/* ============================================================
   KAIYUN体育 · 共享样式表 /assets/site.css
   夜场战术板：深墨绿黑场 + 奶油纸底 + 荧光青柠激活态 + 炽橙刻度
   ============================================================ */

/* ---------- 设计变量 ---------- */
:root {
  --ink-950: #03120E;
  --ink-900: #06231C;
  --ink-800: #0B3B2E;
  --paper-100: #F4EDDD;
  --paper-200: #E7DCC4;
  --lime: #B9FF3D;
  --lime-soft: #C9FF66;
  --lime-dim: #6F9A22;
  --orange: #FF6A2B;
  --steel: #8AA2B0;
  --brown: #1F1710;

  --font-display: "Songti SC", "Noto Serif CJK SC", "Source Han Serif SC", "SimSun", Georgia, serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Noto Sans CJK SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", ui-monospace, Menlo, Consolas, monospace;

  --r-lg: 26px;
  --r-md: 18px;
  --r-sm: 12px;
  --r-pill: 999px;

  --line-dark: rgba(185, 255, 61, 0.18);
  --line-cool: rgba(138, 162, 176, 0.28);
  --shadow-panel: 0 18px 48px rgba(3, 18, 14, 0.38);
  --header-h: 104px;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--brown);
  background: var(--paper-100);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6, p, ul, ol, dl, dd, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
img, svg, video { display: block; max-width: 100%; height: auto; }
table { border-collapse: collapse; width: 100%; }

/* ---------- 焦点与无障碍 ---------- */
:where(a, button, input, select, textarea, [tabindex]):focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 3px;
  box-shadow: 0 0 0 5px rgba(6, 35, 28, 0.5);
  border-radius: 6px;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: 12px;
  z-index: 999;
  padding: 10px 18px;
  border-radius: var(--r-pill);
  background: var(--lime);
  color: var(--ink-900);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(-180%);
  transition: transform 0.2s ease;
}
.skip-link:focus { transform: translateY(0); }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

/* ---------- 容器与栅格 ---------- */
.wrap {
  width: min(1240px, 100% - 48px);
  margin-inline: auto;
}

.grid { display: grid; gap: 24px; }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); }

.section { padding-block: clamp(56px, 8vw, 112px); }
.section--tight { padding-block: clamp(36px, 5vw, 64px); }
.section--paper { background: var(--paper-100); color: var(--brown); }
.section--dark { background: var(--ink-900); color: var(--paper-100); }
.section--band { background: var(--ink-800); color: var(--paper-100); }

.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: linear-gradient(90deg, rgba(138, 162, 176, 0.55), rgba(138, 162, 176, 0));
}

/* ---------- 排版 ---------- */
.display-1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(34px, 5vw, 68px);
  line-height: 1.1;
  letter-spacing: -0.01em;
}
.display-2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(26px, 3.4vw, 48px);
  line-height: 1.16;
  letter-spacing: -0.01em;
}
.display-3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(20px, 2.2vw, 26px);
  line-height: 1.3;
}

.meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--steel);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.prose { max-width: 46rem; font-size: 17px; line-height: 1.8; }
.prose p + p { margin-top: 1em; }
.prose h2,
.prose h3 { font-family: var(--font-display); margin: 1.6em 0 0.6em; line-height: 1.32; }
.prose h2 { font-size: clamp(22px, 2.4vw, 30px); }
.prose h3 { font-size: clamp(18px, 2vw, 22px); }
.prose ul,
.prose ol { margin: 1em 0; padding-left: 1.3em; }
.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: 0.4em; }
.prose a {
  text-decoration: underline;
  text-decoration-color: var(--lime-dim);
  text-underline-offset: 3px;
}
.prose a:hover { text-decoration-color: var(--orange); }
.prose blockquote {
  margin: 1.4em 0;
  padding: 14px 20px;
  border-left: 4px solid var(--lime);
  background: var(--paper-200);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.2;
  white-space: nowrap;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
}
.btn--sm { padding: 9px 18px; font-size: 14px; }
.btn--lime {
  background: var(--lime);
  color: var(--ink-900);
  box-shadow: 0 0 0 1px rgba(185, 255, 61, 0.35), 0 8px 22px rgba(185, 255, 61, 0.16);
}
.btn--lime:hover { background: var(--lime-soft); transform: translateY(-1px); }
.btn--ghost {
  border-color: rgba(185, 255, 61, 0.45);
  color: var(--lime);
  background: transparent;
}
.btn--ghost:hover { background: rgba(185, 255, 61, 0.12); }
.btn--dark {
  background: var(--ink-900);
  color: var(--paper-100);
  border-color: rgba(185, 255, 61, 0.22);
}
.btn--dark:hover { background: var(--ink-800); }

