/* ==========================================================================
   冠军赛场 · 赛季档案室 / 共享样式表 site.css
   结构：变量 → 重置 → 排版 → 头部 → 导航 → 页脚 → 通用组件 → 响应式
   ========================================================================== */

/* ---------- 1. 设计变量 ---------- */
:root {
  --ink-green: #0E2B26;
  --night-blue: #101B2E;
  --deep-black-green: #071310;
  --gold: #E3B23C;
  --gold-soft: #F0C458;
  --whistle: #F26B2A;
  --turf: #1F6F5C;
  --paper: #F4F1E8;
  --archive: #9AA3A0;
  --discipline-yellow: #E8C33A;
  --discipline-red: #C0392B;

  --shell: 1320px;
  --gutter: 28px;
  --header-h: 78px;

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

  --line-soft: rgba(154, 163, 160, 0.22);
  --line-gold: rgba(227, 178, 60, 0.3);
}

/* ---------- 2. 重置 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  background-color: var(--ink-green);
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.85;
  font-variant-numeric: tabular-nums;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
h4,
h5 {
  margin: 0 0 0.6em;
  font-weight: 800;
  line-height: 1.28;
  letter-spacing: 0.01em;
}

p {
  margin: 0 0 1em;
}

ul,
ol {
  margin: 0;
  padding: 0;
}

li {
  list-style: none;
}

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

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

table {
  border-collapse: collapse;
  width: 100%;
}

hr {
  border: 0;
}

/* ---------- 3. 焦点与无障碍 ---------- */
:focus-visible {
  outline: 3px solid var(--whistle);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: -90px;
  left: 16px;
  z-index: 999;
  padding: 12px 20px;
  background: var(--gold);
  color: var(--deep-black-green);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  border: 2px solid var(--deep-black-green);
  transition: top 0.22s ease;
}

.skip-link:focus {
  top: 12px;
}

/* ---------- 4. 头部骨架 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background-color: transparent;
  border-bottom: 2px solid transparent;
  transition: background-color 0.32s ease, border-color 0.32s ease,
    box-shadow 0.32s ease;
}

.site-header[data-pinned="true"] {
  background-color: rgba(16, 27, 46, 0.95);
  border-bottom-color: rgba(227, 178, 60, 0.36);
  box-shadow: 0 14px 34px rgba(3, 10, 8, 0.42);
  -webkit-backdrop-filter: blur(14px) saturate(130%);
  backdrop-filter: blur(14px) saturate(130%);
}

.header-inner {
  position: relative;
  width: min(calc(100% - var(--gutter) * 2), var(--shell));
  margin-inline: auto;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 26px;
}

.header-inner::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(154, 163, 160, 0.45) 0 1px,
    transparent 1px 14px
  );
  opacity: 0;
  transition: opacity 0.32s ease;
  pointer-events: none;
}

.site-header[data-pinned="true"] .header-inner::after {
  opacity: 0.85;
}

/* ---------- 5. 品牌字标 ---------- */
.brand {
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--paper);
}

.brand-mark {
  position: relative;
  flex: none;
  width: 36px;
  height: 36px;
  border: 2px solid var(--gold);
  background-image: linear-gradient(
    135deg,
    rgba(227, 178, 60, 0.22),
    transparent 62%
  );
}

.brand-mark::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 13px;
  height: 13px;
  transform: translate(-50%, -50%) rotate(45deg);
  border: 2px solid var(--gold);
}

.brand-mark::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 4px;
  width: 15px;
  height: 2px;
  transform: translateX(-50%);
  background: var(--whistle);
}

.brand-name {
  display: block;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.14em;
  line-height: 1.05;
}

.brand-sub {
  display: block;
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.26em;
  color: var(--gold);
  text-transform: uppercase;
}

