/* =========================================================
   鼎利娱乐汇 · site.css
   共享外壳 / 基础组件 / 响应式 / 无障碍
   ========================================================= */

:root {
  /* 色板 */
  --ink-900: #050B14;
  --ink-850: #081524;
  --ink-700: #0E1E30;
  --ink-500: #1B3550;
  --white: #EAF4FF;
  --muted: #93A9BF;
  --cyan: #4FE3D0;
  --amber: #F2B457;
  --coral: #FF6B4A;
  --paper: #F4E9D8;
  --brown: #2A1D16;
  --brick: #A8442F;

  /* 线条 */
  --line: rgba(147, 169, 191, 0.18);
  --line-soft: rgba(147, 169, 191, 0.10);
  --line-strong: rgba(79, 227, 208, 0.38);

  /* 字体 */
  --font-display: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-editorial: "Noto Serif SC", "Songti SC", "STSong", "SimSun", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  /* 字号阶梯 64/44/32/24/19/17/15/13 */
  --step-6: 4rem;
  --step-5: 2.75rem;
  --step-4: 2rem;
  --step-3: 1.5rem;
  --step-2: 1.1875rem;
  --step-1: 1.0625rem;
  --step-0: 1rem;
  --step--1: 0.9375rem;
  --step--2: 0.8125rem;

  /* 间距 8 基准 */
  --sp-1: 8px;
  --sp-2: 16px;
  --sp-3: 24px;
  --sp-4: 40px;
  --sp-5: 72px;
  --sp-6: 112px;

  --header-mobile-h: 72px;
  --notch: 20px;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--ink-900);
  color: var(--white);
  font-family: var(--font-body);
  font-size: var(--step-0);
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg, video, picture { max-width: 100%; }
img { height: auto; display: block; }
button { font: inherit; color: inherit; }
a { color: var(--cyan); text-decoration: none; }
strong, b { font-weight: 700; }

::selection { background: var(--cyan); color: #04140F; }

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

[id] { scroll-margin-top: 148px; }

body.nav-locked { overflow: hidden; }

/* 固定头部下的主体起始留白 */
main {
  display: block;
  padding-top: clamp(104px, 14vh, 140px);
}

/* ---------- 通用容器 / 节奏 ---------- */
.container {
  width: min(1280px, 100% - 48px);
  margin-inline: auto;
}

.section { padding-block: clamp(48px, 8vw, 112px); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 24px;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), rgba(79, 227, 208, 0.1));
}

.display-1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.5rem, 6vw, 4rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--white);
}

.display-2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--white);
}

.serif-title {
  font-family: var(--font-editorial);
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1.35;
}

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

.spot-rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: linear-gradient(90deg, rgba(79, 227, 208, 0.55), rgba(242, 180, 87, 0.28) 45%, rgba(79, 227, 208, 0));
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  font-family: var(--font-body);
  font-size: var(--step--2);
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.18s ease;
}

.btn:focus-visible {
  outline: none;
  box-shadow: inset 0 0 0 2px var(--amber);
}

.btn-solid {
  background: var(--cyan);
  color: #04140F;
}

.btn-solid:hover {
  background: #7DF0E2;
  transform: translateY(-1px);
}

.btn-ghost {
  color: var(--white);
  background: rgba(79, 227, 208, 0.07);
  border-color: var(--line-strong);
}

.btn-ghost:hover {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(79, 227, 208, 0.13);
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 50%;
  z-index: 200;
  padding: 10px 22px;
  background: var(--cyan);
  color: #04140F;
  font-size: var(--step--1);
  font-weight: 700;
  text-decoration: none;
  transform: translate(-50%, -180%);
  transition: transform 0.22s var(--ease);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translate(-50%, 0);
  outline: none;
}

/* =========================================================
   头部
   ========================================================= */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 120;
  background: transparent;
  transition: background 0.35s ease, box-shadow 0.35s ease;
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, rgba(79, 227, 208, 0), rgba(79, 227, 208, 0.34) 22%, rgba(242, 180, 87, 0.26) 62%, rgba(79, 227, 208, 0));
  opacity: 0.55;
  pointer-events: none;
}

.site-header[data-scrolled="true"] {
  background: rgba(5, 11, 20, 0.95);
  box-shadow: 0 20px 44px -28px rgba(0, 0, 0, 0.95);
}

.scroll-progress {
  --progress: 0%;
  position: absolute;
  left: 0;
  bottom: 0;
  height: 2px;
  width: var(--progress);
  background: linear-gradient(90deg, var(--cyan), var(--amber));
  box-shadow: 0 0 12px rgba(79, 227, 208, 0.55);
  pointer-events: none;
  transition: width 0.12s linear;
}

.header-inner {
  width: min(1280px, 100% - 48px);
  margin-inline: auto;
  padding-block: 16px 0;
  transition: padding 0.3s ease;
}

.header-top {
  position: relative;
  z-index: 3;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.site-header[data-scrolled="true"] .header-inner { padding-block: 10px 0; }

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--white);
  text-decoration: none;
  min-width: 0;
}