/* ---------- 标签与筛选胶囊 ---------- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--r-pill);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  border: 1px solid var(--line-cool);
  color: var(--steel);
}
.chip--lime {
  border-color: rgba(185, 255, 61, 0.5);
  color: var(--lime);
  background: rgba(185, 255, 61, 0.08);
}
.chip--orange {
  border-color: rgba(255, 106, 43, 0.5);
  color: var(--orange);
  background: rgba(255, 106, 43, 0.1);
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.filter-pill {
  padding: 8px 16px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line-cool);
  font-size: 13px;
  font-weight: 500;
  color: inherit;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}
.filter-pill:hover { border-color: var(--lime); color: var(--lime-dim); }
.filter-pill[aria-pressed="true"] {
  background: var(--lime);
  border-color: var(--lime);
  color: var(--ink-900);
  font-weight: 700;
}
[data-filter-item][hidden] { display: none !important; }

/* ---------- 章节头 ---------- */
.chapter-head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 3vw, 40px);
}
.chapter-num {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--orange);
}
.chapter-num::after {
  content: "";
  width: 56px;
  height: 1px;
  background: linear-gradient(90deg, var(--orange), rgba(255, 106, 43, 0));
}
.chapter-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(26px, 3.4vw, 48px);
  line-height: 1.15;
  letter-spacing: -0.01em;
  padding-left: 16px;
  border-left: 4px solid var(--lime);
}
.chapter-lead {
  padding-left: 20px;
  max-width: 46em;
  font-size: 16px;
  opacity: 0.84;
}

/* ---------- 卡片与指标 ---------- */
.card {
  padding: 22px;
  border-radius: var(--r-md);
  background: var(--paper-200);
  border: 1px solid rgba(31, 23, 16, 0.1);
}
.card--dark {
  background: var(--ink-800);
  border-color: rgba(185, 255, 61, 0.2);
  color: var(--paper-100);
}

.stat { display: grid; gap: 6px; }
.stat__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(28px, 3.6vw, 44px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--lime);
}
.stat__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--steel);
}

/* ---------- 时间轴 ---------- */
.timeline {
  position: relative;
  padding-left: 26px;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, rgba(185, 255, 61, 0.7), rgba(138, 162, 176, 0.22));
}
.timeline__item { position: relative; padding-bottom: 26px; }
.timeline__item:last-child { padding-bottom: 0; }
.timeline__item::before {
  content: "";
  position: absolute;
  left: -26px;
  top: 8px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 1px solid var(--steel);
  background: transparent;
}
.timeline__item[data-current="true"]::before {
  border-color: var(--lime);
  background: var(--lime);
  box-shadow: 0 0 0 4px rgba(185, 255, 61, 0.16);
}

/* ---------- 横向数据带 ---------- */
.band-scroll {
  display: flex;
  gap: 14px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  padding-block: 6px;
  scrollbar-width: thin;
}
.band-scroll > * { flex: 0 0 clamp(190px, 24vw, 260px); scroll-snap-align: start; }

/* ---------- 图片容器 ---------- */
.figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border-radius: var(--r-lg);
  background: var(--ink-800);
  border: 1px solid var(--line-dark);
}
.figure__media {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  filter: saturate(1.02) contrast(1.08) brightness(0.88);
}
.figure--portrait .figure__media { aspect-ratio: 4 / 5; }
.figure--wide .figure__media { aspect-ratio: 21 / 9; }
.figure__media--placeholder {
  display: grid;
  place-items: center;
  background:
    repeating-linear-gradient(135deg, rgba(185, 255, 61, 0.07) 0 12px, transparent 12px 24px),
    var(--ink-800);
  color: rgba(138, 162, 176, 0.85);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.figure__caption {
  padding: 12px 18px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: rgba(244, 237, 221, 0.72);
  background: rgba(3, 18, 14, 0.86);
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 18px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--steel);
}
.breadcrumb a { transition: color 0.18s ease; }
.breadcrumb a:hover { color: var(--lime-dim); }
.breadcrumb__sep { color: rgba(138, 162, 176, 0.55); }
.breadcrumb [aria-current="page"] { color: var(--brown); font-weight: 600; }
.section--dark .breadcrumb,
.section--band .breadcrumb { color: rgba(244, 237, 221, 0.62); }
.section--dark .breadcrumb [aria-current="page"],
.section--band .breadcrumb [aria-current="page"] { color: var(--paper-100); }

