/* =========================================================
   云开平台 · 全站赛事入口
   共享样式 /assets/site.css
   ========================================================= */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  background-color: #070C1C;
}

body,
h1, h2, h3, h4, h5, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

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

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

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

a { color: inherit; }

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

/* ---------- 2. 变量 ---------- */
:root {
  --bg: #070C1C;
  --layer: #0E1730;
  --glass-solid: #16244A;
  --glass: rgba(22, 36, 74, 0.66);

  --cyan: #3FE0D0;
  --orange: #FF7A2F;
  --violet: #7A5CFF;
  --blue: #2E7BFF;
  --green: #35C789;

  --text: #D7DEF0;
  --muted: #8C99BC;
  --line: #24325A;

  --rail-w: 244px;
  --topbar-h: 64px;
  --radius: 16px;
  --radius-sm: 10px;

  --font-display: "Oswald", "Archivo Narrow", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", "JetBrains Mono", "Roboto Mono", "Noto Sans Mono", Menlo, Consolas, monospace;

  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 底座与中文排版 ---------- */
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0.01em;
  color: var(--text);
  background-color: transparent;
  min-height: 100vh;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    radial-gradient(880px 560px at 88% -12%, rgba(63, 224, 208, 0.10), transparent 62%),
    radial-gradient(720px 520px at 4% 6%, rgba(122, 92, 255, 0.13), transparent 64%),
    radial-gradient(700px 620px at 54% 118%, rgba(46, 123, 255, 0.09), transparent 62%),
    linear-gradient(to right, rgba(36, 50, 90, 0.50) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(36, 50, 90, 0.50) 1px, transparent 1px);
  background-size: auto, auto, auto, 72px 72px, 72px 72px;
  -webkit-mask-image: radial-gradient(145% 110% at 50% 0%, #000 32%, rgba(0, 0, 0, 0.34) 100%);
  mask-image: radial-gradient(145% 110% at 50% 0%, #000 32%, rgba(0, 0, 0, 0.34) 100%);
}

p { max-width: 74ch; }
p + p { margin-top: 1em; }

strong { color: #FFFFFF; font-weight: 600; }

a { text-decoration-color: rgba(63, 224, 208, 0.45); text-underline-offset: 3px; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 6px;
}

::selection { background: rgba(63, 224, 208, 0.28); color: #FFFFFF; }

/* ---------- 4. 跳到主内容 ---------- */
.skip-link {
  position: fixed;
  top: 0;
  left: 50%;
  z-index: 400;
  padding: 12px 22px;
  border-radius: 0 0 12px 12px;
  background: var(--cyan);
  color: #04121A;
  font: 600 13px/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-decoration: none;
  transform: translate(-50%, -140%);
  transition: transform 0.2s var(--ease);
}

.skip-link:focus {
  transform: translate(-50%, 0);
}

#main-content { scroll-margin-top: 84px; }

/* ---------- 5. 侧轨页头 ---------- */
.site-header {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 120;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  gap: 26px;
  padding: 30px 20px 24px;
  background: rgba(20, 33, 68, 0.76);
  -webkit-backdrop-filter: blur(20px) saturate(140%);
  backdrop-filter: blur(20px) saturate(140%);
  color: var(--text);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
}

.site-header::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 1px;
  height: 100%;
  pointer-events: none;
  background: linear-gradient(to bottom,
    transparent 0%,
    rgba(63, 224, 208, 0.55) 16%,
    rgba(122, 92, 255, 0.40) 58%,
    transparent 100%);
}

.rail-progress {
  --p: 0%;
  position: absolute;
  top: 0;
  right: 0;
  width: 2px;
  height: var(--p);
  background: linear-gradient(to bottom, var(--cyan), var(--violet));
  box-shadow: 0 0 12px rgba(63, 224, 208, 0.55);
  pointer-events: none;
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
  flex: none;
}

.brand-mark {
  position: relative;
  width: 34px;
  height: 34px;
  flex: none;
  border-radius: 11px;
  background: conic-gradient(from 210deg, var(--cyan), var(--violet) 52%, var(--blue) 74%, var(--cyan));
  box-shadow: 0 0 0 1px rgba(63, 224, 208, 0.30), 0 10px 26px -10px rgba(63, 224, 208, 0.6);
}

.brand-mark::after {
  content: "";
  position: absolute;
  inset: 30%;
  border-radius: 4px;
  background: #070C1C;
}

.brand-text { display: block; min-width: 0; }

.brand-name {
  display: block;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: 0.04em;
  color: #FFFFFF;
}

.brand-subline {
  display: block;
  font: 400 11px/1.5 var(--font-mono);
  letter-spacing: 0.16em;
  color: var(--muted);
}

