/* =========================================================
   爱游戏赛场 · /assets/site.css
   共享外壳：reset / 变量 / 排版 / 页头 / 页脚 / 基础组件
   ========================================================= */

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

html {
  background: var(--ink-950);
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body, h1, h2, h3, h4, p, figure, blockquote, ul, ol, dl, dd, pre { margin: 0; }
ul[class], ol[class] { list-style: none; padding: 0; }
img, svg, video, canvas { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }

:root {
  /* ---- 色板 ---- */
  --ink-950: #040E18;
  --ink-900: #061525;
  --ink-800: #0D2740;
  --ink-700: #143A5C;
  --cyan: #27E6F5;
  --cyan-glow: #8AF7FF;
  --orange: #FF8A2A;
  --lime: #B8FF5A;
  --rock: #6D7B86;
  --sand: #F3EFE4;
  --clay: #B9684E;
  --white: #FFFFFF;

  --text: #DCE6EE;
  --text-soft: #A9B9C6;
  --text-dim: #8698A6;
  --line: rgba(109,123,134,.30);
  --line-soft: rgba(109,123,134,.16);
  --line-cyan: rgba(39,230,245,.36);

  /* ---- 字体 ---- */
  --font-display: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-serif: "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  /* ---- 形状 ---- */
  --r-xs: 8px;
  --r-sm: 14px;
  --r-md: 22px;
  --r-lg: 32px;
  --r-xl: 44px;
  --r-pill: 999px;

  /* ---- 尺度 ---- */
  --shell-max: 1240px;
  --shell: min(var(--shell-max), calc(100% - 2.6rem));
  --ease: cubic-bezier(.22,.61,.36,1);
  --dur: 200ms;
  --shadow-float: 0 20px 50px -26px rgba(0,0,0,.95);
}

body {
  position: relative;
  min-height: 100vh;
  background: transparent;
  color: var(--text);
  font-family: var(--font-body);
  font-size: clamp(1rem, .955rem + .2vw, 1.0625rem);
  font-weight: 400;
  line-height: 1.8;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* 全局氛围层：斜向光晕 + 数据网格 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(1200px 620px at 88% -12%, rgba(39,230,245,.13), transparent 64%),
    radial-gradient(900px 540px at -12% 6%, rgba(255,138,42,.09), transparent 62%),
    radial-gradient(760px 500px at 50% 108%, rgba(184,255,90,.06), transparent 70%),
    linear-gradient(180deg, #061525 0%, #040E18 100%);
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(109,123,134,.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(109,123,134,.06) 1px, transparent 1px);
  background-size: 92px 92px;
  -webkit-mask-image: radial-gradient(130% 92% at 50% 0%, #000 18%, transparent 78%);
  mask-image: radial-gradient(130% 92% at 50% 0%, #000 18%, transparent 78%);
  opacity: .9;
}

/* ---------------- 中文排版与基础文字 ---------------- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -.015em;
  color: var(--sand);
  text-wrap: balance;
}

h1 { font-size: clamp(2.1rem, 1.4rem + 3.4vw, 3.6rem); font-weight: 900; }
h2 { font-size: clamp(1.6rem, 1.2rem + 1.9vw, 2.5rem); }
h3 { font-size: clamp(1.18rem, 1.05rem + .7vw, 1.5rem); font-weight: 700; }

p { text-wrap: pretty; }

strong, b { font-weight: 700; color: var(--sand); }

small { font-size: .85em; }

::selection {
  background: rgba(39,230,245,.32);
  color: var(--white);
}

/* ---------------- 可访问性 ---------------- */
:where(a, button, [tabindex]):focus-visible {
  outline: 2px solid var(--cyan-glow);
  outline-offset: 3px;
  border-radius: var(--r-xs);
}

