:root {
  --color-surface: #fafafa;
  --color-surface-alt: #f0f0f0;
  --color-surface-deep: #e3e2e2;
  --color-ink: #37312f;
  --color-ink-soft: #685e59;
  --color-ink-muted: #837772;
  --color-line: #d7d6d5;
  --color-primary: #c2531f;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #f2e3db;
  --color-accent: #197bb3;
  --color-accent-ink: #ffffff;
  --color-highlight: #d2e3ed;
  --color-focus: #0e78b3;
  --color-contrast-surface: #291b15;
  --color-contrast-ink: #e7e5e4;
  --color-contrast-line: #534743;
  --color-contrast-accent: #209adf;
  --overlay-scrim: linear-gradient(180deg, rgba(41, 27, 21, 0.35) 0%, rgba(41, 27, 21, 0.72) 55%, rgba(41, 27, 21, 0.92) 100%);
  --font-heading: "Source Han Sans SC", "Noto Sans SC", SimHei, "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 9.3px;
  --text-sm: 13.9px;
  --text-base: 17px;
  --text-lg: 25.5px;
  --text-xl: 38.2px;
  --text-2xl: 57.4px;
  --text-3xl: 86.1px;
  --text-4xl: 129.1px;
  --text-display: clamp(46px, 9.5vw, 122px);
  --text-figure: clamp(39px, 6.9vw, 88px);
  --weight-heading: 852;
  --weight-body: 400;
  --leading-body: 1.72;
  --leading-heading: 1.18;
  --tracking-heading: -0.016em;
  --radius-sm: 2px;
  --radius-md: 5px;
  --radius-lg: 8px;
  --radius-pill: 999px;
  --border-thin: 2px;
  --border-thick: 3px;
  --shadow-1: 4px 4px 0 #37312f;
  --shadow-2: 8px 8px 0 #37312f;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1200px;
  --measure: 67ch;
  --gutter: 24px;
  --section-y: 69px;
  --section-y-lg: 97px;
}

/* ============ reset ============ */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background: 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);
}

img, svg, video, canvas { display: block; max-width: 100%; }

button, input, select, textarea { font: inherit; color: inherit; }

table { border-collapse: collapse; }

[hidden] { display: none !important; }

:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
}

#main-content { scroll-margin-top: 150px; }

/* ============ 中文排版基座 ============ */
h1, h2, h3, h4, h5, h6 {
  margin: 0 0 var(--space-2);
  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 0 var(--space-3);
  max-width: var(--measure);
}

p:last-child { margin-bottom: 0; }

a {
  color: var(--color-accent);
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

a:hover { color: var(--color-primary); }

strong, b { font-weight: 700; }

::selection {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

/* ============ 布局容器 ============ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

.section--alt {
  background: var(--color-surface-alt);
  border-block: var(--border-thin) dashed var(--color-line);
}

.section--deep {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.section--deep h1,
.section--deep h2,
.section--deep h3,
.section--deep h4 { color: var(--color-contrast-ink); }

.section--deep a { color: var(--color-contrast-accent); }
.section--deep a:hover { color: var(--color-primary); }

.section--deep .lede,
.section--deep .meta,
.section--deep .stat-label { color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent); }

.section--deep .rule-dashed { border-top-color: var(--color-contrast-line); }

.section--cut {
  clip-path: polygon(0 26px, 100% 0, 100% calc(100% - 26px), 0 100%);
  padding-block: calc(var(--section-y-lg) + 26px);
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--space-3);
}

.col-2 { grid-column: span 2; }
.col-3 { grid-column: span 3; }
.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-9 { grid-column: span 9; }
.col-12 { grid-column: span 12; }

.stack { display: grid; gap: var(--space-3); align-content: start; }

.cluster {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
}

/* ============ 文字层级 ============ */
.display {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-display);
  line-height: 0.98;
  letter-spacing: var(--tracking-heading);
  margin: 0 0 var(--space-3);
}

.page-title {
  font-size: var(--text-3xl);
  line-height: 1.05;
  margin: 0 0 var(--space-3);
}

.section-title {
  font-size: var(--text-xl);
  margin: 0 0 var(--space-2);
}

.lede {
  font-size: var(--text-lg);
  line-height: 1.5;
  color: var(--color-ink-soft);
  max-width: 48ch;
  margin-bottom: var(--space-3);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.eyebrow::before {
  content: "";
  width: 24px;
  height: var(--border-thin);
  background: var(--color-primary);
  flex: none;
}

