/* ==========================================================================
   四季体育官网 · 共享样式表 /assets/site.css
   设计线索：堆叠面板 · 双层导航 · 四季色带 · 琥珀锚点 · 年鉴式留白
   ========================================================================== */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, p, ul, ol, dl, dt, dd, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; color: inherit; background: none; border: 0; }
button { cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; border-spacing: 0; }
[hidden] { display: none !important; }

/* ---------- 2. 变量 ---------- */
:root {
  --ink-900: #0E1512;
  --ink-700: #22302A;
  --graphite-600: #6B7570;
  --warm-white: #FAF7F1;
  --paper-200: #EFEAE0;
  --line-300: #D5CFC2;
  --amber-500: #D9822B;
  --amber-700: #9A5A12;
  --spring-500: #2F8F63;
  --summer-500: #D9541F;
  --autumn-500: #B4761F;
  --winter-500: #43678C;

  --shell: 1320px;
  --seam: 16px;
  --pad: 40px;

  --font-sans: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --shadow-soft: 0 1px 2px rgba(14, 21, 18, .04);
  --shadow-lift: 0 16px 32px -26px rgba(14, 21, 18, .75);
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 中文排版与基础 ---------- */
body {
  background: var(--warm-white);
  color: var(--ink-900);
  font-family: var(--font-sans);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4 { font-weight: 700; line-height: 1.25; letter-spacing: -.01em; }
h1 { font-size: clamp(38px, 5vw, 72px); font-weight: 200; letter-spacing: -.02em; }
h2 { font-size: clamp(26px, 3.2vw, 40px); }
h3 { font-size: clamp(19px, 1.6vw, 24px); }
p { text-wrap: pretty; }
:focus-visible { outline: 2px solid var(--amber-500); outline-offset: 2px; }
::selection { background: var(--amber-500); color: var(--ink-900); }

.skip-link {
  position: absolute; left: 20px; top: -80px; z-index: 300;
  padding: 12px 20px; background: var(--amber-500); color: var(--ink-900);
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .14em;
  transition: top .18s var(--ease);
}
.skip-link:focus { top: 16px; }
#main-content { outline: none; display: block; }

/* ---------- 4. 布局容器 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 40px);
}
.section { padding: 56px 0; }
.section--tight { padding: 32px 0; }
.stack { display: flex; flex-direction: column; gap: var(--seam); }
.stack--lg { gap: var(--pad); }
.grid { display: grid; gap: var(--seam); }
.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.col { grid-column: span 12; }
.col--3 { grid-column: span 3; }
.col--4 { grid-column: span 4; }
.col--8 { grid-column: span 8; }
.col--9 { grid-column: span 9; }
.rule { height: 1px; border: 0; background: var(--line-300); }

/* ---------- 5. 文本与数据件 ---------- */
.label {
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em;
  color: var(--graphite-600); text-transform: none;
}
.numeric {
  font-family: var(--font-mono); font-weight: 500;
  font-variant-numeric: tabular-nums; letter-spacing: .01em;
}
.section-head {
  display: flex; flex-wrap: wrap; align-items: flex-end; justify-content: space-between;
  gap: 16px; padding-bottom: 16px; border-bottom: 1px solid var(--line-300);
}
.section-head__eyebrow {
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: var(--amber-700);
}
.stat { display: flex; flex-direction: column; gap: 6px; padding: 20px 0; }
.stat__value {
  font-family: var(--font-mono); font-weight: 500; font-variant-numeric: tabular-nums;
  font-size: clamp(28px, 3.4vw, 44px); line-height: 1.1; letter-spacing: -.01em;
}
.stat__label { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: var(--graphite-600); }
.stat--amber .stat__value { color: var(--amber-700); }

/* ---------- 6. 面板 ---------- */
.panel {
  position: relative;
  background: var(--warm-white);
  border: 1px solid var(--line-300);
  box-shadow: var(--shadow-soft);
  transition: border-color .2s var(--ease), transform .2s var(--ease), box-shadow .2s var(--ease);
}
.panel:hover { border-color: var(--amber-500); transform: translateY(-2px); box-shadow: var(--shadow-lift); }
.panel__head {
  display: flex; align-items: baseline; justify-content: space-between; gap: 16px;
  padding: 18px 24px; background: var(--paper-200); border-bottom: 1px solid var(--line-300);
}
.panel__index { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: var(--amber-700); }
.panel__title { font-size: clamp(20px, 1.6vw, 26px); font-weight: 700; }
.panel__body { padding: 24px; }
.panel--ink { background: var(--ink-700); border-color: var(--ink-700); color: var(--warm-white); }
.panel--ink .panel__head { background: var(--ink-900); border-bottom-color: rgba(250, 247, 241, .14); }
.panel--ink .panel__index { color: var(--amber-500); }
.panel--ink .panel__body { color: rgba(250, 247, 241, .88); }

