/* ============================================================
   开运体育 · /assets/site.css
   双色海报 / 色块反转分区 / 夜间档案库
   ============================================================ */

:root {
  --color-surface: #f9f9f9;
  --color-surface-alt: #efefef;
  --color-surface-deep: #e1e1e1;
  --color-ink: #2d3134;
  --color-ink-soft: #596064;
  --color-ink-muted: #757c80;
  --color-line: #d4d5d6;
  --color-primary: #197bb3;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #dae7ef;
  --color-accent: #e3220c;
  --color-accent-ink: #ffffff;
  --color-highlight: #f5d2ce;
  --color-focus: #e01700;
  --color-contrast-surface: #0e161b;
  --color-contrast-ink: #e4e6e7;
  --color-contrast-line: #3d4448;
  --color-contrast-accent: #f3321c;
  --overlay-scrim: linear-gradient(180deg, rgba(14, 22, 27, 0.35) 0%, rgba(14, 22, 27, 0.72) 55%, rgba(14, 22, 27, 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: 11.0px;
  --text-sm: 14.7px;
  --text-base: 17px;
  --text-lg: 22.7px;
  --text-xl: 30.2px;
  --text-2xl: 40.3px;
  --text-3xl: 53.7px;
  --text-4xl: 71.5px;
  --text-display: clamp(49px, 10.2vw, 130px);
  --text-figure: clamp(41px, 7.3vw, 94px);
  --weight-heading: 883;
  --weight-body: 400;
  --leading-body: 1.76;
  --leading-heading: 1.23;
  --tracking-heading: -0.021em;
  --radius-sm: 1px;
  --radius-md: 2px;
  --radius-lg: 2px;
  --radius-pill: 2px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1140px;
  --measure: 66ch;
  --gutter: 16px;
  --section-y: 91px;
  --section-y-lg: 127px;
}

/* ------------------------------------------------------------
   1. 重置
   ------------------------------------------------------------ */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  background-color: var(--color-surface);
}

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;
  text-rendering: optimizeLegibility;
}

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);
  text-wrap: balance;
}

p { margin: 0 0 var(--space-2); }
p:last-child { margin-bottom: 0; }

ul, ol {
  margin: 0 0 var(--space-2);
  padding-inline-start: 1.25em;
}
li { margin-bottom: 4px; }

a {
  color: var(--color-primary);
  text-decoration-thickness: var(--border-thin);
  text-underline-offset: 3px;
}

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

button, input, select, textarea {
  font: inherit;
  color: inherit;
  margin: 0;
}

button { cursor: pointer; }

hr { border: 0; margin: 0; }

[hidden] { display: none !important; }

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

:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

[id] { scroll-margin-top: 96px; }

/* ------------------------------------------------------------
   2. 容器
   ------------------------------------------------------------ */
.shell {
  width: 100%;
  max-width: calc(var(--container) + var(--space-3) * 2);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

/* ------------------------------------------------------------
   3. 跳过链接
   ------------------------------------------------------------ */
.skip-link {
  position: absolute;
  top: 0;
  left: var(--space-3);
  z-index: 130;
  transform: translateY(-140%);
  display: inline-block;
  padding: 10px 20px;
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  text-decoration: none;
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  transition: transform 160ms cubic-bezier(0.2, 0.7, 0.2, 1);
}
.skip-link:focus {
  transform: translateY(0);
  color: var(--color-accent-ink);
}

/* ------------------------------------------------------------
   4. 头部
   ------------------------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-surface);
}

.header-ticker {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  max-height: 56px;
  overflow: hidden;
  transition: max-height 220ms cubic-bezier(0.2, 0.7, 0.2, 1),
              opacity 160ms linear;
}

.site-header.is-scrolled .header-ticker {
  max-height: 0;
  opacity: 0;
  border-bottom-color: transparent;
}

.header-ticker__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-1) var(--space-4);
  min-height: 40px;
  padding-block: 7px;
}

.ticker-note {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  line-height: 1.7;
  color: var(--color-contrast-ink);
}

.ticker-note--quiet {
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.ticker-sep { color: var(--color-contrast-line); }

.ticker-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  background-color: var(--color-contrast-accent);
  border-radius: var(--radius-sm);
  animation: tickerPulse 2.6s steps(1, end) infinite;
}

@keyframes tickerPulse {
  0%, 58% { opacity: 1; }
  59%, 100% { opacity: 0.22; }
}

.header-bar {
  position: relative;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.header-bar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  min-height: 78px;
  padding-block: 10px;
  transition: min-height 220ms cubic-bezier(0.2, 0.7, 0.2, 1),
              padding 220ms cubic-bezier(0.2, 0.7, 0.2, 1);
}