.meta {
  font-size: calc(var(--text-xs) * 1.24);
  line-height: 1.6;
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
  max-width: var(--measure);
}

.mono { font-family: var(--font-mono); letter-spacing: 0.04em; }

.num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

/* ============ 按钮 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 11px 22px;
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-decoration: none;
  box-shadow: var(--shadow-1);
  transition: transform 0.18s ease, box-shadow 0.18s ease, background-color 0.18s ease;
}

.btn:hover {
  color: var(--color-ink);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-2);
}

.btn:active { transform: translate(0, 0); box-shadow: var(--shadow-1); }

.btn--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn--primary:hover { color: var(--color-primary-ink); }

.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--accent:hover { color: var(--color-accent-ink); }

.btn--quiet {
  background: transparent;
  box-shadow: none;
  border-color: var(--color-line);
  color: var(--color-ink-soft);
}

.btn--quiet:hover {
  box-shadow: var(--shadow-1);
  background: var(--color-surface);
}

.section--deep .btn--quiet {
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}

.section--deep .btn--quiet:hover {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-accent);
}

/* ============ 标签与徽标 ============ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: var(--border-thin) solid currentColor;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
  white-space: nowrap;
}

.tag--primary {
  color: var(--color-primary);
  background: var(--color-primary-soft);
}

.tag--accent {
  color: var(--color-accent-ink);
  background: var(--color-accent);
  border-color: var(--color-accent);
}

.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 24px;
  height: 24px;
  padding: 0 6px;
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  font-weight: 700;
  letter-spacing: 0.04em;
}

/* ============ 面板与数据块 ============ */
.panel {
  padding: var(--space-3);
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-left: var(--border-thick) solid var(--color-primary);
  border-radius: var(--radius-sm);
}

.panel--outline {
  background: transparent;
  border-color: var(--color-line);
  border-left-color: var(--color-accent);
}

.panel--deep {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
  border-left-color: var(--color-contrast-accent);
}

.panel--deep .meta,
.panel--deep .stat-label { color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent); }

.stat { display: grid; gap: 6px; align-content: start; }

.stat-value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: var(--text-figure);
  line-height: 0.92;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--color-primary);
}

.panel--deep .stat-value,
.section--deep .stat-value { color: var(--color-contrast-accent); }

.stat-label {
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
  text-transform: uppercase;
  border-top: var(--border-thin) solid var(--color-line);
  padding-top: 6px;
}

.section--deep .stat-label,
.panel--deep .stat-label { border-top-color: var(--color-contrast-line); }

.entry {
  display: grid;
  gap: 6px;
  padding: var(--space-2) 0;
  border-top: var(--border-thin) dashed var(--color-line);
}

.entry-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-heading);
  margin: 0;
}

/* ============ 表格 ============ */
.data-table {
  width: 100%;
  font-size: var(--text-sm);
  text-align: left;
}

.data-table th {
  padding: 10px 12px;
  background: var(--color-surface-deep);
  border-bottom: var(--border-thin) solid var(--color-ink);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.14em;
  color: var(--color-ink);
  white-space: nowrap;
}

.data-table td {
  padding: 10px 12px;
  border-bottom: 1px dashed var(--color-line);
  font-variant-numeric: tabular-nums;
  color: var(--color-ink-soft);
}

.data-table tbody tr:hover { background: var(--color-highlight); }

.hit {
  background: var(--color-highlight);
  box-shadow: inset 0 -2px 0 var(--color-accent);
  color: var(--color-ink);
}

/* ============ 面包屑与分隔 ============ */
.breadcrumb {
  padding-block: var(--space-2);
  border-bottom: var(--border-thin) dashed var(--color-line);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  list-style: none;
  margin: 0;
  padding: 0;
}

.breadcrumb li { display: inline-flex; align-items: center; gap: var(--space-2); }

.breadcrumb li + li::before {
  content: "／";
  color: var(--color-line);
}

.breadcrumb a {
  color: var(--color-ink-muted);
  text-decoration: none;
}

.breadcrumb a:hover { color: var(--color-primary); }

.breadcrumb [aria-current="page"] { color: var(--color-ink); }

.rule-dashed {
  height: 0;
  margin: var(--space-4) 0;
  border: 0;
  border-top: var(--border-thin) dashed var(--color-line);
}

