/* ==========================================================================
   多宝体育 · 共享样式 /assets/site.css
   夜间赛场轨道外壳：reset、变量、中文排版、头部、页脚、通用组件
   ========================================================================== */

/* ---------- 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, figure, blockquote, dl, dd {
  margin: 0;
}

ul, ol {
  padding: 0;
  list-style: none;
}

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

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

button {
  background: none;
  border: 0;
  padding: 0;
}

a {
  color: inherit;
}

sup { line-height: 0; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --ink-deep: #05140F;
  --grass: #0B241B;
  --cyan: #3DF5D0;
  --cyan-deep: #17B99A;
  --amber: #F5B33C;
  --violet: #8B5CF6;
  --paper: #F2E9D8;
  --paper-dim: #D9CDB6;
  --white: #F7FBF8;
  --mist: #9DB3A8;
  --alert: #FF6B4A;

  --font-head: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Source Han Sans SC", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --rail: 104px;
  --rail-open: 296px;
  --bar-h: 62px;
  --pad: clamp(18px, 3.4vw, 44px);
  --measure: 1240px;

  --line-cyan: rgba(61, 245, 208, 0.28);
  --line-cyan-soft: rgba(61, 245, 208, 0.16);
  --shadow-hard: 8px 8px 0 rgba(0, 0, 0, 0.5);
  --shadow-ghost: 5px 5px 0 rgba(5, 20, 15, 0.2);

  --t-fast: 90ms;
  --t-mid: 180ms;
  --t-slow: 320ms;
}

/* ---------- 3. 基础排版 ---------- */
body {
  background: var(--ink-deep);
  color: var(--white);
  font-family: var(--font-body);
  font-size: clamp(15px, 0.5vw + 13.8px, 17px);
  line-height: 1.75;
  padding-inline-start: var(--rail);
  min-height: 100%;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: 0.01em;
  margin: 0 0 0.6em;
}

h1 { font-size: clamp(2.4rem, 6vw, 4.6rem); }
h2 { font-size: clamp(1.8rem, 3.6vw, 2.9rem); }
h3 { font-size: clamp(1.25rem, 2vw, 1.62rem); }
h4 { font-size: clamp(1.02rem, 1.4vw, 1.18rem); }

p { margin: 0 0 1.2em; }

strong { font-weight: 800; }

a {
  color: var(--cyan);
  text-decoration-color: rgba(61, 245, 208, 0.45);
  text-underline-offset: 4px;
}

a:hover { color: var(--cyan-deep); }

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

:focus-visible {
  outline: 3px solid var(--amber);
  outline-offset: 3px;
}

[id] { scroll-margin-top: calc(var(--bar-h) + 24px); }

/* ---------- 4. 工具类 ---------- */
.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.container {
  width: 100%;
  max-width: var(--measure);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.mono,
.stat {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.stat {
  display: block;
  font-weight: 700;
  font-size: clamp(1.8rem, 3.4vw, 2.8rem);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--cyan);
}

.rule {
  height: 2px;
  border: 0;
  margin: 0;
  background: linear-gradient(90deg, var(--cyan), rgba(61, 245, 208, 0));
}

.grid-texture { position: relative; }

.grid-texture::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(61, 245, 208, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(61, 245, 208, 0.055) 1px, transparent 1px);
  background-size: 8px 8px;
}

.section {
  position: relative;
  padding-block: clamp(48px, 7vw, 110px);
  border-bottom: 2px solid var(--line-cyan-soft);
}

.section--paper {
  background: var(--paper);
  color: #0A1B14;
  border-bottom-color: rgba(5, 20, 15, 0.25);
}

.section--paper h1,
.section--paper h2,
.section--paper h3,
.section--paper h4 { color: #061A12; }

.section--paper a { color: #0C5744; }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: clamp(24px, 3vw, 42px);
}

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
  border: 1px solid rgba(61, 245, 208, 0.45);
  padding: 6px 12px;
  margin-bottom: 18px;
}