.sr-only {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  inset-block-start: .6rem;
  inset-inline-start: .6rem;
  z-index: 300;
  display: inline-flex;
  align-items: center;
  padding: .62rem 1.15rem;
  border-radius: var(--r-pill);
  background: var(--cyan);
  color: var(--ink-950);
  font-weight: 800;
  font-size: .9rem;
  letter-spacing: .02em;
  box-shadow: 0 14px 34px -16px rgba(39,230,245,.9);
  transform: translateY(-180%);
  transition: transform .2s var(--ease);
}
.skip-link:focus-visible { transform: translateY(0); }

/* ---------------- 布局容器 ---------------- */
.shell {
  width: var(--shell);
  margin-inline: auto;
}
.shell--wide {
  width: min(1460px, calc(100% - 2rem));
  margin-inline: auto;
}
.shell--narrow {
  width: min(780px, calc(100% - 2.6rem));
  margin-inline: auto;
}

.grid {
  display: grid;
  gap: clamp(1rem, 2.4vw, 1.8rem);
}
.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, 1.35fr) minmax(0, 1fr); }

/* ---------------- 按钮 ---------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .45rem;
  min-block-size: 2.7rem;
  padding: .55rem 1.15rem;
  border: 1px solid transparent;
  border-radius: var(--r-pill);
  font-family: var(--font-display);
  font-size: .93rem;
  font-weight: 700;
  letter-spacing: .015em;
  line-height: 1.2;
  white-space: nowrap;
  cursor: pointer;
  transition: transform .18s var(--ease), background-color .18s var(--ease),
              color .18s var(--ease), border-color .18s var(--ease), box-shadow .18s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn-cta {
  background: linear-gradient(135deg, #FF8A2A 0%, #FFB066 100%);
  color: #1A0A00;
  box-shadow: 0 12px 28px -14px rgba(255,138,42,.95);
}
.btn-cta:hover { box-shadow: 0 16px 34px -14px rgba(255,138,42,1); }

.btn-cyan {
  background: linear-gradient(135deg, var(--cyan) 0%, var(--cyan-glow) 100%);
  color: var(--ink-950);
  box-shadow: 0 12px 28px -16px rgba(39,230,245,.95);
}

.btn-ghost {
  background: transparent;
  color: var(--sand);
  border-color: rgba(109,123,134,.5);
}
.btn-ghost:hover {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(39,230,245,.07);
}

/* ---------------- 标签 / 眉标 / 链接 ---------------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: .38rem;
  padding: .22rem .62rem;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--text-dim);
  line-height: 1.5;
}
.tag--cyan { color: var(--cyan); border-color: var(--line-cyan); background: rgba(39,230,245,.09); }
.tag--orange { color: var(--orange); border-color: rgba(255,138,42,.44); background: rgba(255,138,42,.1); }
.tag--lime { color: var(--lime); border-color: rgba(184,255,90,.44); background: rgba(184,255,90,.1); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan);
}
.eyebrow::before {
  content: "";
  inline-size: 1.7rem;
  block-size: 1px;
  background: currentColor;
  opacity: .85;
}

.link-more {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding-block-end: .15rem;
  border-block-end: 1px solid rgba(39,230,245,.35);
  color: var(--cyan);
  font-weight: 700;
  font-size: .92rem;
  transition: gap .18s var(--ease), border-color .18s var(--ease);
}
.link-more::after {
  content: "→";
  font-family: var(--font-mono);
  transition: transform .18s var(--ease);
}
.link-more:hover { gap: .7rem; border-color: var(--cyan); }

/* ---------------- 面包屑 ---------------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .2rem;
  padding: 0;
  margin: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--rock);
}
.crumbs li { display: inline-flex; align-items: center; }
.crumbs li:not(:last-child)::after {
  content: "/";
  margin-inline: .5rem;
  color: rgba(109,123,134,.55);
}
.crumbs a { color: var(--text-soft); }
.crumbs a:hover { color: var(--cyan); }

