/* ============================================================
   天梭看台 · 共享站点样式 /assets/site.css
   记分牌底型：吸顶刻度带 + 非对称 12 列网格 + 三层页脚
   ============================================================ */

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

:root {
  /* 品牌矿物色体系 */
  --navy: #003057;
  --navy-deep: #00223D;
  --red: #E2001A;
  --red-deep: #A80013;
  --cyan: #00E0C6;
  --white: #F8F9F8;
  --paper: #F2EDE4;
  --silver: #C3C9CE;
  --stone: #6B7076;
  --moss: #3F5B4A;

  --line-soft: rgba(195, 201, 206, 0.22);
  --line-mid: rgba(195, 201, 206, 0.34);
  --on-dark-mute: rgba(248, 249, 248, 0.66);

  /* 字体 */
  --font-body: "PingFang SC", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-title: "PingFang SC", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", "Arial Narrow", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  /* 尺度 */
  --step-xs: 12px;
  --step-sm: 14px;
  --step-md: 17px;
  --step-lg: 20px;
  --step-xl: clamp(24px, 3vw, 32px);
  --step-2xl: clamp(32px, 4.4vw, 46px);
  --step-3xl: clamp(40px, 6vw, 64px);
  --step-num: clamp(56px, 9vw, 140px);

  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 48px;
  --sp-8: 72px;

  --rail: 1280px;
  --gutter: clamp(20px, 4vw, 40px);
  --radius: 2px;
  --tick: 200ms;
  --nav-height: 62px;
}

/* ---------- Reset ---------- */
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  min-height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--navy);
  background-image:
    linear-gradient(180deg, rgba(0, 34, 61, 0.55) 0%, rgba(0, 48, 87, 0) 42%),
    repeating-linear-gradient(90deg, rgba(195, 201, 206, 0.06) 0 1px, transparent 1px 96px);
  color: var(--white);
  font-family: var(--font-body);
  font-size: var(--step-md);
  line-height: 1.75;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
}

#main-content { flex: 1 0 auto; }

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 var(--sp-4);
  font-family: var(--font-title);
  font-weight: 900;
  line-height: 1.16;
  letter-spacing: -0.01em;
}

h1 { font-size: var(--step-3xl); }
h2 { font-size: var(--step-2xl); }
h3 { font-size: var(--step-xl); }
h4 { font-size: var(--step-lg); }

p { margin: 0 0 var(--sp-4); }

p:last-child, ul:last-child, ol:last-child { margin-bottom: 0; }

a { color: var(--cyan); text-decoration: none; }
a:hover { text-decoration: underline; }

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

ul, ol { margin: 0 0 var(--sp-4); padding-left: 1.25em; }

button { font: inherit; color: inherit; }

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

hr { border: 0; border-top: 1px solid var(--line-soft); margin: var(--sp-6) 0; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 1px;
}

::selection { background: var(--red); color: var(--white); }

/* ---------- 跳转链接 ---------- */
.skip-link {
  position: absolute;
  left: var(--sp-4);
  top: -120px;
  z-index: 300;
  display: inline-block;
  padding: 11px 18px;
  background: var(--cyan);
  color: var(--navy-deep);
  font-size: var(--step-sm);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-decoration: none;
  border-radius: var(--radius);
  transition: top 160ms ease-out;
}
.skip-link:focus { top: 12px; text-decoration: none; }

/* ============================================================
   头部：左右分置看台条
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background: var(--navy);
  color: var(--white);
  border-bottom: 1px solid var(--line-soft);
  box-shadow: 0 14px 34px rgba(0, 22, 40, 0.36);
}

.header-rail {
  width: min(var(--rail), 100% - (var(--gutter) * 2));
  margin-inline: auto;
  padding-block: 10px;
}

.header-inner {
  display: flex;
  align-items: center;
  gap: clamp(16px, 3vw, 56px);
  min-height: var(--nav-height);
}

/* 品牌 */
.brand,
.footer-brand {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  flex: 0 0 auto;
  text-decoration: none;
}
.brand:hover, .footer-brand:hover { text-decoration: none; }