.section--paper .eyebrow {
  color: #0A3A2C;
  border-color: rgba(10, 58, 44, 0.5);
}

.breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mist);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
}

.breadcrumb li + li::before {
  content: "/";
  margin: 0 10px;
  color: rgba(157, 179, 168, 0.55);
}

.breadcrumb a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.breadcrumb a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 0.98rem;
  letter-spacing: 0.05em;
  padding: 13px 24px;
  border: 2px solid var(--cyan);
  color: var(--cyan);
  background: transparent;
  text-decoration: none;
  box-shadow: 5px 5px 0 rgba(61, 245, 208, 0.18);
  cursor: pointer;
  transition: background-color var(--t-mid) ease, color var(--t-mid) ease,
              border-color var(--t-mid) ease, transform var(--t-fast) ease,
              box-shadow var(--t-fast) ease;
}

.btn:hover {
  background: var(--cyan);
  color: var(--ink-deep);
  box-shadow: 7px 7px 0 rgba(61, 245, 208, 0.28);
}

.btn:active {
  transform: translate(3px, 3px);
  box-shadow: 2px 2px 0 rgba(61, 245, 208, 0.22);
}

.btn--solid {
  background: var(--cyan);
  color: var(--ink-deep);
}

.btn--solid:hover {
  background: var(--cyan-deep);
  border-color: var(--cyan-deep);
  color: var(--ink-deep);
}

.btn--ghost {
  border-color: rgba(5, 20, 15, 0.75);
  color: #08301F;
  box-shadow: var(--shadow-ghost);
}

.btn--ghost:hover {
  background: var(--ink-deep);
  border-color: var(--ink-deep);
  color: var(--paper);
  box-shadow: 7px 7px 0 rgba(5, 20, 15, 0.3);
}

/* ---------- 6. 筛选标签 ---------- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid rgba(61, 245, 208, 0.4);
  background: transparent;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background-color var(--t-mid) ease, color var(--t-mid) ease,
              border-color var(--t-mid) ease;
}

.chip:hover {
  color: var(--white);
  border-color: var(--cyan);
}

.chip[aria-pressed="true"] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink-deep);
}

/* ---------- 7. 面板与数据块 ---------- */
.panel {
  border: 2px solid var(--line-cyan);
  background: rgba(11, 36, 27, 0.72);
  box-shadow: var(--shadow-hard);
  padding: clamp(18px, 2.4vw, 28px);
}

.panel--paper {
  background: var(--paper);
  color: #0A1B14;
  border-color: #0A1B14;
  box-shadow: 8px 8px 0 rgba(5, 20, 15, 0.32);
}

.panel-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding-bottom: 12px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line-cyan);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.panel--paper .panel-head {
  border-bottom-color: rgba(5, 20, 15, 0.25);
  color: #33503F;
}

/* ---------- 8. 可展开内容组 ---------- */
.expand {
  border: 2px solid var(--line-cyan);
  background: rgba(11, 36, 27, 0.6);
  margin-bottom: 14px;
}

.expand-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 18px 20px;
  border-left: 4px solid transparent;
  color: var(--white);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.4;
  text-align: left;
  cursor: pointer;
  transition: background-color var(--t-mid) ease, border-color var(--t-mid) ease;
}

.expand-trigger:hover { background: rgba(61, 245, 208, 0.07); }

.expand-trigger[aria-expanded="true"] {
  border-left-color: var(--cyan);
  background: rgba(61, 245, 208, 0.09);
}

.expand-sign {
  position: relative;
  flex: 0 0 20px;
  height: 20px;
  border: 1px solid rgba(61, 245, 208, 0.5);
}

.expand-sign::before,
.expand-sign::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 4px;
  right: 4px;
  height: 2px;
  background: var(--cyan);
  transform: translateY(-50%);
}

.expand-sign::after {
  transform: translateY(-50%) rotate(90deg);
  transition: transform var(--t-mid) ease;
}

.expand-trigger[aria-expanded="true"] .expand-sign::after {
  transform: translateY(-50%) rotate(0deg);
}