.site-header.is-scrolled .header-bar__inner {
  min-height: 62px;
  padding-block: 6px;
}

/* 品牌浮岛 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 16px 6px 6px;
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--color-ink);
  transition: background-color 160ms linear;
}
.brand:hover { color: var(--color-ink); }
.brand:focus-visible { outline-offset: 3px; }

.brand__mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  flex: none;
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: 20px;
  line-height: 1;
  border-radius: var(--radius-sm);
  transition: background-color 160ms linear;
}
.brand:hover .brand__mark { background-color: var(--color-accent); }

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand__name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-heading);
}

.brand__sub {
  font-size: var(--text-xs);
  letter-spacing: 0.22em;
  color: var(--color-ink-muted);
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  border: 0;
  border-radius: var(--radius-md);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  transition: background-color 160ms linear, color 160ms linear;
}
.nav-toggle[aria-expanded="true"] {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.nav-toggle__bars {
  display: grid;
  gap: 4px;
}

.nav-toggle__bar {
  display: block;
  width: 15px;
  height: 2px;
  background-color: currentColor;
}

/* 栏目浮岛 */
.site-nav { position: relative; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 4px;
  list-style: none;
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
}
.site-nav__list > li { margin: 0; }

.site-nav__link {
  display: block;
  padding: 9px 15px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  line-height: 1.5;
  white-space: nowrap;
  text-decoration: none;
  color: var(--color-ink-soft);
  border-radius: var(--radius-sm);
  transition: background-color 160ms linear, color 160ms linear;
}
.site-nav__link:hover {
  background-color: var(--color-surface-deep);
  color: var(--color-ink);
}
.site-nav__link[aria-current="page"] {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}

/* ------------------------------------------------------------
   5. 页脚
   ------------------------------------------------------------ */
.site-footer {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thin) solid var(--color-contrast-line);
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1) var(--space-4);
  padding-block: var(--space-4);
  font-size: var(--text-sm);
  line-height: 1.9;
}

.site-footer__brand {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.site-footer__mark {
  display: inline-block;
  width: 10px;
  height: 10px;
  background-color: var(--color-contrast-accent);
  border-radius: var(--radius-sm);
}

.site-footer__nav {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-3);
  margin-inline-start: auto;
}

.site-footer__link {
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
  text-decoration: none;
  border-bottom: var(--border-thin) solid transparent;
  transition: color 150ms linear, border-color 150ms linear;
}
.site-footer__link:hover {
  color: var(--color-contrast-ink);
  border-bottom-color: var(--color-contrast-accent);
}
.site-footer__link:focus-visible { outline-offset: 3px; }

.site-footer__meta,
.site-footer__icp,
.site-footer__copy {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.07em;
  color: color-mix(in srgb, var(--color-contrast-ink) 64%, transparent);
}

.site-footer__icp { color: var(--color-contrast-ink); }

/* ------------------------------------------------------------
   6. 区块与色块反转
   ------------------------------------------------------------ */
.section {
  padding-block: var(--section-y);
}
.section--lg {
  padding-block: var(--section-y-lg);
}

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

.section--primary .lede,
.section--accent .lede,
.section--contrast .lede {
  color: inherit;
  opacity: 0.86;
}
.section--primary .prose,
.section--accent .prose,
.section--contrast .prose { color: inherit; }

.section--primary .eyebrow,
.section--accent .eyebrow { color: color-mix(in srgb, currentColor 72%, transparent); }
.section--contrast .eyebrow { color: color-mix(in srgb, var(--color-contrast-ink) 60%, transparent); }

.rule {
  height: var(--border-thin);
  background-color: var(--color-line);
  border: 0;
  margin: 0;
}
.section--primary .rule { background-color: color-mix(in srgb, var(--color-primary-ink) 34%, transparent); }
.section--accent .rule  { background-color: color-mix(in srgb, var(--color-accent-ink) 34%, transparent); }
.section--contrast .rule { background-color: var(--color-contrast-line); }
.section--deep .rule { background-color: color-mix(in srgb, var(--color-ink) 14%, transparent); }

/* ------------------------------------------------------------
   7. 栅格与工具
   ------------------------------------------------------------ */
.grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: var(--gutter);
}

.span-1 { grid-column: span 1; }
.span-2 { grid-column: span 2; }
.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }

.stack {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.measure { max-width: var(--measure); }

/* ------------------------------------------------------------
   8. 文字层级
   ------------------------------------------------------------ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.22em;
  line-height: 1.8;
  color: var(--color-ink-muted);
}

.section-title {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-3xl);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

.lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.62;
  color: var(--color-ink-soft);
}