.brand-mark {
  font-family: var(--font-title);
  font-weight: 900;
  font-size: 22px;
  line-height: 1.05;
  letter-spacing: 0.14em;
  color: var(--white);
  text-transform: uppercase;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 10px;
  line-height: 1.4;
  letter-spacing: 0.24em;
  color: var(--cyan);
}

/* 导航刻度 */
.site-nav { margin-left: auto; }

.nav-list {
  display: flex;
  align-items: stretch;
  flex-wrap: nowrap;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-list > li { flex: 0 0 auto; }

.nav-link {
  position: relative;
  display: block;
  padding: 11px 15px;
  font-size: var(--step-sm);
  letter-spacing: 0.06em;
  color: var(--on-dark-mute);
  text-decoration: none;
  border-left: 1px solid var(--line-soft);
  transition: color var(--tick) linear, background-color var(--tick) linear;
}
.nav-list > li:last-child .nav-link { border-right: 1px solid var(--line-soft); }

.nav-link::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 5px;
  height: 2px;
  background: var(--red);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform var(--tick) ease-out;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--white);
  background: rgba(248, 249, 248, 0.07);
  text-decoration: none;
}
.nav-link:hover::after { transform: scaleX(1); }

.nav-link[aria-current="page"] {
  color: var(--white);
  background: rgba(0, 224, 198, 0.12);
}
.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--cyan);
}

/* 工具区 */
.header-tools {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  flex: 0 0 auto;
}

.device-switch {
  display: inline-flex;
  padding: 3px;
  gap: 2px;
  border: 1px solid var(--line-mid);
  border-radius: var(--radius);
  background: rgba(0, 34, 61, 0.72);
}

.device-btn {
  appearance: none;
  border: 0;
  background: transparent;
  padding: 6px 11px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: rgba(248, 249, 248, 0.58);
  border-radius: 1px;
  cursor: pointer;
  transition: background-color var(--tick) linear, color var(--tick) linear;
}
.device-btn:hover { color: var(--white); }
.device-btn[aria-pressed="true"] {
  background: var(--red);
  color: var(--white);
}

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--sp-2);
  appearance: none;
  border: 1px solid var(--line-mid);
  background: transparent;
  color: var(--white);
  padding: 9px 13px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  cursor: pointer;
  border-radius: var(--radius);
  transition: border-color var(--tick) linear, color var(--tick) linear;
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }

.nav-toggle-bars {
  position: relative;
  display: inline-block;
  width: 16px;
  height: 10px;
}
.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--cyan);
  transition: transform var(--tick) ease-out;
}
.nav-toggle-bars::before { top: 0; }
.nav-toggle-bars::after { bottom: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::before { transform: translateY(4px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::after { transform: translateY(-4px) rotate(-45deg); }

/* 进度线 */
.read-progress {
  height: 2px;
  background: rgba(248, 249, 248, 0.13);
  overflow: hidden;
}
.read-progress-fill {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--red);
  transform: scaleX(0);
  transform-origin: 0 50%;
  will-change: transform;
}

/* ============================================================
   通用容器与章节
   ============================================================ */
.container {
  width: min(var(--rail), 100% - (var(--gutter) * 2));
  margin-inline: auto;
}

.section { padding-block: clamp(44px, 6.5vw, 92px); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--sp-5);
  margin-bottom: clamp(24px, 3.4vw, 44px);
  padding-bottom: var(--sp-4);
  border-bottom: 1px solid var(--line-soft);
}

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

.section-subtitle {
  margin: 0;
  max-width: 46ch;
  color: var(--on-dark-mute);
  font-size: var(--step-sm);
  line-height: 1.8;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  margin-bottom: var(--sp-3);
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cyan);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 2px;
  background: var(--red);
  flex: 0 0 auto;
}

/* ============================================================
   非对称 12 列网格
   ============================================================ */
.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2.4vw, 34px);
}