.expand-panel {
  padding: 2px 20px 22px;
  color: #CADDD3;
  font-size: 0.96rem;
}

.expand-panel > :last-child { margin-bottom: 0; }

/* ---------- 9. 图片容器（共享基础规则，页面阶段放入真实图片） ---------- */
.figure {
  position: relative;
  margin: 0;
  border: 2px solid var(--line-cyan);
  background: var(--grass);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
}

.figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  filter: saturate(0.94) contrast(1.05) brightness(0.88);
}

.figure--wide img { aspect-ratio: 21 / 9; }
.figure--tall img { aspect-ratio: 3 / 4; }
.figure--square img { aspect-ratio: 1 / 1; }

.figure::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(
    0deg,
    rgba(5, 20, 15, 0.22) 0 2px,
    transparent 2px 4px
  );
  opacity: 0.5;
}

.figure-caption {
  position: relative;
  z-index: 1;
  padding: 10px 14px;
  border-top: 1px solid rgba(61, 245, 208, 0.24);
  background: var(--grass);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  line-height: 1.5;
}

.figure-placeholder {
  display: grid;
  place-items: center;
  aspect-ratio: 16 / 10;
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  background: repeating-linear-gradient(
    45deg,
    rgba(61, 245, 208, 0.06) 0 10px,
    transparent 10px 20px
  );
}

/* ---------- 10. 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: -90px;
  left: 14px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--cyan);
  color: var(--ink-deep);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 0.92rem;
  text-decoration: none;
  border: 2px solid var(--ink-deep);
  transition: top var(--t-mid) ease;
}

.skip-link:focus { top: 14px; }

/* ---------- 11. 侧边轨道头部 ---------- */
.site-header {
  position: fixed;
  inset-block: 0;
  inset-inline-start: 0;
  width: var(--rail);
  display: flex;
  flex-direction: column;
  background: var(--grass);
  border-inline-end: 2px solid var(--cyan);
  box-shadow: 6px 0 0 rgba(0, 0, 0, 0.35);
  z-index: 90;
  transition: width var(--t-slow) cubic-bezier(0.16, 0.84, 0.44, 1);
}

.site-header:hover,
.site-header:focus-within { width: var(--rail-open); }

.rail-top {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  min-height: 92px;
  padding: 16px 0 16px 24px;
  border-bottom: 2px solid rgba(61, 245, 208, 0.24);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  color: var(--white);
}

.brand-mark {
  flex: 0 0 52px;
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  background: var(--cyan);
  color: var(--ink-deep);
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.5rem;
  line-height: 1;
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.5);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  opacity: 0;
  transform: translateX(-10px);
  white-space: nowrap;
  transition: opacity var(--t-mid) ease, transform var(--t-mid) ease;
}

.site-header:hover .brand-text,
.site-header:focus-within .brand-text {
  opacity: 1;
  transform: none;
}

.brand-name {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.16rem;
  letter-spacing: 0.04em;
  color: var(--white);
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--amber);
}

.nav-toggle { display: none; }

.site-nav {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 14px 0 10px;
  scrollbar-width: thin;
  scrollbar-color: rgba(61, 245, 208, 0.4) transparent;
}

.nav-heading {
  padding: 8px 0 8px 22px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
  white-space: nowrap;
  opacity: 0;
  transition: opacity var(--t-mid) ease;
}

.site-header:hover .nav-heading,
.site-header:focus-within .nav-heading { opacity: 1; }

.nav-list {
  display: flex;
  flex-direction: column;
}

.nav-link {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  align-items: center;
  gap: 8px;
  min-height: 62px;
  padding: 10px 14px 10px 20px;
  border-left: 4px solid transparent;
  color: var(--mist);
  text-decoration: none;
  transition: background-color var(--t-mid) ease, color var(--t-mid) ease,
              border-color var(--t-mid) ease;
}

.nav-link:hover {
  background: rgba(61, 245, 208, 0.07);
  color: var(--white);
}