/* ---------- 6. 主导航 ---------- */
.site-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-link {
  display: block;
  padding: 8px 12px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: rgba(244, 241, 232, 0.82);
  white-space: nowrap;
  transition: color 0.2s ease, background-color 0.2s ease,
    border-color 0.2s ease;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: #ffffff;
}

.nav-link[aria-current="page"] {
  color: var(--gold);
}

@media (min-width: 901px) {
  .nav-link {
    border-bottom: 2px solid transparent;
  }

  .nav-link:hover,
  .nav-link:focus-visible {
    border-bottom-color: var(--whistle);
  }

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

/* ---------- 7. 头部工具区 ---------- */
.header-tools {
  flex: none;
  display: flex;
  align-items: center;
  gap: 14px;
}

.season-switch {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  border: 1px solid var(--line-gold);
  background: rgba(7, 19, 16, 0.4);
}

.season-switch-label {
  padding: 0 8px 0 6px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.2em;
  color: var(--archive);
}

.season-btn {
  min-width: 46px;
  height: 30px;
  padding: 0 8px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: rgba(244, 241, 232, 0.68);
  border: 1px solid transparent;
  transition: color 0.2s ease, background-color 0.2s ease,
    border-color 0.2s ease;
}

.season-btn:hover {
  color: var(--paper);
  border-color: rgba(154, 163, 160, 0.4);
}

.season-btn[aria-pressed="true"] {
  background-color: var(--gold);
  border-color: var(--gold);
  color: var(--deep-black-green);
  font-weight: 700;
}

.header-search {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  height: 42px;
  padding: 0 15px;
  border: 1px solid rgba(244, 241, 232, 0.3);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: rgba(244, 241, 232, 0.85);
  transition: border-color 0.2s ease, color 0.2s ease,
    background-color 0.2s ease;
}

.header-search:hover,
.header-search:focus-visible {
  border-color: var(--gold);
  color: var(--gold);
  background-color: rgba(227, 178, 60, 0.08);
}

.header-search-icon {
  position: relative;
  flex: none;
  width: 13px;
  height: 13px;
}

.header-search-icon::before,
.header-search-icon::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border: 1.8px solid currentColor;
}

.header-search-icon::before {
  top: 0;
  left: 0;
  border-right: 0;
  border-bottom: 0;
}

.header-search-icon::after {
  right: 0;
  bottom: 0;
  border-left: 0;
  border-top: 0;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  height: 42px;
  min-width: 42px;
  padding: 0 13px;
  border: 1px solid rgba(244, 241, 232, 0.32);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.nav-toggle:hover,
.nav-toggle:focus-visible {
  border-color: var(--gold);
  color: var(--gold);
}

.nav-toggle-glyph {
  position: relative;
  display: block;
  flex: none;
  width: 17px;
  height: 12px;
}

.nav-toggle-glyph::before,
.nav-toggle-glyph::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: currentColor;
  transition: transform 0.25s ease;
}

.nav-toggle-glyph::before {
  top: 1px;
}

.nav-toggle-glyph::after {
  bottom: 1px;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-glyph::before {
  transform: translateY(4px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-glyph::after {
  transform: translateY(-4px) rotate(-45deg);
}

/* ---------- 8. 阅读进度条 ---------- */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background-image: linear-gradient(90deg, var(--gold), var(--whistle));
  transform: scaleX(0);
  transform-origin: 0 50%;
  will-change: transform;
  pointer-events: none;
}

/* ---------- 9. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background-color: var(--deep-black-green);
  border-top: 2px solid var(--gold);
  color: rgba(244, 241, 232, 0.78);
  padding: 74px 0 30px;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(
      rgba(154, 163, 160, 0.06) 1px,
      transparent 1px
    ),
    linear-gradient(90deg, rgba(154, 163, 160, 0.06) 1px, transparent 1px);
  background-size: 72px 72px;
}

.site-footer::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 220px;
  height: 3px;
  background-image: linear-gradient(90deg, var(--whistle), transparent);
  pointer-events: none;
}