.col-side { grid-column: 1 / span 3; }
.col-main { grid-column: 5 / span 8; }
.col-main--edge { grid-column: 4 / span 9; }
.col-note { grid-column: 9 / span 4; }
.col-half { grid-column: span 6; }
.col-full { grid-column: 1 / -1; }

/* ============================================================
   卡片层：实色内容层与玻璃索引层
   ============================================================ */
.card {
  background: var(--white);
  color: var(--navy);
  border: 1px solid var(--silver);
  border-radius: var(--radius);
  padding: clamp(18px, 2.4vw, 30px);
}

.card--dark {
  background: var(--navy-deep);
  color: var(--white);
  border-color: var(--line-soft);
}

.card--paper {
  background: var(--paper);
  color: var(--navy);
  border-color: #DCD3C4;
}

.card--glass {
  background: rgba(248, 249, 248, 0.06);
  border: 1px solid var(--line-soft);
  color: var(--white);
  backdrop-filter: blur(9px);
  -webkit-backdrop-filter: blur(9px);
}

.card-title {
  margin: 0 0 var(--sp-3);
  font-size: var(--step-lg);
  letter-spacing: 0.01em;
}

.card-text {
  margin: 0;
  font-size: var(--step-sm);
  line-height: 1.8;
}

.card--dark .card-text,
.card--glass .card-text { color: var(--on-dark-mute); }

/* ============================================================
   按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: 14px 24px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: var(--step-sm);
  font-weight: 700;
  letter-spacing: 0.06em;
  line-height: 1;
  text-decoration: none;
  cursor: pointer;
  transition: background-color var(--tick) linear, color var(--tick) linear,
              border-color var(--tick) linear, transform var(--tick) ease-out;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--primary { background: var(--red); color: var(--white); }
.btn--primary:hover { background: var(--red-deep); color: var(--white); }

.btn--ghost {
  background: transparent;
  color: var(--white);
  border-color: var(--line-mid);
}
.btn--ghost:hover { border-color: var(--cyan); color: var(--cyan); }

.btn--quiet {
  background: transparent;
  color: var(--navy);
  border-color: var(--silver);
}
.btn--quiet:hover { border-color: var(--red); color: var(--red); }

/* ============================================================
   标签筛选
   ============================================================ */
.chip-group {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  margin: 0 0 var(--sp-5);
  padding: 0;
  list-style: none;
}

.chip {
  appearance: none;
  display: inline-flex;
  align-items: center;
  padding: 7px 14px;
  border: 1px solid var(--line-mid);
  border-radius: 999px;
  background: transparent;
  color: var(--on-dark-mute);
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.08em;
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--tick) linear, color var(--tick) linear, border-color var(--tick) linear;
}
.chip:hover { border-color: var(--cyan); color: var(--cyan); text-decoration: none; }
.chip[aria-pressed="true"] {
  background: var(--red);
  border-color: var(--red);
  color: var(--white);
}

/* ============================================================
   数据数字
   ============================================================ */
.mono-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
  letter-spacing: -0.015em;
}

.stat-figure { margin: 0; }

.stat-value {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: var(--step-num);
  line-height: 0.94;
  letter-spacing: -0.03em;
  color: var(--red);
}

.stat-label {
  display: block;
  margin-top: var(--sp-3);
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.14em;
  color: var(--silver);
}

/* ============================================================
   折叠卡片
   ============================================================ */
.accordion {
  background: var(--white);
  color: var(--navy);
  border: 1px solid var(--silver);
  border-radius: var(--radius);
  overflow: hidden;
}
.accordion + .accordion { margin-top: var(--sp-3); }

.accordion > summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  padding: 18px 22px;
  font-size: var(--step-md);
  font-weight: 700;
  line-height: 1.5;
  cursor: pointer;
  list-style: none;
  transition: background-color var(--tick) linear, color var(--tick) linear;
}
.accordion > summary::-webkit-details-marker { display: none; }
.accordion > summary:hover { background: var(--paper); }
.accordion > summary::after {
  content: "";
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--red);
  border-bottom: 2px solid var(--red);
  transform: rotate(45deg);
  transition: transform 240ms ease-out;
}
.accordion[open] > summary { background: var(--paper); }
.accordion[open] > summary::after { transform: rotate(-135deg); }