/* ---------- 7. 按钮与标签 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  padding: 12px 22px; border: 1px solid transparent; border-radius: 2px;
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .16em;
  text-decoration: none; transition: background-color .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease), transform .18s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--amber-500); border-color: var(--amber-500); color: var(--ink-900); }
.btn--primary:hover { background: var(--amber-700); border-color: var(--amber-700); color: var(--warm-white); }
.btn--ink { background: var(--ink-900); border-color: var(--ink-900); color: var(--warm-white); }
.btn--ink:hover { background: var(--ink-700); border-color: var(--ink-700); }
.btn--ghost { border-color: var(--line-300); color: var(--ink-900); }
.btn--ghost:hover { border-color: var(--amber-500); color: var(--amber-700); }
.btn--block { width: 100%; }

.chip {
  display: inline-flex; align-items: center; gap: 8px; padding: 6px 12px;
  border: 1px solid var(--line-300); font-family: var(--font-mono);
  font-size: 11px; letter-spacing: .14em; color: var(--graphite-600);
}
.season-tag {
  display: inline-flex; align-items: center; gap: 6px; padding: 4px 10px;
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em;
  color: var(--warm-white); background: var(--graphite-600);
}
.season-tag--spring { background: var(--spring-500); }
.season-tag--summer { background: var(--summer-500); }
.season-tag--autumn { background: var(--autumn-500); }
.season-tag--winter { background: var(--winter-500); }

/* ---------- 8. 面包屑与正文 ---------- */
.breadcrumb { padding: 18px 0 0; }
.breadcrumb__list { display: flex; flex-wrap: wrap; gap: 8px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; color: var(--graphite-600); }
.breadcrumb__item { display: flex; align-items: center; gap: 8px; }
.breadcrumb__item + .breadcrumb__item::before { content: "/"; color: var(--line-300); }
.breadcrumb__link { color: var(--graphite-600); }
.breadcrumb__link:hover { color: var(--amber-700); }

.prose { max-width: 42em; }
.prose > * + * { margin-top: 1.15em; }
.prose h2 { margin-top: 2.1em; }
.prose h3 { margin-top: 1.7em; }
.prose ul, .prose ol { padding-left: 1.4em; }
.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: .5em; }
.prose a { color: var(--amber-700); text-decoration: underline; text-underline-offset: 3px; }
.prose a:hover { color: var(--ink-900); background: rgba(217, 130, 43, .18); }

/* ---------- 9. 表格 ---------- */
.table { width: 100%; font-size: 15px; }
.table__caption {
  caption-side: top; text-align: left; padding: 0 0 12px;
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: var(--graphite-600);
}
.table th, .table td { padding: 0 16px; height: 44px; text-align: left; border-bottom: 1px solid var(--line-300); vertical-align: middle; }
.table thead th {
  background: var(--ink-900); color: var(--warm-white); height: 40px;
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; font-weight: 500;
}
.table tbody tr:nth-child(even) { background: var(--paper-200); }
.table tbody tr:hover { background: rgba(217, 130, 43, .12); }
.table td.is-numeric, .table .numeric { text-align: right; font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

/* ---------- 10. 图片容器 ---------- */
.media { margin: 0; }
.media__frame {
  position: relative; overflow: hidden; border: 1px solid var(--line-300);
  background: linear-gradient(135deg, rgba(47, 143, 99, .18) 0%, rgba(217, 84, 31, .16) 34%, rgba(180, 118, 31, .18) 66%, rgba(67, 103, 140, .20) 100%);
}
.media__frame::after {
  content: attr(data-label);
  position: absolute; left: 12px; bottom: 10px;
  padding: 3px 8px; background: rgba(250, 247, 241, .82); color: var(--ink-900);
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em;
}
.media__frame img, .media__frame svg, .media__frame video { width: 100%; height: 100%; object-fit: cover; }
.media--16x9 .media__frame { aspect-ratio: 16 / 9; }
.media--4x3 .media__frame { aspect-ratio: 4 / 3; }
.media--1x1 .media__frame { aspect-ratio: 1 / 1; }
.media__caption { margin-top: 10px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .1em; color: var(--graphite-600); }

/* ==========================================================================
   11. 共享头部
   ========================================================================== */
.site-header { position: relative; z-index: 80; background: var(--ink-900); }