.nav-link[aria-current="page"] {
  border-left-color: var(--cyan);
  background: rgba(61, 245, 208, 0.12);
  color: var(--white);
}

.nav-index {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--amber);
  text-align: left;
}

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

.nav-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  opacity: 0;
  transform: translateX(-10px);
  white-space: nowrap;
  transition: opacity var(--t-mid) ease, transform var(--t-mid) ease;
}

.site-header:hover .nav-text,
.site-header:focus-within .nav-text {
  opacity: 1;
  transform: none;
}

.nav-label {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: 0.03em;
  color: inherit;
}

.nav-note {
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--mist);
}

.rail-foot {
  flex: 0 0 auto;
  padding: 14px 14px 20px 16px;
  border-top: 2px solid rgba(61, 245, 208, 0.24);
}

.rail-search { width: 100%; }

.rail-search-input {
  width: 100%;
  min-width: 0;
  padding: 10px 12px;
  border: 1px solid rgba(61, 245, 208, 0.38);
  border-radius: 0;
  background: rgba(61, 245, 208, 0.06);
  color: var(--white);
  font-family: var(--font-body);
  font-size: 0.84rem;
  transition: border-color var(--t-mid) ease, background-color var(--t-mid) ease;
}

.rail-search-input::placeholder { color: rgba(157, 179, 168, 0.75); }

.rail-search-input:hover,
.rail-search-input:focus {
  border-color: var(--cyan);
  background: rgba(61, 245, 208, 0.1);
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--amber) 100%);
  z-index: 120;
  pointer-events: none;
  transition: width var(--t-fast) linear;
}

/* ---------- 12. 页脚 ---------- */
.site-footer {
  position: relative;
  background: var(--paper);
  color: #0A1B14;
  border-top: 6px solid var(--ink-deep);
  padding: 0 var(--pad) clamp(24px, 3vw, 36px);
}

.footer-band {
  height: 12px;
  margin-inline: calc(var(--pad) * -1);
  background: repeating-linear-gradient(
    90deg,
    var(--amber) 0 32px,
    var(--ink-deep) 32px 64px,
    var(--cyan) 64px 96px,
    var(--violet) 96px 128px
  );
}

.footer-inner {
  max-width: var(--measure);
  margin-inline: auto;
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr 1fr;
  gap: clamp(26px, 3.4vw, 52px);
  padding-block: clamp(34px, 4.4vw, 58px) clamp(26px, 3vw, 40px);
  border-bottom: 2px solid rgba(5, 20, 15, 0.22);
}

.footer-lead {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
}

.footer-brand {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  line-height: 1.1;
  letter-spacing: 0.02em;
  color: #061A12;
}

.footer-tag {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  color: #2E4438;
}

.footer-note {
  margin: 0;
  max-width: 36ch;
  font-size: 0.92rem;
  color: #3C5145;
}

.footer-title {
  margin: 0 0 12px;
  padding-bottom: 10px;
  border-bottom: 2px solid rgba(5, 20, 15, 0.28);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: #0B241B;
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.footer-item {
  display: block;
  padding: 6px 0;
  border-bottom: 1px solid rgba(5, 20, 15, 0.1);
  font-size: 0.94rem;
  color: #33463C;
}

.footer-link {
  display: inline-block;
  padding: 6px 0;
  color: #0A1B14;
  text-decoration: none;
  background-image: linear-gradient(var(--cyan-deep), var(--cyan-deep));
  background-repeat: no-repeat;
  background-position: 0 100%;
  background-size: 0 2px;
  transition: background-size var(--t-mid) ease, color var(--t-mid) ease;
}

.footer-link:hover,
.footer-link:focus-visible {
  color: #061A12;
  background-size: 100% 2px;
}

.footer-meta {
  max-width: var(--measure);
  margin-inline: auto;
  padding-top: clamp(20px, 2.6vw, 30px);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 30px;
  font-size: 0.82rem;
  color: #3C5145;
}