/* ---------- 显现动画 ---------- */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
html.js [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

/* ============================================================
   头部
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 300;
  color: var(--paper-100);
  background: linear-gradient(180deg, #08291F 0%, var(--ink-900) 100%);
  border-bottom: 1px solid var(--line-dark);
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}
.site-header[data-compact="true"] {
  box-shadow: 0 14px 34px rgba(3, 18, 14, 0.5);
  border-bottom-color: rgba(185, 255, 61, 0.3);
}

/* 上层署名带 */
.header-top {
  max-height: 60px;
  overflow: hidden;
  border-bottom: 1px solid rgba(138, 162, 176, 0.16);
  transition: max-height 0.34s ease, opacity 0.24s ease, border-color 0.24s ease;
}
.site-header[data-compact="true"] .header-top {
  max-height: 0;
  opacity: 0;
  border-bottom-color: transparent;
}
.header-top__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 40px;
  padding-block: 8px;
}
.top-sign {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}
.top-sign__brand {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--lime);
  white-space: nowrap;
}
.top-sign__sep {
  width: 22px;
  height: 1px;
  background: rgba(138, 162, 176, 0.55);
  flex: none;
}
.top-sign__line {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: rgba(244, 237, 221, 0.7);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.top-meta {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  flex: none;
}
.top-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: rgba(244, 237, 221, 0.74);
}
.top-status__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 0 3px rgba(185, 255, 61, 0.18);
  flex: none;
}
.top-mail {
  padding: 4px 12px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(185, 255, 61, 0.35);
  font-size: 12px;
  color: var(--lime);
  transition: background-color 0.18s ease, color 0.18s ease;
}
.top-mail:hover { background: var(--lime); color: var(--ink-900); }

/* 主行 */
.header-nav { padding-block: 12px; }
.header-nav__inner {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 0;
  border: 1px solid transparent;
  transition: background-color 0.3s ease, border-color 0.3s ease,
    border-radius 0.3s ease, padding 0.3s ease, box-shadow 0.3s ease;
}
.site-header[data-compact="true"] .header-nav { padding-block: 8px; }
.site-header[data-compact="true"] .header-nav__inner {
  padding: 6px 8px 6px 16px;
  border-radius: var(--r-pill);
  border-color: rgba(185, 255, 61, 0.22);
  background: rgba(3, 18, 14, 0.9);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 12px 30px rgba(3, 18, 14, 0.5);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: none;
}
.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--lime);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.02em;
  flex: none;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--paper-100);
}
.brand__sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--steel);
}

/* 主导航 */
.nav { flex: 1 1 auto; min-width: 0; }
.nav__list { display: flex; align-items: center; gap: 2px; flex-wrap: wrap; }
.nav__item { display: block; }
.nav__link {
  display: inline-block;
  padding: 9px 15px;
  border-radius: var(--r-pill);
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  color: rgba(244, 237, 221, 0.82);
  transition: background-color 0.18s ease, color 0.18s ease;
}
.nav__link:hover { background: rgba(185, 255, 61, 0.12); color: var(--lime); }
.nav__link[aria-current="page"] {
  background: var(--lime);
  color: var(--ink-900);
  font-weight: 700;
}

/* 右侧读数区 */
.nav-side {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-left: auto;
  flex: none;
}
.nav-readout {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--steel);
}
.nav-readout__label { color: rgba(138, 162, 176, 0.8); }
.nav-readout__chapter {
  padding: 1px 7px;
  border-radius: 6px;
  border: 1px solid rgba(255, 106, 43, 0.45);
  color: var(--orange);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.nav-readout__track {
  display: inline-block;
  width: 78px;
  height: 3px;
  border-radius: var(--r-pill);
  background: rgba(138, 162, 176, 0.26);
  overflow: hidden;
}
.nav-readout__track i {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--lime), var(--orange));
  transition: width 0.12s linear;
}