.footer-inner {
  position: relative;
  z-index: 1;
  width: min(calc(100% - var(--gutter) * 2), var(--shell));
  margin-inline: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.5fr 1.4fr;
  gap: 48px 42px;
}

.footer-col {
  min-width: 0;
}

.footer-col-title {
  margin: 0 0 18px;
  padding-bottom: 11px;
  border-bottom: 1px solid var(--line-gold);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
}

.footer-brand {
  margin: 0 0 14px;
  font-size: 26px;
  font-weight: 800;
  letter-spacing: 0.16em;
  line-height: 1.1;
  color: var(--paper);
}

.footer-note {
  margin: 0 0 18px;
  max-width: 34ch;
  font-size: 14.5px;
  line-height: 1.85;
  color: rgba(244, 241, 232, 0.66);
}

.footer-stamp {
  margin: 0;
  color: var(--turf);
  letter-spacing: 0.14em;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-link {
  display: inline-block;
  padding: 6px 0;
  font-size: 15px;
  color: rgba(244, 241, 232, 0.78);
  transition: color 0.2s ease, transform 0.2s ease;
}

.footer-link::before {
  content: "";
  display: inline-block;
  width: 0;
  height: 1px;
  margin-right: 0;
  background: var(--whistle);
  vertical-align: middle;
  transition: width 0.22s ease, margin-right 0.22s ease;
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--gold);
}

.footer-link:hover::before,
.footer-link:focus-visible::before {
  width: 12px;
  margin-right: 8px;
}

.footer-link-sm {
  font-size: 13px;
  padding: 4px 0;
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 16px;
}

.footer-contact-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.footer-contact-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--archive);
}

.footer-contact-value {
  font-size: 15px;
  line-height: 1.7;
  color: var(--paper);
  word-break: break-word;
}

.footer-service {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.85;
  color: rgba(244, 241, 232, 0.6);
}

.footer-icp {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px solid rgba(154, 163, 160, 0.18);
  color: var(--archive);
  letter-spacing: 0.1em;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px 28px;
  margin-top: 54px;
  padding-top: 22px;
  border-top: 1px solid rgba(154, 163, 160, 0.2);
}

.footer-copy {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: rgba(244, 241, 232, 0.55);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 20px;
}

/* ---------- 10. 布局容器 ---------- */
.container {
  width: min(calc(100% - var(--gutter) * 2), var(--shell));
  margin-inline: auto;
}

.container-narrow {
  width: min(calc(100% - var(--gutter) * 2), 880px);
  margin-inline: auto;
}

.page-offset {
  padding-top: calc(var(--header-h) + 52px);
}

.section {
  padding: 88px 0;
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 22px 32px;
  margin-bottom: 38px;
}

.on-paper {
  background-color: var(--paper);
  color: var(--ink-green);
}

.on-paper .lede {
  color: rgba(14, 43, 38, 0.8);
}

.on-paper .card {
  background-color: #ffffff;
  border-color: rgba(14, 43, 38, 0.18);
}

.on-paper .card-title {
  color: var(--ink-green);
}

.on-paper .card-text {
  color: rgba(14, 43, 38, 0.72);
}

/* ---------- 11. 文字组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--whistle);
}

.eyebrow::before {
  content: "";
  flex: none;
  width: 30px;
  height: 2px;
  background: var(--whistle);
}

.lede {
  max-width: 64ch;
  margin: 0;
  font-size: 18.5px;
  line-height: 1.9;
  color: rgba(244, 241, 232, 0.82);
}

.data-mono {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--archive);
}

.divider-rule {
  height: 1px;
  margin: 42px 0;
  background-image: linear-gradient(
    90deg,
    rgba(227, 178, 60, 0.55),
    rgba(154, 163, 160, 0.14) 68%,
    transparent
  );
}

