }

.footer-brand { display: grid; gap: var(--space-1); justify-items: start; }
.footer-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--color-primary-ink) 18%, transparent);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  margin-bottom: var(--space-1);
}
.footer-brand-name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  color: var(--color-primary-ink);
}
.footer-brand-tag { font-size: var(--text-sm); color: var(--color-primary-ink); opacity: 0.86; }
.footer-brand-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-primary-ink);
  opacity: 0.7;
}

.footer-label {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-primary-ink);
  opacity: 0.68;
  margin-bottom: var(--space-2);
}
.footer-label--inverse { color: var(--color-contrast-accent); opacity: 0.9; }

.footer-index-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-1) var(--space-3);
}
.footer-link {
  display: inline-block;
  padding: 3px 0;
  font-size: var(--text-sm);
  color: var(--color-primary-ink);
  opacity: 0.88;
  transition: opacity 160ms linear, color 160ms linear;
}
.footer-link:hover { opacity: 1; color: var(--color-primary-ink); text-decoration: underline; }
.footer-link--inverse { color: var(--color-contrast-ink); opacity: 0.84; }
.footer-link--inverse:hover { color: var(--color-contrast-accent); opacity: 1; }

.footer-legal-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  align-items: center;
}
.footer-legal-item { display: flex; align-items: center; font-size: var(--text-sm); }
.footer-mono {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-contrast-ink);
  opacity: 0.76;
}
.footer-note {
  padding-top: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  color: var(--color-contrast-accent);
  opacity: 0.82;
}

/* ---------- 6. 章节骨架 ---------- */
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--tight { padding-block: var(--space-6); }
.section-head {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  max-width: var(--measure);
  margin-bottom: var(--space-4);
}
.section-title { font-size: var(--text-3xl); }
.section-note {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

/* ---------- 7. Bento 网格 ---------- */
.bento {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
  align-items: start;
}
.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: 1 / -1; }

.breath {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding-block: var(--space-8);
}
.breath-line {
  max-width: var(--measure);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-xl);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}

/* ---------- 8. 卡片 ---------- */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  background: var(--color-surface-alt);
  box-shadow: var(--shadow-1);
}
.card--soft { background: var(--color-primary-soft); box-shadow: none; }
.card--deep { background: var(--color-surface-deep); box-shadow: none; }
.card--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
  box-shadow: var(--shadow-2);
}
.card--contrast {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  box-shadow: var(--shadow-2);
}
.card-title { font-size: var(--text-lg); }
.card-text { font-size: var(--text-sm); color: var(--color-ink-soft); }
.card-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  color: var(--color-ink-muted);
}
.card--accent .card-title,
.card--accent .card-text,
.card--accent .card-meta { color: var(--color-accent-ink); }
.card--accent .card-text { opacity: 0.86; }
.card--accent .card-meta { opacity: 0.78; }
.card--contrast .card-title { color: var(--color-contrast-ink); }
.card--contrast .card-text { color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent); }
.card--contrast .card-meta { color: var(--color-contrast-accent); }

.card-corner-tag {
  position: absolute;
  top: var(--space-2);
  right: var(--space-2);
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  background: var(--color-highlight);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
}
.card--accent .card-corner-tag {
  background: color-mix(in srgb, var(--color-accent-ink) 22%, transparent);
  color: var(--color-accent-ink);
}
.card--contrast .card-corner-tag {
  background: color-mix(in srgb, var(--color-contrast-accent) 20%, transparent);
  color: var(--color-contrast-accent);
}

.side-version {
  position: absolute;
  top: var(--space-3);
  right: var(--space-1);
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}
.card--contrast .side-version { color: var(--color-contrast-accent); }

.side-note {
  position: relative;
  padding-left: var(--space-3);
  color: var(--color-ink-soft);
}
.side-note::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.15em;
  bottom: 0.15em;
  width: 3px;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
  transform-origin: top center;
  transform: scaleY(1);
  transition: transform 300ms linear;
}
.side-note--accent::before { background: var(--color-accent); }
.card--contrast .side-note { color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent); }
.card--contrast .side-note::before { background: var(--color-contrast-accent); }
.js-ready .side-note[data-reveal]::before { transform: scaleY(0); }
.js-ready .side-note[data-reveal].is-revealed::before { transform: scaleY(1); }

/* ---------- 9. 标签与可复制角标 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: var(--radius-pill);
  background: var(--color-primary-soft);
  color: var(--color-ink);
  font-size: var(--text-xs);
  line-height: 1.4;
}
.tag--mono { font-family: var(--font-mono); letter-spacing: 0.03em; color: var(--color-accent); background: var(--color-highlight); }
.tag-row { display: flex; flex-wrap: wrap; gap: var(--space-1); }