.footer-contact,
.footer-address,
.footer-legal,
.footer-icp,
.footer-copy {
  margin: 0;
  line-height: 1.7;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
}

.footer-icp {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

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

/* ---------- 13. 平板 ---------- */
@media (max-width: 1080px) {
  .footer-inner { grid-template-columns: 1fr 1fr; }
}

/* ---------- 14. 移动端：轨道变顶栏 + 抽屉导航 ---------- */
@media (max-width: 900px) {
  body { padding-inline-start: 0; }

  body.is-nav-open { overflow: hidden; }

  .site-header {
    position: sticky;
    top: 0;
    left: 0;
    right: 0;
    bottom: auto;
    inset-block: auto;
    inset-inline-start: auto;
    width: 100%;
    height: var(--bar-h);
    flex-direction: row;
    align-items: center;
    border-inline-end: 0;
    border-bottom: 2px solid var(--cyan);
    box-shadow: 0 4px 0 rgba(0, 0, 0, 0.4);
  }

  .site-header:hover,
  .site-header:focus-within { width: 100%; }

  .rail-top {
    position: relative;
    z-index: 5;
    width: 100%;
    height: 100%;
    min-height: 0;
    padding: 0 16px;
    justify-content: space-between;
    border-bottom: 0;
    background: var(--grass);
  }

  .brand-text {
    opacity: 1;
    transform: none;
  }

  .brand-mark {
    flex: 0 0 38px;
    width: 38px;
    height: 38px;
    font-size: 1.08rem;
    box-shadow: 3px 3px 0 rgba(0, 0, 0, 0.5);
  }

  .brand-name { font-size: 1rem; }

  .brand-sub { display: none; }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 9px 13px;
    border: 2px solid var(--cyan);
    color: var(--cyan);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    cursor: pointer;
    transition: background-color var(--t-mid) ease, color var(--t-mid) ease;
  }

  .nav-toggle:hover { background: rgba(61, 245, 208, 0.12); }

  .nav-toggle-bars {
    position: relative;
    display: block;
    width: 20px;
    height: 2px;
    background: var(--cyan);
  }

  .nav-toggle-bars::before,
  .nav-toggle-bars::after {
    content: "";
    position: absolute;
    left: 0;
    width: 20px;
    height: 2px;
    background: var(--cyan);
    transition: transform var(--t-mid) ease;
  }

  .nav-toggle-bars::before { top: -6px; }
  .nav-toggle-bars::after { top: 6px; }

  .nav-toggle[aria-expanded="true"] .nav-toggle-bars { background: transparent; }
  .nav-toggle[aria-expanded="true"] .nav-toggle-bars::before { transform: translateY(6px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] .nav-toggle-bars::after { transform: translateY(-6px) rotate(-45deg); }

  .site-nav {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 3;
    width: min(86vw, 340px);
    padding: calc(var(--bar-h) + 18px) 0 24px;
    background: var(--grass);
    border-inline-end: 2px solid var(--cyan);
    box-shadow: 8px 0 0 rgba(0, 0, 0, 0.4);
    overflow-y: auto;
    transform: translateX(-102%);
    transition: transform var(--t-slow) cubic-bezier(0.16, 0.84, 0.44, 1);
  }

  .site-nav[data-open="true"] { transform: translateX(0); }

  .nav-heading {
    opacity: 1;
    padding-left: 24px;
  }

  .nav-text {
    opacity: 1;
    transform: none;
  }

  .nav-link { min-height: 60px; }

  .rail-foot { display: none; }

  .scroll-progress { height: 3px; }

  .footer-inner { grid-template-columns: 1fr 1fr; }
}

/* ---------- 15. 小屏 ---------- */
@media (max-width: 620px) {
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 26px;
  }

  .footer-meta {
    flex-direction: column;
    align-items: flex-start;
  }

  .btn { width: 100%; justify-content: center; }

  .section-head { flex-direction: column; align-items: flex-start; }
}

/* ---------- 16. 减少动态偏好 ---------- */
@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-progress { transition: none; }
}