.season-band { display: flex; width: 100%; height: 4px; }
.season-band__seg { flex: 1 1 25%; }
.season-band__seg--spring { background: var(--spring-500); }
.season-band__seg--summer { background: var(--summer-500); }
.season-band__seg--autumn { background: var(--autumn-500); }
.season-band__seg--winter { background: var(--winter-500); }
.season-band--footer { height: 3px; }

/* 品牌层 */
.masthead { background: var(--ink-900); color: var(--warm-white); }
.masthead__inner {
  display: flex; align-items: flex-end; justify-content: space-between;
  gap: 28px; padding: 24px 0 22px;
  transition: padding .24s var(--ease);
}
.brand { display: flex; align-items: center; gap: 16px; }
.brand__mark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 46px; height: 46px; flex: 0 0 auto;
  border: 1px solid rgba(250, 247, 241, .28);
  font-family: var(--font-mono); font-size: 13px; letter-spacing: .08em; color: var(--amber-500);
}
.brand__text { display: flex; flex-direction: column; }
.brand__name { font-size: clamp(20px, 2.2vw, 30px); font-weight: 200; letter-spacing: .02em; line-height: 1.2; }
.brand__line {
  margin-top: 4px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em;
  color: rgba(250, 247, 241, .55); transition: opacity .24s var(--ease);
}
.brand:hover .brand__name { color: var(--amber-500); }

.masthead__aside { display: flex; align-items: center; gap: 28px; }
.clock { display: flex; flex-direction: column; align-items: flex-end; gap: 2px; }
.clock__label { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: rgba(250, 247, 241, .5); }
.clock__value { font-family: var(--font-mono); font-size: 14px; letter-spacing: .06em; color: var(--amber-500); }

.util-nav { display: flex; align-items: center; gap: 6px; padding-left: 20px; border-left: 1px solid rgba(250, 247, 241, .14); }
.util-item {
  padding: 6px 10px; border: 1px solid transparent;
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .1em;
  color: rgba(250, 247, 241, .5);
}
.util-item--action { color: rgba(250, 247, 241, .82); border-color: rgba(250, 247, 241, .2); transition: border-color .18s var(--ease), color .18s var(--ease), background-color .18s var(--ease); }
.util-item--action:hover { color: var(--amber-500); border-color: var(--amber-500); background: rgba(217, 130, 43, .1); }
.util-item--action[aria-expanded="true"] { color: var(--ink-900); background: var(--amber-500); border-color: var(--amber-500); }

.js [data-site-header][data-compact] .masthead__inner { padding: 12px 0; }
.js [data-site-header][data-compact] .brand__line { opacity: 0; }

/* 栏目层 */
.nav-bar {
  position: sticky; top: 0; z-index: 90;
  background: var(--ink-700);
  border-top: 1px solid rgba(250, 247, 241, .1);
  box-shadow: 0 1px 0 rgba(14, 21, 18, .35);
}
.nav-bar__inner { display: flex; align-items: center; gap: 20px; min-height: 58px; }
.primary-nav { flex: 1 1 auto; min-width: 0; }
.primary-nav__list { display: flex; flex-wrap: wrap; align-items: stretch; }
.primary-nav__item { display: flex; }
.nav-link {
  display: flex; align-items: baseline; gap: 8px; padding: 17px 15px;
  color: rgba(250, 247, 241, .86); border-bottom: 2px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease), background-color .18s var(--ease);
}
.nav-link__index { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: rgba(250, 247, 241, .42); }
.nav-link__label { font-size: 15px; letter-spacing: .04em; }
.nav-link:hover { color: var(--warm-white); background: rgba(217, 130, 43, .12); border-bottom-color: var(--amber-500); }
.nav-link:hover .nav-link__index { color: var(--amber-500); }
.nav-link[aria-current="page"] { color: var(--amber-500); background: rgba(217, 130, 43, .1); border-bottom-color: var(--amber-500); }
.nav-link[aria-current="page"] .nav-link__index { color: var(--amber-500); }

.nav-bar__note {
  flex: 0 1 auto; white-space: nowrap;
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; color: rgba(250, 247, 241, .45);
}
.nav-bar__cta {
  flex: 0 0 auto; padding: 10px 16px; border: 1px solid var(--amber-500); color: var(--amber-500);
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em;
  transition: background-color .18s var(--ease), color .18s var(--ease);
}
.nav-bar__cta:hover { background: var(--amber-500); color: var(--ink-900); }