.accordion-body {
  padding: 0 22px 22px;
  font-size: var(--step-sm);
  line-height: 1.85;
  color: #33414D;
}

/* ============================================================
   图片容器（页面阶段放 <img> 占位）
   ============================================================ */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  width: 100%;
  aspect-ratio: 16 / 10;
  background-color: var(--navy-deep);
  background-image:
    linear-gradient(125deg, rgba(0, 48, 87, 0.9) 0%, rgba(0, 34, 61, 0.95) 62%),
    repeating-linear-gradient(90deg, rgba(195, 201, 206, 0.14) 0 1px, transparent 1px 42px);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: relative;
  z-index: 1;
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background: linear-gradient(122deg, rgba(0, 48, 87, 0) 52%, rgba(0, 224, 198, 0.16) 100%);
}

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

.media-frame__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 3;
  margin: 0;
  padding: 10px 16px;
  width: 100%;
  background: linear-gradient(0deg, rgba(0, 34, 61, 0.9), rgba(0, 34, 61, 0));
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.1em;
  color: var(--white);
}

/* ============================================================
   面包屑
   ============================================================ */
.breadcrumbs { padding-top: var(--sp-5); }

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-2);
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.1em;
  color: var(--silver);
}

.breadcrumb-list > li { display: inline-flex; align-items: center; gap: var(--sp-2); }
.breadcrumb-list > li + li::before { content: "/"; color: rgba(195, 201, 206, 0.5); }

.breadcrumb-link { color: var(--cyan); text-decoration: none; }
.breadcrumb-link:hover { text-decoration: underline; }

/* ============================================================
   滚动显现 / 章节高亮
   ============================================================ */
[data-reveal] { opacity: 1; transform: none; }

html.js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 280ms ease-out, transform 280ms ease-out;
}
html.js [data-reveal].is-visible { opacity: 1; transform: none; }

[data-spy] { transition: color var(--tick) linear, border-color var(--tick) linear; }
[data-spy].is-active {
  color: var(--white);
  border-color: var(--red) !important;
}

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  background: var(--navy-deep);
  color: var(--white);
  border-top: 1px solid var(--line-soft);
}

.footer-rail {
  width: min(var(--rail), 100% - (var(--gutter) * 2));
  margin-inline: auto;
  padding-block: clamp(40px, 5vw, 64px) var(--sp-6);
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--sp-5);
  padding-bottom: var(--sp-5);
  border-bottom: 1px solid var(--line-soft);
}

.footer-intro {
  margin: 0;
  max-width: 40ch;
  font-size: var(--step-sm);
  line-height: 1.8;
  color: var(--on-dark-mute);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--sp-6) var(--sp-5);
  padding-block: clamp(28px, 3.4vw, 46px);
}

.footer-group-title {
  margin: 0 0 var(--sp-4);
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  font-weight: 400;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.footer-links {
  display: grid;
  gap: var(--sp-2);
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-link {
  display: inline-block;
  color: var(--white);
  font-size: var(--step-sm);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--tick) linear, border-color var(--tick) linear;
}
.footer-link:hover,
.footer-link:focus-visible {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
  text-decoration: none;
}

/* 第二层：联系与备案 */
.footer-legal {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
  gap: var(--sp-6);
  padding-block: clamp(24px, 3vw, 40px);
  border-top: 1px solid var(--line-soft);
}

.contact-list {
  display: grid;
  gap: var(--sp-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.contact-item {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-3);
  font-size: var(--step-sm);
  line-height: 1.7;
}

.contact-label {
  flex: 0 0 auto;
  width: 46px;
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.14em;
  color: var(--silver);
}