/* ============ 图片容器 ============ */
.image-slot {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-lg);
  background: var(--color-surface-deep);
}

.image-slot--wide { aspect-ratio: 21 / 9; }
.image-slot--tall { aspect-ratio: 3 / 4; }

.image-slot > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(0.42) contrast(1.06);
}

.image-slot-scrim {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: 6px;
  padding: var(--space-3);
  background: var(--overlay-scrim);
  color: var(--color-contrast-ink);
}

.image-slot-caption {
  margin: 0;
  max-width: 42ch;
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
}

/* ============ 滚动显现 ============ */
.reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  transition-delay: var(--reveal-delay, 0ms);
  will-change: opacity, transform;
}

.reveal.is-inview {
  opacity: 1;
  transform: none;
}

/* ============ 头部 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--color-surface);
  border-bottom: var(--border-thick) solid var(--color-ink);
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 10px;
  background: var(--color-accent);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
  pointer-events: none;
}

.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -120px;
  z-index: 90;
  padding: 10px 18px;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus { top: var(--space-2); color: var(--color-primary-ink); }

.scroll-progress {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 3px;
  z-index: 3;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
}

.header-rail {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.header-rail-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 38px;
  padding-block: 5px;
}

.rail-line {
  margin: 0;
  max-width: none;
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.16em;
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
}

.axis-switch {
  display: inline-flex;
  flex: none;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.axis-btn {
  appearance: none;
  border: 0;
  border-left: var(--border-thin) solid var(--color-contrast-line);
  background: transparent;
  color: var(--color-contrast-ink);
  padding: 4px 14px;
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.16em;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease;
}

.axis-btn:first-child { border-left: 0; }

.axis-btn:hover { background: color-mix(in srgb, var(--color-contrast-accent) 26%, transparent); }

.axis-btn[aria-pressed="true"] {
  background: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.header-bar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 74px;
  padding-block: var(--space-2);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  color: var(--color-ink);
  text-decoration: none;
  flex: none;
}

.brand::before {
  content: "";
  width: 10px;
  height: 30px;
  flex: none;
  background: var(--color-primary);
  clip-path: polygon(0 0, 100% 20%, 100% 100%, 0 80%);
}

.brand-mark {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1;
  letter-spacing: -0.02em;
}

.brand-text {
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.16em;
  color: var(--color-ink-muted);
}

.primary-nav { display: flex; }

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-link {
  display: inline-block;
  padding: 8px 11px;
  border-bottom: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--color-ink);
  text-decoration: none;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.nav-link:hover {
  color: var(--color-primary);
  background: var(--color-primary-soft);
  border-bottom-color: var(--color-primary);
}

.nav-link[aria-current="page"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-bottom-color: var(--color-ink);
}

.header-tools {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  flex: none;
}

.tool-btn,
.nav-toggle {
  appearance: none;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 9px 14px;
  background: var(--color-surface);
  color: var(--color-ink);
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-size: calc(var(--text-xs) * 1.24);
  font-weight: 700;
  letter-spacing: 0.14em;
  cursor: pointer;
  box-shadow: var(--shadow-1);
  transition: background-color 0.18s ease, color 0.18s ease, transform 0.18s ease;
}

.tool-btn:hover,
.nav-toggle:hover {
  background: var(--color-highlight);
  transform: translate(-1px, -1px);
}

.tool-btn[aria-expanded="true"],
.nav-toggle[aria-expanded="true"] {
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border-color: var(--color-accent);
}

.tool-btn-label,
.nav-toggle-label { display: inline-block; }

.nav-toggle { display: none; }

.nav-toggle-bars {
  position: relative;
  display: inline-block;
  width: 16px;
  height: 2px;
  background: currentColor;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
}

.nav-toggle-bars::before { top: -5px; }
.nav-toggle-bars::after { top: 5px; }

.search-panel {
  position: absolute;
  top: calc(100% + 2px);
  right: var(--gutter);
  z-index: 70;
  width: min(320px, calc(100vw - 2 * var(--gutter)));
  padding: var(--space-3);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-top: var(--border-thick) solid var(--color-contrast-accent);
  border-radius: var(--radius-sm);
  box-shadow: 8px 8px 0 color-mix(in srgb, var(--color-accent) 45%, transparent);
}

.search-panel-title {
  margin: 0;
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
}