/* ---------------- 面板 ---------------- */
.panel {
  position: relative;
  padding: clamp(1.15rem, 2.4vw, 2rem);
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background:
    linear-gradient(158deg, rgba(13,39,64,.95) 0%, rgba(6,21,37,.92) 100%);
  box-shadow: var(--shadow-float);
}

/* ---------------- 图片容器（页面阶段放占位/媒体） ---------------- */
.frame {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background:
    radial-gradient(120% 90% at 100% 0%, rgba(39,230,245,.28), transparent 58%),
    radial-gradient(90% 80% at 0% 100%, rgba(255,138,42,.22), transparent 60%),
    linear-gradient(150deg, var(--ink-800) 0%, #071B2E 60%, #040E18 100%);
}
.frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(138,247,255,.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(138,247,255,.09) 1px, transparent 1px);
  background-size: 40px 40px;
  opacity: .55;
  pointer-events: none;
}
.frame::after {
  content: "";
  position: absolute;
  inset-block-start: -30%;
  inset-inline-start: -20%;
  inline-size: 60%;
  block-size: 160%;
  background: linear-gradient(100deg, transparent 0%, rgba(39,230,245,.16) 46%, transparent 100%);
  transform: rotate(12deg);
  pointer-events: none;
  transition: transform .6s var(--ease);
}
.frame:hover::after { transform: rotate(12deg) translateX(18%); }

.frame-media {
  position: relative;
  z-index: 1;
  inline-size: 100%;
  block-size: 100%;
  object-fit: cover;
}

.frame-tag {
  position: absolute;
  z-index: 2;
  inset-block-end: .8rem;
  inset-inline-start: .8rem;
}

.frame--wide { aspect-ratio: 16 / 7; }
.frame--card { aspect-ratio: 4 / 3; }
.frame--tall { aspect-ratio: 3 / 4; }
.frame--square { aspect-ratio: 1 / 1; }

/* ---------------- 正文排版容器 ---------------- */
.prose { max-width: 68ch; }
.prose > * + * { margin-block-start: 1.05em; }
.prose h2, .prose h3 { margin-block-start: 1.9em; }
.prose a {
  color: var(--cyan);
  border-block-end: 1px solid rgba(39,230,245,.35);
}
.prose a:hover { border-color: var(--cyan); }
.prose ul, .prose ol {
  padding-inline-start: 1.25rem;
  list-style: disc;
}
.prose ol { list-style: decimal; }
.prose li + li { margin-block-start: .4em; }
.prose blockquote {
  padding-inline-start: 1.1rem;
  border-inline-start: 2px solid var(--cyan);
  font-family: var(--font-serif);
  color: var(--sand);
  font-size: 1.08em;
}
.prose code {
  font-family: var(--font-mono);
  font-size: .9em;
  padding: .12em .42em;
  border-radius: var(--r-xs);
  background: rgba(39,230,245,.12);
  color: var(--cyan-glow);
}

/* =========================================================
   页头
   ========================================================= */
.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 90;
  padding-block-start: .9rem;
  transition: padding-block-start .24s var(--ease);
}
.site-header.is-condensed { padding-block-start: .35rem; }

.header-shell {
  position: relative;
  width: var(--shell);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .5rem .5rem .5rem 1rem;
  border: 1px solid rgba(109,123,134,.3);
  border-radius: var(--r-pill);
  background:
    linear-gradient(120deg, rgba(13,39,64,.94) 0%, rgba(6,21,37,.88) 100%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  box-shadow: var(--shadow-float), inset 0 1px 0 rgba(138,247,255,.08);
  transition: padding .24s var(--ease), box-shadow .24s var(--ease);
}
.site-header.is-condensed .header-shell {
  padding-block: .32rem;
  box-shadow: 0 14px 36px -24px rgba(0,0,0,.95), inset 0 1px 0 rgba(138,247,255,.1);
}