.tag-version {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: var(--radius-pill);
  background: var(--color-highlight);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  transition: background 160ms linear, color 160ms linear;
}
.tag-version:hover { background: color-mix(in srgb, var(--color-highlight) 72%, var(--color-accent)); }
.tag-version[data-copied="true"] {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}
.tag-version[data-copied="true"]::after { content: "已标注"; margin-left: 6px; opacity: 0.86; }
.card--contrast .tag-version {
  background: color-mix(in srgb, var(--color-contrast-accent) 20%, transparent);
  color: var(--color-contrast-accent);
}
.card--contrast .tag-version[data-copied="true"] {
  background: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

/* ---------- 10. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 12px 24px;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-sm);
  letter-spacing: 0.03em;
  transition: background 180ms linear, color 180ms linear, transform 180ms linear;
}
.btn--primary { background: var(--color-contrast-surface); color: var(--color-contrast-accent); }
.btn--primary:hover { background: color-mix(in srgb, var(--color-contrast-surface) 84%, var(--color-accent)); color: var(--color-contrast-accent); }
.btn--accent { background: var(--color-accent); color: var(--color-accent-ink); }
.btn--accent:hover { background: color-mix(in srgb, var(--color-accent) 84%, var(--color-contrast-surface)); color: var(--color-accent-ink); }
.btn--ghost { background: var(--color-primary-soft); color: var(--color-ink); }
.btn--ghost:hover { background: var(--color-highlight); color: var(--color-accent); }
.btn:active { transform: translateY(1px); }

/* ---------- 11. 面包屑 ---------- */
.breadcrumb { padding-top: var(--space-3); }
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  color: var(--color-ink-muted);
}
.breadcrumb-item { display: flex; align-items: center; gap: var(--space-1); }
.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  color: var(--color-line);
}
.breadcrumb-item a { color: var(--color-ink-soft); }
.breadcrumb-item a:hover { color: var(--color-accent); }

/* ---------- 12. 主题筛选 ---------- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  margin-bottom: var(--space-4);
}
.filter-btn {
  padding: 9px 18px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-alt);
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  transition: background 180ms linear, color 180ms linear;
}
.filter-btn:hover { background: var(--color-primary-soft); color: var(--color-ink); }
.filter-btn[aria-pressed="true"] { background: var(--color-accent); color: var(--color-accent-ink); }
.filter-count {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  margin-left: var(--space-1);
}
[data-filter-item] { transition: opacity 180ms linear, transform 180ms linear; }
[data-filter-item][data-filtered="out"] { opacity: 0.55; transform: scale(0.986); }

/* ---------- 13. 图片容器与展签 ---------- */
.figure {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--color-surface-deep);
}
.figure > img { width: 100%; height: 100%; object-fit: cover; }
.figure--wide > img { aspect-ratio: 16 / 9; }
.figure--tall > img { aspect-ratio: 4 / 5; }
.figure--square > img { aspect-ratio: 1 / 1; }
.figure--overlay::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}
.figure-caption {
  position: absolute;
  left: var(--space-2);
  bottom: var(--space-2);
  z-index: 2;
  max-width: calc(100% - var(--space-4));
  padding: 5px 11px;
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, var(--color-contrast-surface) 74%, transparent);
  color: var(--color-contrast-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
}
.figure-note {
  margin-top: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.03em;
  color: var(--color-ink-muted);
}
.media-placeholder {
  display: grid;
  place-items: center;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  background: var(--color-surface-deep);
  color: var(--color-ink-muted);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}

/* ---------- 14. 正文与列表 ---------- */
.prose {
  max-width: var(--measure);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--color-ink-soft);
}
.prose > * + * { margin-top: var(--space-3); }
.prose h2 { font-size: var(--text-2xl); color: var(--color-ink); }
.prose h3 { font-size: var(--text-xl); color: var(--color-ink); }
.prose strong { color: var(--color-ink); font-weight: 600; }
.prose a { text-decoration: underline; text-decoration-thickness: 1px; }
.prose ul li,
.prose ol li { position: relative; padding-left: var(--space-3); }
.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
}
.prose ol { counter-reset: proselist; }
.prose ol li { counter-increment: proselist; }
.prose ol li::before {
  content: counter(proselist, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-primary);
}
.prose--on-contrast { color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent); }
.prose--on-contrast h2,
.prose--on-contrast h3,
.prose--on-contrast strong { color: var(--color-contrast-ink); }
.prose--on-contrast ul li::before { background: var(--color-contrast-accent); }
.prose--on-contrast ol li::before { color: var(--color-contrast-accent); }

.step-list { display: grid; gap: var(--space-2); counter-reset: step; }
.step {
  position: relative;
  padding-left: 64px;
  min-height: 40px;
  font-size: var(--text-base);
  color: var(--color-ink-soft);
}
.step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  width: 44px;
  height: 40px;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
}
.card--contrast .step { color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent); }
.card--contrast .step::before { background: var(--color-contrast-accent); color: var(--color-contrast-surface); }