.search-list {
  list-style: none;
  margin: var(--space-2) 0 0;
  padding: 0;
}

.search-list a {
  display: block;
  padding: 9px 0;
  border-top: 1px dashed var(--color-contrast-line);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  text-decoration: none;
}

.search-list a:hover { color: var(--color-contrast-accent); }

/* ============ 页脚 ============ */
.site-footer {
  margin-top: var(--section-y-lg);
  background: var(--color-surface-alt);
  color: var(--color-ink);
  border-top: var(--border-thin) dashed var(--color-line);
}

.footer-tick {
  height: 8px;
  background-image: repeating-linear-gradient(90deg, var(--color-line) 0 2px, transparent 2px 32px);
  border-bottom: var(--border-thin) dashed var(--color-line);
}

.footer-inner { padding-block: var(--space-6) var(--space-4); }

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: var(--space-6) var(--space-4);
}

.footer-logo {
  display: flex;
  flex-direction: column;
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1;
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  max-width: none;
}

.footer-logo span {
  margin-top: 6px;
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--color-ink-muted);
}

.footer-summary {
  margin: 0 0 var(--space-2);
  max-width: 42ch;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-ink-soft);
}

.footer-tagline {
  margin: 0;
  max-width: 42ch;
  font-size: calc(var(--text-xs) * 1.24);
  line-height: 1.7;
  color: var(--color-ink-muted);
}

.footer-heading {
  display: inline-block;
  margin: 0 0 var(--space-2);
  padding-bottom: 6px;
  border-bottom: var(--border-thin) solid var(--color-primary);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  font-weight: 400;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.footer-links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.footer-links a {
  display: inline-block;
  padding: 5px 0;
  border-bottom: var(--border-thin) solid transparent;
  color: var(--color-ink);
  font-size: var(--text-sm);
  text-decoration: none;
  transition: color 0.18s ease, border-color 0.18s ease;
}

.footer-links a:hover {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: calc(var(--text-xs) * 1.24);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
}

.footer-base p { margin: 0; max-width: none; }

.footer-contact { color: var(--color-ink-soft); }

.footer-legal { text-align: right; }

/* ============ 响应式 ============ */
@media (max-width: 1080px) {
  .header-rail-inner { flex-wrap: wrap; }

  .nav-toggle { display: inline-flex; }

  .primary-nav { order: 4; }

  .nav-list {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    z-index: 65;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: var(--space-3) var(--gutter) var(--space-4);
    background: var(--color-surface-alt);
    border-top: var(--border-thick) solid var(--color-ink);
    border-bottom: var(--border-thick) solid var(--color-ink);
  }

  [data-nav][data-open="true"] .nav-list { display: flex; }

  .nav-link {
    display: block;
    padding: 14px 4px;
    border-bottom: 1px dashed var(--color-line);
    border-radius: 0;
    font-size: var(--text-base);
  }

  .nav-link[aria-current="page"] {
    background: var(--color-primary);
    color: var(--color-primary-ink);
    border-bottom-color: var(--color-primary);
    padding-inline: 12px;
  }
}

@media (max-width: 900px) {
  .col-2, .col-3, .col-4, .col-5 { grid-column: span 6; }
  .col-6, .col-7, .col-8, .col-9 { grid-column: span 12; }

  .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-4); }

  .footer-legal { text-align: left; }
}

@media (max-width: 620px) {
  :root { --gutter: 18px; }

  .display { line-height: 1.02; }
  .page-title { font-size: var(--text-2xl); }
  .section-title { font-size: var(--text-lg); }
  .lede { font-size: var(--text-base); }

  .col-2, .col-3, .col-4, .col-5, .col-6, .col-7, .col-8, .col-9, .col-12 {
    grid-column: span 12;
  }

  .header-rail-inner { gap: var(--space-2); padding-block: var(--space-1); }
  .rail-line { letter-spacing: 0.08em; font-size: var(--text-xs); }
  .axis-btn { padding: 4px 10px; letter-spacing: 0.08em; }

  .header-bar { min-height: 64px; }
  .brand-text { display: none; }

  .footer-grid { grid-template-columns: 1fr; gap: var(--space-4); }
  .search-panel { right: var(--gutter); left: var(--gutter); width: auto; }
}

/* ============ 无障碍与动效降级 ============ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .btn:hover,
  .tool-btn:hover,
  .nav-toggle:hover { transform: none; }
}