/* 顶部斜向扫描光带 */
.header-shell::after {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline-start: 30%;
  inline-size: 40%;
  block-size: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, transparent 0%, var(--cyan) 40%, var(--orange) 72%, transparent 100%);
  opacity: .5;
  animation: header-scan 6.5s var(--ease) infinite;
  pointer-events: none;
}
@keyframes header-scan {
  0%, 100% { transform: translateX(-18%); opacity: .3; }
  50% { transform: translateX(18%); opacity: .95; }
}

/* ---- 品牌 ---- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: .65rem;
  flex: 0 0 auto;
  padding-inline-end: .2rem;
}
.brand-mark {
  position: relative;
  inline-size: 2.15rem;
  block-size: 2.15rem;
  flex: 0 0 auto;
  border-radius: 12px;
  background: linear-gradient(140deg, var(--cyan) 0%, #0D2740 52%, var(--orange) 100%);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.2), 0 0 20px -8px var(--cyan);
  transition: transform .24s var(--ease);
}
.brand-mark::after {
  content: "";
  position: absolute;
  inset: 6px;
  border: 2px solid rgba(4,14,24,.88);
  border-block-start-color: transparent;
  border-inline-start-color: transparent;
  border-radius: 5px;
  transform: rotate(45deg);
}
.brand:hover .brand-mark { transform: rotate(-8deg) scale(1.04); }

.brand-text { display: flex; flex-direction: column; gap: .1rem; }
.brand-name {
  display: block;
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 800;
  letter-spacing: .02em;
  line-height: 1.2;
  color: var(--sand);
}
.brand-note {
  display: block;
  font-family: var(--font-mono);
  font-size: .62rem;
  font-weight: 500;
  letter-spacing: .13em;
  text-transform: uppercase;
  line-height: 1.3;
  color: var(--rock);
}

/* ---- 导航 ---- */
.nav-cluster { display: block; }
.nav-list {
  display: flex;
  align-items: center;
  gap: .1rem;
}
.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: .44rem .78rem;
  border-radius: var(--r-pill);
  font-family: var(--font-display);
  font-size: .9rem;
  font-weight: 600;
  letter-spacing: .01em;
  color: var(--text-soft);
  white-space: nowrap;
  transition: color .18s var(--ease), background-color .18s var(--ease), box-shadow .18s var(--ease);
}
.nav-link:hover {
  color: var(--sand);
  background: rgba(39,230,245,.1);
}
.nav-link[aria-current="page"] {
  color: var(--ink-950);
  background: linear-gradient(135deg, var(--cyan) 0%, var(--cyan-glow) 100%);
  box-shadow: 0 8px 22px -14px rgba(39,230,245,.95), inset 0 0 0 1px rgba(255,255,255,.28);
}
.nav-link[aria-current="page"]:hover { color: var(--ink-950); }

.nav-cta { display: none; }

/* ---- 右侧行动区 ---- */
.header-actions {
  display: flex;
  align-items: center;
  gap: .45rem;
  flex: 0 0 auto;
}
.header-cta { display: inline-flex; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: .5rem;
  padding: .5rem .9rem .5rem .72rem;
  border: 1px solid rgba(109,123,134,.45);
  border-radius: var(--r-pill);
  background: rgba(243,239,228,.06);
  color: var(--sand);
  font-family: var(--font-display);
  font-size: .86rem;
  font-weight: 700;
  cursor: pointer;
  transition: background-color .18s var(--ease), border-color .18s var(--ease), color .18s var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }
.nav-toggle[aria-expanded="true"] {
  background: rgba(39,230,245,.14);
  border-color: var(--line-cyan);
  color: var(--cyan);
}