/* 移动端菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 13px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(22, 36, 74, 0.72);
  color: var(--text);
  font: 500 12px/1 var(--font-mono);
  letter-spacing: 0.12em;
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.nav-toggle-bars { display: grid; gap: 4px; width: 18px; }

.nav-toggle-bars i {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.18s var(--ease), opacity 0.18s var(--ease);
}

.nav-toggle[aria-expanded="true"] {
  color: var(--cyan);
  border-color: rgba(63, 224, 208, 0.55);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* 导航 */
.site-nav {
  display: flex;
  flex-direction: column;
  gap: 18px;
  flex: 1 1 auto;
  min-height: 0;
}

.nav-index-label {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  max-width: none;
  font: 400 11px/1 var(--font-mono);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}

.nav-index-label::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(to right, var(--line), transparent);
}

.nav-list {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.nav-link {
  display: flex;
  align-items: baseline;
  gap: 11px;
  padding: 11px 12px;
  border-radius: var(--radius-sm);
  border-left: 2px solid transparent;
  text-decoration: none;
  color: var(--text);
  font-size: 15px;
  line-height: 1.4;
  transition: background 0.16s var(--ease), color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.nav-link:hover {
  background: rgba(63, 224, 208, 0.08);
  color: #FFFFFF;
  border-left-color: rgba(63, 224, 208, 0.45);
}

.nav-link[aria-current="page"] {
  background: linear-gradient(90deg, rgba(63, 224, 208, 0.18), rgba(63, 224, 208, 0));
  border-left-color: var(--cyan);
  color: var(--cyan);
}

.nav-num {
  flex: none;
  font: 400 11px/1 var(--font-mono);
  letter-spacing: 0.08em;
  color: var(--muted);
}

.nav-link:hover .nav-num { color: rgba(63, 224, 208, 0.8); }
.nav-link[aria-current="page"] .nav-num { color: var(--cyan); }

.nav-label { min-width: 0; }

/* 侧轨底部 */
.nav-foot {
  margin-top: auto;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.nav-status {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: none;
  font: 400 11px/1.6 var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--muted);
}

.status-dot {
  flex: none;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 3px rgba(53, 199, 137, 0.18);
}

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

.to-top {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  align-self: flex-start;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font: 500 12px/1 var(--font-mono);
  letter-spacing: 0.1em;
  color: var(--muted);
  border: 1px solid transparent;
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease), color 0.2s var(--ease), visibility 0.2s;
}

.to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.to-top:hover {
  color: var(--cyan);
  border-color: rgba(63, 224, 208, 0.4);
}

.to-top-arrow { font-size: 14px; line-height: 1; }

/* ---------- 6. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 116px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(22, 36, 74, 0.55) 0%, rgba(7, 12, 28, 0.94) 100%);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(440px, 58%);
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), rgba(122, 92, 255, 0.5) 55%, transparent);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 48px);
  padding: clamp(44px, 6vw, 76px) clamp(20px, 4vw, 56px) clamp(28px, 4vw, 44px);
  max-width: 1240px;
  margin: 0 auto;
}

.footer-brand { display: flex; flex-direction: column; gap: 16px; align-items: flex-start; }

.footer-tagline {
  max-width: 34ch;
  font: 400 13px/1.7 var(--font-mono);
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.footer-note {
  max-width: 40ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted);
}

.footer-col { display: flex; flex-direction: column; }

.footer-col-title {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
  font: 400 11px/1 var(--font-mono);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}

.footer-col-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(to right, var(--line), transparent);
}

.footer-links { display: flex; flex-direction: column; gap: 10px; }

.footer-links a {
  position: relative;
  display: inline-block;
  font-size: 15px;
  text-decoration: none;
  color: var(--text);
  padding-left: 0;
  transition: color 0.16s var(--ease), padding-left 0.16s var(--ease);
}

.footer-links a::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 0;
  height: 1px;
  background: var(--cyan);
  transition: width 0.16s var(--ease);
}

.footer-links a:hover { color: var(--cyan); padding-left: 16px; }
.footer-links a:hover::before { width: 11px; }

.footer-contact { display: flex; flex-direction: column; gap: 14px; }

.footer-contact li { display: grid; gap: 3px; }

.footer-contact-key {
  font: 400 11px/1.5 var(--font-mono);
  letter-spacing: 0.14em;
  color: var(--muted);
}

.footer-contact .mono { color: var(--text); font-size: 14px; word-break: break-all; }
.footer-contact span:not(.footer-contact-key) { font-size: 14px; line-height: 1.65; color: var(--text); }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  max-width: 1240px;
  margin: 0 auto;
  padding: 20px clamp(20px, 4vw, 56px) 30px;
  border-top: 1px solid var(--line);
  font: 400 12px/1.7 var(--font-mono);
  letter-spacing: 0.05em;
  color: var(--muted);
}