.nav-toggle {
  display: none; align-items: center; gap: 10px; padding: 10px 14px;
  border: 1px solid rgba(250, 247, 241, .24); color: var(--warm-white);
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .16em;
}
.nav-toggle__bars { display: block; width: 18px; height: 2px; background: currentColor; box-shadow: 0 6px 0 currentColor, 0 -6px 0 currentColor; }
.nav-toggle[aria-expanded="true"] { border-color: var(--amber-500); color: var(--amber-500); }

/* 站点索引面板 */
.site-index {
  position: absolute; left: 0; right: 0; top: 100%; z-index: 95;
  background: var(--ink-900); border-top: 1px solid var(--amber-500);
  box-shadow: 0 28px 48px -34px rgba(14, 21, 18, .9);
  animation: index-in .2s var(--ease) both;
}
@keyframes index-in { from { opacity: 0; transform: translateY(-6px); } to { opacity: 1; transform: none; } }
.site-index__inner { display: grid; grid-template-columns: minmax(220px, 1fr) 2fr; gap: 32px; padding: 28px 0 32px; }
.site-index__field { display: flex; flex-direction: column; gap: 10px; }
.site-index__label { font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em; color: rgba(250, 247, 241, .5); }
.site-index__input {
  padding: 12px 14px; border: 1px solid rgba(250, 247, 241, .24); color: var(--warm-white);
  font-family: var(--font-mono); font-size: 14px; letter-spacing: .04em;
}
.site-index__input::placeholder { color: rgba(250, 247, 241, .38); }
.site-index__input:focus { border-color: var(--amber-500); }
.site-index__hint { font-family: var(--font-mono); font-size: 11px; letter-spacing: .1em; color: rgba(250, 247, 241, .4); line-height: 1.8; }
.site-index__list { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 0 24px; }
.site-index__link {
  display: flex; align-items: baseline; justify-content: space-between; gap: 12px;
  padding: 10px 0; color: rgba(250, 247, 241, .85);
  border-bottom: 1px solid rgba(250, 247, 241, .1);
  transition: color .18s var(--ease), border-color .18s var(--ease);
}
.site-index__link:hover { color: var(--amber-500); border-bottom-color: var(--amber-500); }
.site-index__name { font-size: 15px; }
.site-index__route { font-family: var(--font-mono); font-size: 11px; color: rgba(250, 247, 241, .4); }
.site-index__empty { margin-top: 14px; font-family: var(--font-mono); font-size: 12px; letter-spacing: .1em; color: rgba(250, 247, 241, .6); }

/* ==========================================================================
   12. 共享页脚
   ========================================================================== */
.site-footer { background: var(--ink-900); color: var(--warm-white); margin-top: 0; }
.footer__inner { display: grid; grid-template-columns: 1.15fr 2fr 1.15fr; gap: 48px; padding: 60px 0 40px; }
.footer__brand-link { display: inline-block; font-size: clamp(24px, 2.6vw, 34px); font-weight: 200; letter-spacing: .02em; color: var(--warm-white); }
.footer__brand-link:hover { color: var(--amber-500); }
.footer__tagline { margin-top: 12px; font-family: var(--font-mono); font-size: 12px; letter-spacing: .1em; line-height: 1.9; color: rgba(250, 247, 241, .5); }
.footer__facts { display: flex; flex-direction: column; gap: 8px; margin-top: 22px; }
.footer__fact { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; padding-bottom: 8px; border-bottom: 1px solid rgba(250, 247, 241, .12); }
.footer__fact-key { font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; color: rgba(250, 247, 241, .45); }
.footer__fact-value { font-size: 14px; color: var(--amber-500); }

.footer__cols { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px; }
.footer__col-title { margin-bottom: 16px; font-family: var(--font-mono); font-size: 12px; font-weight: 500; letter-spacing: .16em; color: var(--amber-500); }
.footer__list { display: flex; flex-direction: column; gap: 10px; }
.footer__link { padding-bottom: 2px; border-bottom: 1px solid transparent; font-size: 15px; color: rgba(250, 247, 241, .8); transition: color .18s var(--ease), border-color .18s var(--ease); }
.footer__link:hover { color: var(--amber-500); border-bottom-color: var(--amber-500); }

.footer__contact-list { display: flex; flex-direction: column; gap: 12px; }
.footer__contact-item { display: flex; gap: 10px; font-size: 15px; color: rgba(250, 247, 241, .8); }
.footer__contact-key { flex: 0 0 42px; font-family: var(--font-mono); font-size: 11px; letter-spacing: .14em; color: rgba(250, 247, 241, .42); padding-top: 4px; }
.footer__contact-value { word-break: break-word; }
.footer__hours { margin-top: 16px; padding-top: 14px; border-top: 1px solid rgba(250, 247, 241, .12); font-size: 13px; line-height: 1.8; color: rgba(250, 247, 241, .55); }