.prose {
  max-width: var(--measure);
  color: var(--color-ink-soft);
}

.prose--legal p,
.prose--legal li {
  font-size: var(--text-sm);
  line-height: 1.9;
  color: var(--color-ink-muted);
}

.prose--legal strong { color: var(--color-ink); }

/* 超大章节编号 */
.chapter-num {
  display: block;
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: var(--text-figure);
  line-height: 0.84;
  letter-spacing: -0.05em;
  font-variant-numeric: tabular-nums;
  color: var(--color-primary);
}
.chapter-num--sm { font-size: var(--text-4xl); }
.section--primary .chapter-num { color: var(--color-primary-ink); }
.section--accent .chapter-num  { color: var(--color-accent-ink); }
.section--contrast .chapter-num{ color: var(--color-contrast-accent); }
.section--deep .chapter-num    { color: var(--color-ink); }

/* ------------------------------------------------------------
   9. 按钮 / 标签 / 面板 / 面包屑
   ------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 24px;
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: background-color 160ms linear, color 160ms linear, border-color 160ms linear;
}
.btn:hover {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
}

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

.btn--ghost {
  background-color: transparent;
  color: var(--color-ink);
  border-color: var(--color-line);
}
.btn--ghost:hover {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-surface);
}

.btn--block { width: 100%; }

.section--contrast .btn--ghost,
.section--primary .btn--ghost {
  color: inherit;
  border-color: color-mix(in srgb, currentColor 45%, transparent);
}
.section--contrast .btn--ghost:hover,
.section--primary .btn--ghost:hover {
  background-color: var(--color-contrast-ink);
  color: var(--color-contrast-surface);
  border-color: var(--color-contrast-ink);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  background-color: var(--color-primary-soft);
  color: var(--color-primary);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  line-height: 1.5;
  border-radius: var(--radius-sm);
}
.tag--accent {
  background-color: var(--color-highlight);
  color: var(--color-accent);
}
.section--contrast .tag {
  background-color: color-mix(in srgb, var(--color-contrast-ink) 12%, transparent);
  color: var(--color-contrast-ink);
}

.panel {
  padding: var(--space-4);
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
}
.panel--outline { background-color: transparent; }
.panel--primary {
  background-color: var(--color-primary);
  border-color: transparent;
  color: var(--color-primary-ink);
}
.panel--accent {
  background-color: var(--color-accent);
  border-color: transparent;
  color: var(--color-accent-ink);
}
.panel--contrast {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}

.breadcrumb {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}
.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.breadcrumb li { margin: 0; }
.breadcrumb li + li::before {
  content: "/";
  margin-inline-end: 8px;
  color: var(--color-line);
}
.breadcrumb a {
  color: inherit;
  text-decoration: none;
}
.breadcrumb a:hover { color: var(--color-accent); }
.section--contrast .breadcrumb { color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent); }
.section--contrast .breadcrumb li + li::before { color: var(--color-contrast-line); }

/* ------------------------------------------------------------
   10. 数据带
   ------------------------------------------------------------ */
.data-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: var(--border-thin);
  background-color: var(--color-contrast-line);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.data-strip__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: var(--space-4) var(--space-3);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.data-strip__value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: var(--text-2xl);
  line-height: 1;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
}

.data-strip__value--accent { color: var(--color-contrast-accent); }

.data-strip__label {
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 64%, transparent);
}

/* ------------------------------------------------------------
   11. 主题筛选
   ------------------------------------------------------------ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  padding: 4px;
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
}

.section--contrast .filter-bar {
  background-color: color-mix(in srgb, var(--color-contrast-ink) 8%, transparent);
  border-color: var(--color-contrast-line);
}

.filter-btn {
  padding: 8px 16px;
  background-color: transparent;
  color: var(--color-ink-soft);
  border: 0;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.03em;
  transition: background-color 150ms linear, color 150ms linear;
}
.filter-btn:hover {
  background-color: var(--color-surface-deep);
  color: var(--color-ink);
}
.filter-btn[aria-pressed="true"] {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.section--contrast .filter-btn { color: var(--color-contrast-ink); }
.section--contrast .filter-btn:hover {
  background-color: color-mix(in srgb, var(--color-contrast-ink) 16%, transparent);
}
.section--contrast .filter-btn[aria-pressed="true"] {
  background-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.filter-status {
  display: block;
  margin-top: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
}
.section--contrast .filter-status {
  color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent);
}

/* ------------------------------------------------------------
   12. 图片容器（档案照片式）
   ------------------------------------------------------------ */
.figure {
  margin: 0;
  display: block;
}

.figure__media {
  position: relative;
  display: block;
  overflow: hidden;
  background-color: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
}

.figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  border: var(--border-thin) solid color-mix(in srgb, var(--color-ink) 16%, transparent);
  pointer-events: none;
}