.footer-legal p { max-width: none; }
.footer-icp { color: var(--muted); }

.footer-legal-links { display: flex; flex-wrap: wrap; gap: 18px; }

.footer-legal-links a { text-decoration: none; color: var(--muted); transition: color 0.16s var(--ease); }
.footer-legal-links a:hover { color: var(--cyan); }

/* ---------- 7. 容器与栅格 ---------- */
.container {
  width: 100%;
  max-width: 1240px;
  margin: 0 auto;
  padding-left: clamp(20px, 4vw, 56px);
  padding-right: clamp(20px, 4vw, 56px);
}

.container--wide { max-width: 1480px; }
.container--narrow { max-width: 820px; }

.split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(24px, 4vw, 56px);
}

.grid { display: grid; gap: clamp(16px, 2vw, 28px); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.grid-4 { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }

/* ---------- 8. 章节骨架 ---------- */
.section { padding: clamp(52px, 7vw, 104px) 0; }
.section--narrow { padding: clamp(32px, 4.5vw, 60px) 0; }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 16px;
  padding-bottom: 16px;
  margin-bottom: clamp(24px, 3vw, 40px);
  border-bottom: 1px solid var(--line);
}

.section-num {
  font: 400 12px/1 var(--font-mono);
  letter-spacing: 0.18em;
  color: var(--cyan);
}

.section-title {
  font-family: var(--font-display);
  font-weight: 250;
  font-size: clamp(22px, 2.6vw, 34px);
  line-height: 1.2;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: #FFFFFF;
}

.section-aside {
  margin-left: auto;
  font: 400 12px/1.6 var(--font-mono);
  letter-spacing: 0.08em;
  color: var(--muted);
  max-width: none;
}

.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: linear-gradient(90deg,
    rgba(63, 224, 208, 0.55) 0%,
    rgba(122, 92, 255, 0.35) 42%,
    transparent 100%);
}

/* ---------- 9. 正文开场（无 Hero） ---------- */
.page-intro { padding: clamp(40px, 6vw, 88px) 0 clamp(24px, 3.5vw, 44px); }

.page-eyebrow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
  max-width: none;
  font: 400 11px/1 var(--font-mono);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-eyebrow::after {
  content: "";
  flex: 1;
  min-width: 40px;
  height: 1px;
  background: linear-gradient(to right, var(--line), transparent);
}

.page-title {
  font-family: var(--font-display);
  font-weight: 200;
  font-size: clamp(40px, 7vw, 96px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  text-transform: uppercase;
  color: #FFFFFF;
  margin-bottom: 22px;
  overflow-wrap: anywhere;
}

.page-lede {
  max-width: 68ch;
  font-size: 17px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 10. 面板 / 卡片 ---------- */
.panel {
  background: var(--layer);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(20px, 2.4vw, 32px);
}

.panel--glass {
  background: var(--glass);
  -webkit-backdrop-filter: blur(16px) saturate(130%);
  backdrop-filter: blur(16px) saturate(130%);
}

.panel--glow {
  border-color: rgba(63, 224, 208, 0.30);
  box-shadow: 0 0 0 1px rgba(63, 224, 208, 0.10), 0 22px 60px -32px rgba(63, 224, 208, 0.55);
}

.panel-title {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(17px, 1.7vw, 21px);
  letter-spacing: 0.02em;
  color: #FFFFFF;
  margin-bottom: 10px;
}

.panel-text { font-size: 15px; line-height: 1.8; color: var(--muted); }

/* ---------- 11. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: border-color 0.16s var(--ease), color 0.16s var(--ease),
              background 0.16s var(--ease), transform 0.16s var(--ease);
}

.btn:active { transform: translateY(1px); }

.btn-primary {
  background: linear-gradient(120deg, var(--cyan) 0%, #55B8FF 100%);
  color: #04121A;
}

.btn-primary:hover { box-shadow: 0 14px 34px -16px rgba(63, 224, 208, 0.9); }

.btn-accent {
  background: linear-gradient(120deg, var(--orange) 0%, #FFB05C 100%);
  color: #1A0800;
}

.btn-accent:hover { box-shadow: 0 14px 34px -16px rgba(255, 122, 47, 0.9); }

.btn-ghost {
  background: rgba(22, 36, 74, 0.62);
  border-color: var(--line);
  color: var(--text);
}

.btn-ghost:hover {
  border-color: rgba(63, 224, 208, 0.6);
  color: var(--cyan);
}