.prose {
  max-width: 68ch;
  font-size: 17.5px;
  line-height: 1.92;
}

.prose > * + * {
  margin-top: 1.05em;
}

.prose h2 {
  margin-top: 1.9em;
  font-size: 28px;
}

.prose h3 {
  margin-top: 1.6em;
  font-size: 21px;
}

.prose a {
  color: var(--whistle);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.prose code {
  padding: 2px 6px;
  font-family: var(--font-mono);
  font-size: 0.92em;
  background: rgba(154, 163, 160, 0.18);
}

.prose blockquote {
  margin: 1.6em 0;
  padding: 4px 0 4px 20px;
  border-left: 3px solid var(--gold);
  color: rgba(244, 241, 232, 0.76);
}

.on-paper .prose blockquote {
  color: rgba(14, 43, 38, 0.76);
}

/* ---------- 12. 网格 ---------- */
.grid {
  display: grid;
  gap: 22px;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

/* ---------- 13. 卡片与标签 ---------- */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 30px 26px 26px;
  background-color: rgba(16, 27, 46, 0.74);
  border: 2px solid var(--line-soft);
  transition: border-color 0.22s ease, transform 0.22s ease,
    background-color 0.22s ease;
}

.card:hover {
  border-color: rgba(227, 178, 60, 0.55);
  transform: translateY(-3px);
}

.card-tag {
  position: absolute;
  top: -2px;
  left: -2px;
  padding: 4px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  background-color: var(--turf);
  color: #06120f;
}

.card-title {
  margin: 6px 0 0;
  font-size: 21px;
  font-weight: 800;
  line-height: 1.4;
  color: var(--paper);
}

.card-text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.8;
  color: rgba(244, 241, 232, 0.72);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid currentColor;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--archive);
}

.tag-gold {
  color: var(--gold);
}

.tag-orange {
  color: var(--whistle);
}

.tag-yellow {
  color: var(--discipline-yellow);
}

.tag-red {
  color: var(--discipline-red);
}

/* ---------- 14. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 12px 28px;
  font-size: 15.5px;
  font-weight: 700;
  letter-spacing: 0.08em;
  border: 2px solid transparent;
  text-align: center;
  transition: background-color 0.2s ease, border-color 0.2s ease,
    color 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background-color: var(--gold);
  border-color: var(--gold);
  color: var(--deep-black-green);
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background-color: var(--gold-soft);
  border-color: var(--gold-soft);
}

.btn-ghost {
  background-color: transparent;
  border-color: rgba(244, 241, 232, 0.42);
  color: var(--paper);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--gold);
  color: var(--gold);
}

.btn-line {
  background-color: transparent;
  border-color: var(--whistle);
  color: var(--whistle);
}

.btn-line:hover,
.btn-line:focus-visible {
  background-color: var(--whistle);
  color: var(--deep-black-green);
}

/* ---------- 15. 面包屑 ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--archive);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb-item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  color: rgba(154, 163, 160, 0.45);
}

.breadcrumb-item a {
  color: var(--archive);
  transition: color 0.2s ease;
}

.breadcrumb-item a:hover,
.breadcrumb-item a:focus-visible {
  color: var(--gold);
}

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

/* ---------- 16. 图片容器 ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  margin: 0;
  background-color: #0B1A24;
  border: 2px solid var(--line-soft);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.88) contrast(1.05);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(
    180deg,
    rgba(7, 19, 16, 0.1) 0%,
    rgba(7, 19, 16, 0) 42%,
    rgba(7, 19, 16, 0.78) 100%
  );
}

.media-frame[data-ratio="21x9"] {
  aspect-ratio: 21 / 9;
}

.media-frame[data-ratio="16x9"] {
  aspect-ratio: 16 / 9;
}

.media-frame[data-ratio="4x3"] {
  aspect-ratio: 4 / 3;
}

.media-frame[data-ratio="1x1"] {
  aspect-ratio: 1 / 1;
}

.media-frame[data-ratio="3x4"] {
  aspect-ratio: 3 / 4;
}

.media-cap {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--archive);
}

/* ---------- 17. 非对称双栏与索引栏 ---------- */
.layout-split {
  display: flex;
  align-items: flex-start;
  gap: 52px;
}