.nav-toggle-icon {
  position: relative;
  display: block;
  inline-size: 1.05rem;
  block-size: .72rem;
  flex: 0 0 auto;
}
.nav-toggle-icon span {
  position: absolute;
  inset-inline: 0;
  block-size: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: inset-block-start .22s var(--ease), transform .22s var(--ease);
}
.nav-toggle-icon span:first-child { inset-block-start: 0; }
.nav-toggle-icon span:last-child { inset-block-start: calc(100% - 2px); }
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:first-child {
  inset-block-start: calc(50% - 1px);
  transform: rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:last-child {
  inset-block-start: calc(50% - 1px);
  transform: rotate(-45deg);
}
.nav-toggle-text { line-height: 1; }

/* ---- 阅读进度轨 ---- */
.scroll-meter {
  width: var(--shell);
  margin: .45rem auto 0;
  block-size: 2px;
  border-radius: 2px;
  background: rgba(109,123,134,.2);
  overflow: hidden;
}
.scroll-meter-fill {
  display: block;
  inline-size: 100%;
  block-size: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--lime) 62%, var(--orange) 100%);
  transform: scaleX(0);
  transform-origin: 0 50%;
}

/* =========================================================
   页脚
   ========================================================= */
.site-footer {
  position: relative;
  margin-block-start: clamp(2.6rem, 6vw, 4.5rem);
  padding-block: clamp(2.2rem, 5vw, 3.6rem) 1.3rem;
  border-block-start: 1px solid var(--line-soft);
  background:
    radial-gradient(880px 380px at 10% 0%, rgba(39,230,245,.1), transparent 64%),
    radial-gradient(620px 320px at 92% 8%, rgba(255,138,42,.08), transparent 68%),
    linear-gradient(180deg, rgba(6,21,37,0) 0%, #040E18 46%);
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute;
  inset-block-start: 0;
  inset-inline-start: 0;
  inline-size: min(420px, 46%);
  block-size: 2px;
  background: linear-gradient(90deg, var(--cyan) 0%, var(--lime) 48%, transparent 100%);
  opacity: .8;
}

.footer-top {
  width: var(--shell);
  margin-inline: auto;
  display: grid;
  grid-template-columns: minmax(250px, 1.05fr) minmax(0, 1.5fr);
  gap: clamp(1.6rem, 4vw, 3.4rem);
  align-items: start;
}

.footer-brand { min-width: 0; }
.footer-brand-line {
  font-family: var(--font-display);
  font-size: 1.06rem;
  font-weight: 800;
  letter-spacing: .01em;
  line-height: 1.4;
  color: var(--sand);
}
.footer-brand-line::before {
  content: "";
  display: block;
  inline-size: 3.4rem;
  block-size: 3px;
  margin-block-end: .9rem;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--lime), transparent);
}
.footer-blurb {
  margin-block-start: .7rem;
  max-width: 34ch;
  font-size: .92rem;
  line-height: 1.75;
  color: var(--text-dim);
}
.footer-btn { margin-block-start: 1.15rem; }

.footer-nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem 1.8rem;
}
.footer-col { min-width: 0; }
.footer-col-title {
  font-family: var(--font-mono);
  font-size: .68rem;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--rock);
  margin-block-end: .8rem;
}
.footer-list {
  display: flex;
  flex-direction: column;
  gap: .45rem;
  font-size: .92rem;
}
.footer-list a {
  display: inline-block;
  color: var(--text-soft);
  transition: color .18s var(--ease), transform .18s var(--ease);
}
.footer-list a:hover {
  color: var(--cyan);
  transform: translateX(3px);
}

.footer-facts {
  display: flex;
  flex-direction: column;
  gap: .55rem;
  font-family: var(--font-mono);
  font-size: .78rem;
  line-height: 1.65;
  color: var(--text-soft);
  word-break: break-word;
}
.footer-fact-key {
  display: inline-block;
  min-inline-size: 2.4rem;
  margin-inline-end: .45rem;
  color: var(--rock);
  font-size: .7rem;
  letter-spacing: .1em;
}