.figure__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
}

.figure__media--16x9 { aspect-ratio: 16 / 9; }
.figure__media--4x3  { aspect-ratio: 4 / 3; }
.figure__media--3x2  { aspect-ratio: 3 / 2; }
.figure__media--1x1  { aspect-ratio: 1 / 1; }
.figure__media--21x9 { aspect-ratio: 21 / 9; }

.figure__caption {
  margin-top: var(--space-1);
  font-size: var(--text-xs);
  line-height: 1.9;
  letter-spacing: 0.05em;
  color: var(--color-ink-muted);
}

.figure__overlay {
  position: absolute;
  inset: auto 0 0 0;
  padding: var(--space-3);
  background: var(--overlay-scrim);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  line-height: 1.7;
}

.section--contrast .figure__media,
.section--primary .figure__media,
.section--accent .figure__media {
  border-color: color-mix(in srgb, currentColor 32%, transparent);
  background-color: color-mix(in srgb, var(--color-contrast-surface) 70%, transparent);
}
.section--contrast .figure__media::after,
.section--primary .figure__media::after,
.section--accent .figure__media::after {
  border-color: color-mix(in srgb, currentColor 26%, transparent);
}
.section--contrast .figure__caption,
.section--primary .figure__caption,
.section--accent .figure__caption {
  color: color-mix(in srgb, currentColor 70%, transparent);
}

/* ------------------------------------------------------------
   13. 返回顶部
   ------------------------------------------------------------ */
.to-top {
  position: fixed;
  right: var(--space-3);
  bottom: var(--space-3);
  z-index: 90;
  padding: 11px 16px;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  opacity: 0;
  visibility: hidden;
  transition: opacity 180ms linear, visibility 180ms linear, background-color 150ms linear;
}
.to-top:hover {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}
.to-top.is-visible {
  opacity: 1;
  visibility: visible;
}

/* ------------------------------------------------------------
   14. 显现
   ------------------------------------------------------------ */
.js [data-reveal] {
  opacity: 0;
  transition: opacity 240ms cubic-bezier(0.2, 0.7, 0.2, 1),
              transform 240ms cubic-bezier(0.2, 0.7, 0.2, 1);
}
.js [data-reveal="up"] { transform: translateY(8px); }
.js [data-reveal="strip"] { transform: translateX(-18px); }
.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ------------------------------------------------------------
   15. 响应式
   ------------------------------------------------------------ */
@media (max-width: 1100px) {
  .site-nav__link { padding: 9px 12px; }
  .header-bar__inner { gap: var(--space-2); }
}

@media (max-width: 900px) {
  :root {
    --gutter: 12px;
  }

  .grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .span-1, .span-2, .span-3 { grid-column: span 1; }
  .span-4, .span-5, .span-6 { grid-column: span 2; }

  .section { padding-block: calc(var(--section-y) * 0.72); }
  .section--lg { padding-block: calc(var(--section-y-lg) * 0.7); }

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

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    padding: var(--space-2) var(--space-3) var(--space-3);
    background-color: var(--color-surface);
    border-bottom: var(--border-thin) solid var(--color-line);
  }
  .site-nav[data-open="true"] { display: block; }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 1px;
    padding: 0;
    background-color: transparent;
    border: 0;
    border-radius: 0;
  }

  .site-nav__link {
    padding: 14px 16px;
    background-color: var(--color-surface-alt);
    border: var(--border-thin) solid var(--color-line);
    font-size: var(--text-base);
  }
  .site-nav__link[aria-current="page"] {
    border-color: var(--color-primary);
  }

  .site-footer__nav { margin-inline-start: 0; }
  .site-footer__inner { padding-block: var(--space-3); }
}

@media (max-width: 560px) {
  .grid { grid-template-columns: minmax(0, 1fr); }
  .span-1, .span-2, .span-3, .span-4, .span-5, .span-6 {
    grid-column: 1 / -1;
  }

  .shell { padding-inline: var(--space-2); }

  .brand__sub { display: none; }
  .header-bar__inner { min-height: 66px; }

  .ticker-note--quiet { display: none; }

  .section-title { font-size: var(--text-2xl); }
  .lede { font-size: var(--text-lg); }

  .data-strip__item { padding: var(--space-3) var(--space-2); }
  .data-strip__value { font-size: var(--text-xl); }

  .to-top {
    right: var(--space-2);
    bottom: var(--space-2);
  }
}

/* ------------------------------------------------------------
   16. 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;
  }

  .js [data-reveal],
  .js [data-reveal="up"],
  .js [data-reveal="strip"] {
    opacity: 1;
    transform: none;
  }

  .ticker-dot { opacity: 1; }
}