.header-cta { flex: none; }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(185, 255, 61, 0.35);
  color: var(--lime);
  font-size: 13px;
  flex: none;
}
.nav-toggle__icon { display: grid; gap: 3px; width: 16px; flex: none; }
.nav-toggle__icon span {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.2s ease, opacity 0.2s ease;
}
.site-header[data-open="true"] .nav-toggle__icon span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.site-header[data-open="true"] .nav-toggle__icon span:nth-child(2) { opacity: 0; }
.site-header[data-open="true"] .nav-toggle__icon span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }
.nav-toggle__text { letter-spacing: 0.06em; }

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  position: relative;
  padding-block: 64px 28px;
  background: var(--ink-950);
  color: rgba(244, 237, 221, 0.78);
  border-top: 1px solid rgba(185, 255, 61, 0.14);
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--lime), rgba(185, 255, 61, 0) 42%, rgba(255, 106, 43, 0.9));
}
.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.8fr) minmax(0, 0.8fr) minmax(0, 1.2fr);
  gap: 40px 32px;
}
.footer-brand { display: inline-flex; align-items: center; gap: 10px; }
.footer-brand__mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 9px;
  background: var(--lime);
  color: var(--ink-900);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  flex: none;
}
.footer-brand__name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--paper-100);
}
.footer-desc {
  margin-top: 16px;
  max-width: 32em;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(244, 237, 221, 0.72);
}
.footer-seal {
  display: inline-block;
  margin-top: 14px;
  padding: 5px 12px;
  border-radius: var(--r-pill);
  border: 1px dashed rgba(185, 255, 61, 0.42);
  color: var(--lime);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.footer-title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--steel);
}
.footer-list { display: grid; gap: 10px; }
.footer-link {
  font-size: 14px;
  color: rgba(244, 237, 221, 0.78);
  transition: color 0.18s ease;
}
.footer-link:hover { color: var(--lime); }
.contact-list { display: grid; gap: 12px; }
.contact-row {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  font-size: 14px;
}
.contact-row dt {
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--steel);
}
.contact-row dd {
  margin: 0;
  color: rgba(244, 237, 221, 0.9);
  word-break: break-word;
}
.footer-hint {
  margin-top: 14px;
  max-width: 30em;
  font-size: 12px;
  line-height: 1.7;
  color: rgba(138, 162, 176, 0.88);
}
.footer-base {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px 24px;
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid rgba(138, 162, 176, 0.18);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--steel);
}
.footer-copy { margin: 0; }
.footer-legal { margin: 0; }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1100px) {
  .nav-readout { display: none; }
  .nav__link { padding: 9px 12px; font-size: 13.5px; }
}

@media (max-width: 1000px) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 36px 28px;
  }
  .grid--split { grid-template-columns: 1fr; }
}

@media (max-width: 900px) {
  :root { --header-h: 76px; }
  .wrap { width: min(1240px, 100% - 40px); }
  .nav-toggle { display: inline-flex; }
  .header-nav__inner { flex-wrap: wrap; gap: 12px; }
  .site-header[data-compact="true"] .header-nav__inner {
    padding: 8px 10px;
    border-radius: var(--r-md);
  }
  .brand { order: 1; }
  .nav-side { order: 2; gap: 10px; }
  .nav {
    order: 3;
    flex-basis: 100%;
    display: none;
  }
  .site-header[data-open="true"] .nav { display: block; }
  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding-top: 10px;
    border-top: 1px solid rgba(138, 162, 176, 0.2);
  }
  .nav__link { display: block; padding: 11px 16px; border-radius: 14px; font-size: 15px; }
  .grid--2,
  .grid--3 { grid-template-columns: 1fr; }
  .section { padding-block: clamp(44px, 9vw, 78px); }
  .chapter-title { padding-left: 12px; }
  .chapter-lead { padding-left: 16px; }
}

@media (max-width: 720px) {
  .top-sign__line { display: none; }
  .top-status { display: none; }
  .header-top__inner { min-height: 34px; }
}

@media (max-width: 640px) {
  body { font-size: 16px; }
  .wrap { width: min(1240px, 100% - 32px); }
  .brand__sub { display: none; }
  .header-cta { padding: 8px 14px; font-size: 13px; }
  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .site-footer { padding-block: 48px 24px; }
  .footer-base { margin-top: 32px; flex-direction: column; }
}

@media (max-width: 480px) {
  .brand__text { display: none; }
  .nav-toggle__text { display: none; }
  .top-sign__sep { display: none; }
}

/* ---------- 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;
  }
  html.js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
  .nav-readout__track i { transition: none !important; }
}