/* ---------- 15. 对照表 ---------- */
.compare-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}
.compare-table caption {
  text-align: left;
  padding-bottom: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
.compare-table th,
.compare-table td {
  text-align: left;
  padding: 14px var(--space-2);
  vertical-align: top;
}
.compare-table thead th {
  position: sticky;
  top: 88px;
  z-index: 3;
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}
.compare-table tbody tr:nth-child(even) { background: var(--color-surface-alt); }
.compare-table tbody th {
  position: relative;
  padding-left: var(--space-3);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-base);
  color: var(--color-ink);
}
.compare-table tbody th::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 3px;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
}

/* ---------- 16. 侧边目录 ---------- */
.layout-aside {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 268px;
  gap: var(--gutter);
  align-items: start;
}
.layout-aside--left { grid-template-columns: 268px minmax(0, 1fr); }
.toc {
  position: sticky;
  top: 104px;
  display: grid;
  gap: var(--space-1);
  padding: var(--space-3);
  border-radius: var(--radius-lg);
  background: var(--color-surface-alt);
}
.toc-title {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  color: var(--color-ink-muted);
}
.toc-list { display: grid; gap: 2px; }
.toc-link {
  position: relative;
  display: block;
  padding: 7px 12px;
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  transition: background 160ms linear, color 160ms linear;
}
.toc-link:hover { background: var(--color-primary-soft); color: var(--color-ink); }
.toc-link.is-active { color: var(--color-ink); font-weight: 600; }
.toc-link.is-active::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 3px;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
}

/* ---------- 17. 数字条 ---------- */
.stat { display: grid; gap: var(--space-1); }
.stat-figure {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-figure);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--color-ink);
}
.stat-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  color: var(--color-ink-muted);
}
.card--contrast .stat-figure { color: var(--color-contrast-accent); }
.card--contrast .stat-label { color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent); }

/* ---------- 18. 显现动效 ---------- */
.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 300ms linear, transform 300ms linear;
}
.js-ready [data-reveal].is-revealed { opacity: 1; transform: none; }

/* ---------- 19. 响应式 ---------- */
@media (max-width: 1080px) {
  .bento { gap: var(--space-3); }
  .span-3 { grid-column: span 6; }
  .span-4 { grid-column: span 6; }
  .span-5 { grid-column: span 6; }
  .span-7 { grid-column: 1 / -1; }
  .span-8 { grid-column: 1 / -1; }
  .span-9 { grid-column: 1 / -1; }
  .layout-aside,
  .layout-aside--left { grid-template-columns: minmax(0, 1fr); }
  .toc { position: static; }
  .footer-tier--index .footer-tier-inner { grid-template-columns: minmax(0, 1fr); }
  .footer-tier--legal { margin-inline: var(--space-3); }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }
  .header-rail { display: none; }
  .nav-island {
    position: absolute;
    top: calc(100% + 12px);
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-2);
    border-radius: var(--radius-lg);
    background: var(--color-surface);
    box-shadow: var(--shadow-2);
  }
  .nav-island[data-open="true"] { display: flex; }
  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }
  .nav-item { display: block; }
  .nav-link { display: block; padding: 12px 16px; border-radius: var(--radius-sm); font-size: var(--text-base); }
  .footer-index-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .compare-table thead th { position: static; }
}

@media (max-width: 640px) {
  .site-header { padding-inline: var(--space-2); }
  .brand-tag { display: none; }
  .bento { grid-template-columns: minmax(0, 1fr); gap: var(--space-2); }
  .span-3, .span-4, .span-5, .span-6, .span-7, .span-8, .span-9, .span-12 { grid-column: 1 / -1; }
  .card { padding: var(--space-3); }
  .section { padding-block: var(--space-6); }
  .section--lg { padding-block: var(--space-8); }
  .footer-tier--index,
  .footer-tier--legal { margin-inline: var(--space-2); }
  .footer-tier--index { padding-block: var(--space-6) var(--space-4); }
  .footer-tier--legal { padding-block: var(--space-4); }
  .footer-index-list { grid-template-columns: minmax(0, 1fr); }
  .footer-legal-list { flex-direction: column; align-items: flex-start; gap: var(--space-1); }
  .stat-figure { letter-spacing: -0.01em; }
}

/* ---------- 20. 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    transition-duration: 1ms !important;
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
  }
  .js-ready [data-reveal] { opacity: 1; transform: none; }
  .js-ready .side-note[data-reveal]::before { transform: scaleY(1); }
  [data-filter-item][data-filtered="out"] { transform: none; }
  .scroll-progress { transition: none; }
}