.contact-value {
  color: rgba(248, 249, 248, 0.88);
  word-break: break-word;
}

.contact-item--wide { align-items: flex-start; }

.copy-btn {
  appearance: none;
  flex: 0 0 auto;
  padding: 4px 10px;
  border: 1px solid rgba(0, 224, 198, 0.5);
  border-radius: var(--radius);
  background: transparent;
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: background-color var(--tick) linear, color var(--tick) linear, border-color var(--tick) linear;
}
.copy-btn:hover { background: rgba(0, 224, 198, 0.14); }
.copy-btn.is-copied {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--navy-deep);
}

.legal-list {
  display: grid;
  gap: var(--sp-2);
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: var(--step-sm);
}

.legal-text {
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.08em;
  color: var(--silver);
}

/* 第三层：口号、年份与刻度线 */
.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--line-soft);
}

.footer-slogan {
  margin: 0;
  font-family: var(--font-title);
  font-size: var(--step-lg);
  font-weight: 900;
  letter-spacing: 0.16em;
  color: var(--white);
}

.footer-copy {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--step-xs);
  letter-spacing: 0.08em;
  color: rgba(248, 249, 248, 0.48);
}

.footer-scale {
  height: 10px;
  margin-top: var(--sp-5);
  background-image: repeating-linear-gradient(
    90deg,
    var(--cyan) 0 2px,
    transparent 2px 14px
  );
  opacity: 0.55;
}

/* ============================================================
   平板
   ============================================================ */
@media (max-width: 1024px) {
  :root { --gutter: 18px; }

  .header-rail { padding-block: 12px; }

  .header-inner {
    flex-wrap: wrap;
    row-gap: 10px;
    min-height: 0;
    align-items: center;
  }

  .brand { order: 1; }
  .header-tools { order: 2; margin-left: auto; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    order: 3;
    flex: 1 0 100%;
    margin-left: 0;
    display: none;
  }

  .site-nav[data-open] {
    display: block;
    margin-top: 2px;
    padding-top: var(--sp-3);
    border-top: 1px solid var(--line-soft);
    animation: navOpen 200ms ease-out;
  }

  @keyframes navOpen {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: none; }
  }

  .nav-list {
    flex-wrap: nowrap;
    overflow-x: auto;
    gap: var(--sp-2);
    padding-bottom: var(--sp-3);
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
  }
  .nav-list::-webkit-scrollbar { height: 3px; }
  .nav-list::-webkit-scrollbar-thumb { background: rgba(0, 224, 198, 0.5); }

  .nav-link {
    border: 1px solid var(--line-soft);
    white-space: nowrap;
    padding: 9px 13px;
    font-size: var(--step-xs);
    letter-spacing: 0.08em;
  }
  .nav-list > li:last-child .nav-link { border-right: 1px solid var(--line-soft); }
  .nav-link::after { display: none; }
  .nav-link[aria-current="page"] { border-color: var(--cyan); }

  .col-side,
  .col-main,
  .col-main--edge,
  .col-note,
  .col-half { grid-column: 1 / -1; }

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

/* ============================================================
   手机
   ============================================================ */
@media (max-width: 720px) {
  body { font-size: 16px; }

  .brand-mark { font-size: 19px; letter-spacing: 0.1em; }
  .brand-tag { letter-spacing: 0.18em; }

  .device-switch { padding: 2px; }
  .device-btn { padding: 6px 8px; font-size: 10px; letter-spacing: 0.1em; }
  .nav-toggle-text { display: none; }
  .nav-toggle { padding: 9px 11px; }

  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--sp-5) var(--sp-4); }
  .footer-top { align-items: flex-start; }
  .footer-slogan { font-size: var(--step-md); letter-spacing: 0.12em; }
  .footer-base { justify-content: flex-start; }
  .contact-label { width: 100%; }
}

@media (max-width: 420px) {
  .footer-grid { grid-template-columns: 1fr; }
}

/* ============================================================
   动效收敛
   ============================================================ */
@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;
  }

  html.js [data-reveal] { opacity: 1; transform: none; }
  [data-reveal] { opacity: 1 !important; transform: none !important; }
  .read-progress-fill { transition: none !important; }
}