.footer__meta {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 24px;
  padding: 20px 0; border-top: 1px solid rgba(250, 247, 241, .14);
  font-family: var(--font-mono); font-size: 12px; letter-spacing: .06em; color: rgba(250, 247, 241, .55);
}
.footer__data { max-width: 62ch; }
.footer__legal { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }
.footer__copy { color: rgba(250, 247, 241, .4); }

.footer__anchors {
  display: flex; flex-wrap: wrap; align-items: center; gap: 12px 24px;
  padding: 18px 0 30px; border-top: 1px solid rgba(250, 247, 241, .1);
}
.footer__anchor-btn {
  padding: 8px 14px; border: 1px solid rgba(250, 247, 241, .24); color: rgba(250, 247, 241, .85);
  font-family: var(--font-mono); font-size: 11px; letter-spacing: .16em;
  transition: border-color .18s var(--ease), color .18s var(--ease), background-color .18s var(--ease);
}
.footer__anchor-btn:hover { border-color: var(--amber-500); color: var(--amber-500); background: rgba(217, 130, 43, .1); }
.footer__anchor-note { font-family: var(--font-mono); font-size: 11px; letter-spacing: .12em; color: rgba(250, 247, 241, .45); }
.footer__anchor-note time { color: var(--amber-500); }

/* ---------- 13. 显现 ---------- */
.js [data-reveal] { opacity: 0; transform: translateY(8px); transition: opacity .2s var(--ease), transform .2s var(--ease); }
.js [data-reveal].is-visible { opacity: 1; transform: none; }

/* ==========================================================================
   14. 响应式
   ========================================================================== */
@media (max-width: 1180px) {
  .nav-bar__note { display: none; }
}
@media (max-width: 1080px) {
  .grid--12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .col--3, .col--4, .col--8, .col--9 { grid-column: span 6; }
  .footer__inner { grid-template-columns: 1fr 1fr; gap: 40px; }
  .footer__contact { grid-column: 1 / -1; }
}
@media (max-width: 900px) {
  .masthead__inner { flex-direction: column; align-items: flex-start; gap: 16px; padding: 20px 0 18px; }
  .masthead__aside { width: 100%; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
  .util-nav { padding-left: 0; border-left: 0; }
  .clock { align-items: flex-start; }

  .nav-bar__inner { flex-wrap: wrap; gap: 12px; padding: 10px 0; min-height: 0; }
  .nav-toggle { display: inline-flex; }
  .primary-nav { display: none; flex: 1 1 100%; order: 3; }
  .primary-nav[data-open] { display: block; }
  .primary-nav__list { flex-direction: column; border-top: 1px solid rgba(250, 247, 241, .14); }
  .primary-nav__item { display: block; }
  .nav-link { width: 100%; padding: 15px 4px; border-bottom: 1px solid rgba(250, 247, 241, .1); }
  .nav-link:hover, .nav-link[aria-current="page"] { background: rgba(217, 130, 43, .08); }
  .site-index__inner { grid-template-columns: 1fr; gap: 20px; padding: 22px 0 26px; }
}
@media (max-width: 720px) {
  body { font-size: 16px; line-height: 1.7; }
  .section { padding: 40px 0; }
  .grid--12 { grid-template-columns: 1fr; gap: 12px; }
  .col, .col--3, .col--4, .col--8, .col--9 { grid-column: 1 / -1; }
  .panel__head { flex-wrap: wrap; padding: 16px 18px; }
  .panel__body { padding: 18px; }
  .footer__inner { grid-template-columns: 1fr; gap: 32px; padding: 44px 0 32px; }
  .footer__cols { grid-template-columns: 1fr 1fr; gap: 24px; }
  .footer__meta { flex-direction: column; align-items: flex-start; }
  .footer__contact-key { flex-basis: 38px; }
  .table th, .table td { padding: 0 10px; height: 42px; }
}
@media (max-width: 520px) {
  .brand__mark { width: 38px; height: 38px; font-size: 12px; }
  .footer__cols { grid-template-columns: 1fr; }
  .util-item { padding: 6px 8px; font-size: 11px; }
  .site-index__list { grid-template-columns: 1fr; }
  .footer__anchor-note { width: 100%; }
}

/* ---------- 15. 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
  .panel:hover, .btn:hover { transform: none; }
  .site-index { animation: none; }
  .js [data-reveal] { opacity: 1; transform: none; }
}