.footer-bottom {
  width: var(--shell);
  margin: clamp(1.6rem, 4vw, 2.4rem) auto 0;
  padding-block-start: 1.05rem;
  border-block-start: 1px dashed rgba(109,123,134,.32);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: .5rem 1.4rem;
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .06em;
  color: var(--rock);
}
.footer-copy, .footer-icp { margin: 0; }
.footer-icp { color: var(--text-dim); }

/* =========================================================
   响应式：平板 / 移动
   ========================================================= */
@media (max-width: 1080px) {
  .brand-note { display: none; }
  .nav-link { padding: .44rem .62rem; font-size: .86rem; }
  .header-cta { padding-inline: .95rem; font-size: .88rem; }
}

@media (max-width: 960px) {
  :root { --shell: min(var(--shell-max), calc(100% - 1.6rem)); }

  .site-header { padding-block-start: .6rem; }
  .header-shell { padding: .42rem .42rem .42rem .8rem; gap: .6rem; }
  .header-cta { display: none; }
  .nav-toggle { display: inline-flex; }

  .nav-cluster { display: none; }
  .nav-cluster[data-open="true"] {
    display: block;
    position: fixed;
    inset-inline: .7rem;
    inset-block-end: .7rem;
    z-index: 95;
    padding: .85rem;
    border: 1px solid var(--line-cyan);
    border-radius: var(--r-lg);
    background:
      radial-gradient(520px 200px at 100% 0%, rgba(39,230,245,.16), transparent 72%),
      linear-gradient(165deg, #0D2740 0%, #040E18 74%);
    box-shadow: 0 -26px 64px -26px rgba(0,0,0,.95), inset 0 1px 0 rgba(138,247,255,.12);
    animation: nav-rise .24s var(--ease) both;
  }
  .nav-cluster[data-open="true"] .nav-list {
    display: grid;
    grid-template-columns: 1fr;
    gap: .3rem;
  }
  .nav-cluster[data-open="true"] .nav-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: .72rem .9rem;
    border-radius: var(--r-sm);
    background: rgba(243,239,228,.05);
    font-size: .98rem;
    color: var(--sand);
  }
  .nav-cluster[data-open="true"] .nav-link::after {
    content: "→";
    font-family: var(--font-mono);
    color: rgba(109,123,134,.9);
  }
  .nav-cluster[data-open="true"] .nav-link:hover { background: rgba(39,230,245,.12); }
  .nav-cluster[data-open="true"] .nav-link[aria-current="page"] {
    background: linear-gradient(135deg, var(--cyan) 0%, var(--cyan-glow) 100%);
    color: var(--ink-950);
  }
  .nav-cluster[data-open="true"] .nav-link[aria-current="page"]::after { color: var(--ink-950); }
  .nav-cluster[data-open="true"] .nav-cta {
    display: inline-flex;
    inline-size: 100%;
    margin-block-start: .7rem;
  }

  .footer-top { grid-template-columns: 1fr; }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-col--facts { grid-column: 1 / -1; }
}

@keyframes nav-rise {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 860px) {
  .grid--2, .grid--3, .grid--split { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  :root { --shell: calc(100% - 1.3rem); }

  h1 { letter-spacing: -.02em; }
  .brand-mark { inline-size: 1.95rem; block-size: 1.95rem; }
  .brand-name { font-size: .95rem; }
  .nav-toggle { padding: .46rem .78rem .46rem .64rem; font-size: .82rem; }
  .scroll-meter { margin-block-start: .35rem; }

  .footer-nav { grid-template-columns: 1fr; gap: 1.2rem; }
  .footer-col--facts { grid-column: auto; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 380px) {
  .nav-toggle-text { display: none; }
}

/* =========================================================
   动效偏好与打印
   ========================================================= */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .header-shell::after { opacity: .35; animation: none; }
  .frame:hover::after { transform: rotate(12deg); }
  .btn:hover, .footer-list a:hover { transform: none; }
}

@media print {
  .site-header, .site-footer, .skip-link, .scroll-meter { display: none !important; }
  body { background: #fff; color: #111; }
}