.index-rail {
  position: sticky;
  top: calc(var(--header-h) + 26px);
  flex: none;
  width: 262px;
  align-self: flex-start;
}

.main-col {
  flex: 1 1 auto;
  min-width: 0;
}

/* ---------- 18. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 180;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 46px;
  padding: 10px 18px;
  background-color: rgba(7, 19, 16, 0.92);
  border: 2px solid var(--gold);
  color: var(--gold);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  opacity: 0;
  transform: translateY(16px);
  pointer-events: none;
  transition: opacity 0.28s ease, transform 0.28s ease,
    background-color 0.2s ease, color 0.2s ease;
}

.to-top[data-visible="true"] {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.to-top:hover,
.to-top:focus-visible {
  background-color: var(--gold);
  color: var(--deep-black-green);
}

.to-top-arrow {
  width: 0;
  height: 0;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-bottom: 8px solid currentColor;
}

.to-top-text {
  line-height: 1;
}

/* ---------- 19. 响应式 ---------- */
@media (max-width: 1180px) {
  .nav-link {
    padding: 8px 9px;
    font-size: 14.5px;
  }

  .header-inner {
    gap: 18px;
  }
}

@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .layout-split {
    flex-direction: column;
    gap: 34px;
  }

  .index-rail {
    position: static;
    top: auto;
    width: 100%;
  }
}

@media (max-width: 900px) {
  :root {
    --gutter: 18px;
    --header-h: 64px;
  }

  body {
    font-size: 16.5px;
  }

  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    justify-content: flex-start;
    padding: 10px var(--gutter) 26px;
    background-color: rgba(7, 19, 16, 0.98);
    border-bottom: 2px solid var(--gold);
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
  }

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

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-link {
    padding: 15px 4px;
    font-size: 17px;
    border-bottom: 1px solid rgba(154, 163, 160, 0.16);
    border-left: 2px solid transparent;
  }

  .nav-link:hover,
  .nav-link:focus-visible {
    border-left-color: var(--whistle);
  }

  .nav-link[aria-current="page"] {
    border-left-color: var(--gold);
  }

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

  body.nav-open {
    overflow: hidden;
  }

  .section {
    padding: 60px 0;
  }

  .page-offset {
    padding-top: calc(var(--header-h) + 34px);
  }

  .site-footer {
    padding-top: 56px;
  }

  .footer-bottom {
    margin-top: 38px;
  }
}

@media (max-width: 680px) {
  .brand-sub {
    display: none;
  }

  .brand-name {
    font-size: 17.5px;
    letter-spacing: 0.1em;
  }

  .brand-mark {
    width: 30px;
    height: 30px;
  }

  .brand-mark::before {
    width: 10px;
    height: 10px;
  }

  .brand-mark::after {
    width: 12px;
  }

  .season-switch-label {
    display: none;
  }

  .season-btn {
    min-width: 38px;
    height: 28px;
    padding: 0 5px;
    font-size: 11.5px;
  }

  .header-search-text {
    display: none;
  }

  .header-search {
    padding: 0 12px;
  }

  .nav-toggle-label {
    display: none;
  }

  .nav-toggle {
    padding: 0 11px;
  }

  .header-tools {
    gap: 9px;
  }

  .header-inner {
    gap: 12px;
  }

  .grid-2,
  .grid-3,
  .grid-4,
  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .footer-grid {
    gap: 34px;
  }

  .section {
    padding: 48px 0;
  }

  .to-top {
    right: 14px;
    bottom: 14px;
    padding: 9px 14px;
  }
}

/* ---------- 20. 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;
    scroll-behavior: auto !important;
  }

  .card:hover,
  .btn:hover {
    transform: none;
  }
}