/* ---------- 12. 标签与索引 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--line);
  font: 400 12px/1.6 var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--muted);
}

.tag--live {
  border-color: rgba(63, 224, 208, 0.5);
  background: rgba(63, 224, 208, 0.08);
  color: var(--cyan);
}

.tag--soon {
  border-color: rgba(255, 122, 47, 0.5);
  background: rgba(255, 122, 47, 0.08);
  color: var(--orange);
}

.tag--done {
  border-color: rgba(53, 199, 137, 0.45);
  background: rgba(53, 199, 137, 0.08);
  color: var(--green);
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
}

.index-label {
  font: 400 12px/1 var(--font-mono);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ---------- 13. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-top: clamp(20px, 3vw, 34px);
  font: 400 12px/1.6 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

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

.breadcrumb li + li::before {
  content: "/";
  color: var(--line);
}

.breadcrumb a { text-decoration: none; color: var(--muted); transition: color 0.16s var(--ease); }
.breadcrumb a:hover { color: var(--cyan); }
.breadcrumb [aria-current="page"] { color: var(--text); }

/* ---------- 14. 响应式图片容器 ---------- */
.figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--layer);
}

.figure > img,
.figure > picture,
.figure > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure--16x9 { aspect-ratio: 16 / 9; }
.figure--4x3 { aspect-ratio: 4 / 3; }
.figure--1x1 { aspect-ratio: 1 / 1; }
.figure--wide { aspect-ratio: 21 / 9; }

.figure--mesh {
  background-image:
    linear-gradient(135deg, rgba(122, 92, 255, 0.22) 0%, rgba(46, 123, 255, 0.14) 48%, rgba(63, 224, 208, 0.10) 100%);
  background-color: var(--layer);
}

.figure--mesh::after {
  content: attr(data-label);
  position: absolute;
  left: 18px;
  bottom: 16px;
  font: 400 11px/1.6 var(--font-mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(215, 222, 240, 0.72);
}

.figure-caption {
  margin-top: 10px;
  font: 400 12px/1.7 var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 15. 显现动效 ---------- */
.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
}

.reveal-ready [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 16. 断点：桌面侧轨 ---------- */
@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }

  .split { grid-template-columns: minmax(200px, 3fr) minmax(0, 9fr); }
  .split--flip { grid-template-columns: minmax(0, 9fr) minmax(200px, 3fr); }

  .footer-grid { grid-template-columns: 1.5fr 1fr 1fr 1.4fr; }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* ---------- 17. 断点：移动端抽屉 ---------- */
@media (max-width: 1023px) {
  #main-content { padding-top: var(--topbar-h); }

  .site-header {
    inset: 0 0 auto 0;
    width: auto;
    height: var(--topbar-h);
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    padding: 0 clamp(14px, 4vw, 22px);
    border-bottom: 1px solid var(--line);
    border-right: 0;
    overflow: visible;
  }

  .site-header::after { display: none; }

  .rail-progress {
    top: auto;
    bottom: -1px;
    right: auto;
    left: 0;
    width: var(--p);
    height: 2px;
    background: linear-gradient(to right, var(--cyan), var(--violet));
  }

  .brand-mark { width: 28px; height: 28px; border-radius: 9px; }
  .brand-name { font-size: 14px; }
  .brand-subline { display: none; }

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

  .site-nav {
    position: fixed;
    top: var(--topbar-h);
    left: 0;
    bottom: 0;
    width: min(86vw, 340px);
    z-index: 5;
    padding: 24px 20px 32px;
    gap: 20px;
    background: rgba(11, 19, 42, 0.97);
    -webkit-backdrop-filter: blur(18px);
    backdrop-filter: blur(18px);
    border-right: 1px solid var(--line);
    overflow-y: auto;
    overscroll-behavior: contain;
    transform: translateX(-102%);
    visibility: hidden;
    transition: transform 0.24s var(--ease), visibility 0.24s var(--ease);
  }

  .site-nav[data-open] {
    transform: none;
    visibility: visible;
  }

  body.nav-open::after {
    content: "";
    position: fixed;
    inset: var(--topbar-h) 0 0 0;
    z-index: 110;
    background: rgba(7, 12, 28, 0.72);
    -webkit-backdrop-filter: blur(3px);
    backdrop-filter: blur(3px);
  }

  .to-top { align-self: stretch; justify-content: center; }

  .page-title { font-size: clamp(34px, 11vw, 62px); }
}

@media (max-width: 560px) {
  .footer-legal { flex-direction: column; align-items: flex-start; }
  .section-aside { margin-left: 0; }
}

/* ---------- 18. 减少动效 ---------- */
@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;
  }

  .reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
  }
}