.brand-mark {
  position: relative;
  flex: none;
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  background: linear-gradient(145deg, var(--cyan) 0%, #1E8E86 58%, var(--amber) 100%);
  clip-path: polygon(0 0, 100% 0, 100% 64%, 64% 100%, 0 100%);
  box-shadow: 0 0 22px -6px rgba(79, 227, 208, 0.7);
}

.brand-mark i {
  width: 10px;
  height: 10px;
  background: var(--ink-900);
  transform: rotate(45deg);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.brand-name {
  font-family: var(--font-display);
  font-size: var(--step-2);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  color: var(--white);
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
  overflow: hidden;
  transition: opacity 0.24s ease, transform 0.24s ease, max-height 0.3s ease;
  max-height: 16px;
}

.site-header[data-scrolled="true"] .brand-sub {
  opacity: 0;
  transform: translateY(-4px);
  max-height: 0;
}

/* 工具区 */
.header-tools {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: none;
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  padding: 11px 12px;
  background: rgba(79, 227, 208, 0.08);
  border: 1px solid var(--line-strong);
  color: var(--white);
  cursor: pointer;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
  transition: background 0.2s ease, border-color 0.2s ease;
}

.nav-toggle:hover { background: rgba(79, 227, 208, 0.16); }

.nav-toggle-box {
  position: relative;
  display: block;
  width: 18px;
  height: 12px;
}

.nav-toggle-box i {
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--cyan);
  transition: transform 0.26s var(--ease), opacity 0.18s ease;
}

.nav-toggle-box i:nth-child(1) { top: 0; }
.nav-toggle-box i:nth-child(2) { top: 5px; }
.nav-toggle-box i:nth-child(3) { top: 10px; }

.nav-toggle[aria-expanded="true"] .nav-toggle-box i:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-box i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-box i:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* 分类索引条 */
.nav {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: stretch;
  gap: 24px;
  margin-top: 14px;
  border-top: 1px solid var(--line);
}

.nav-list {
  display: flex;
  flex: 1 1 auto;
  min-width: 0;
}

.nav-item {
  flex: 1 1 0;
  min-width: 0;
  border-left: 1px solid var(--line-soft);
}

.nav-item:first-child { border-left: 0; }

.nav-link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 12px 14px 15px;
  font-size: var(--step--1);
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.2s ease, background 0.2s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 9px;
  height: 1px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.26s var(--ease);
}

.nav-link:hover {
  color: var(--white);
  background: rgba(79, 227, 208, 0.05);
}

.nav-link:hover::after { transform: scaleX(1); }

.nav-num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  color: rgba(147, 169, 191, 0.62);
  transition: color 0.2s ease;
}

.nav-link:hover .nav-num { color: var(--amber); }

.nav-link[aria-current="page"] {
  color: var(--cyan);
  background: linear-gradient(180deg, rgba(79, 227, 208, 0.1), rgba(79, 227, 208, 0));
}

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

.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  box-shadow: 0 0 10px rgba(79, 227, 208, 0.75);
}

.nav-note { display: none; }

/* =========================================================
   页脚
   ========================================================= */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 112px);
  color: var(--muted);
  background:
    radial-gradient(120% 90% at 10% 0%, rgba(79, 227, 208, 0.11), transparent 58%),
    radial-gradient(90% 80% at 92% 6%, rgba(242, 180, 87, 0.09), transparent 62%),
    var(--ink-900);
  border-top: 1px solid var(--line);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--cyan) 16%, var(--amber) 52%, var(--coral) 84%, transparent);
  opacity: 0.6;
}

.footer-inner {
  width: min(1280px, 100% - 48px);
  margin-inline: auto;
  padding-block: clamp(48px, 7vw, 72px) 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.25fr 1.35fr 0.95fr 1.15fr;
  gap: 48px 40px;
  padding-bottom: clamp(36px, 5vw, 56px);
}

.footer-col { min-width: 0; }

.footer-title {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--white);
  padding-bottom: 10px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.brand--footer .brand-name { font-size: var(--step-2); }

.footer-tagline {
  margin: 16px 0 22px;
  max-width: 30ch;
  font-size: var(--step--1);
  line-height: 1.8;
  color: var(--muted);
}

.footer-links {
  display: grid;
  gap: 10px;
}

.footer-links--tight { gap: 8px; }

.footer-links a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: var(--step--1);
  color: var(--muted);
  text-decoration: none;
  transition: color 0.2s ease, transform 0.2s ease;
}

.footer-links a:hover {
  color: var(--cyan);
  transform: translateX(3px);
}

.footer-links em {
  margin-left: auto;
  font-style: normal;
  font-size: 11px;
  letter-spacing: 0.04em;
  color: rgba(147, 169, 191, 0.55);
  white-space: nowrap;
}

.footer-num {
  flex: none;
  font-family: var(--font-mono);
  font-size: 11px;
  color: rgba(147, 169, 191, 0.6);
  min-width: 18px;
}

.footer-links a:hover .footer-num { color: var(--amber); }

.footer-more {
  display: inline-block;
  margin-top: 16px;
  padding-bottom: 2px;
  font-size: var(--step--2);
  color: var(--amber);
  text-decoration: none;
  border-bottom: 1px solid rgba(242, 180, 87, 0.35);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.footer-more:hover {
  color: #FFCF86;
  border-bottom-color: #FFCF86;
}

.contact-list {
  display: grid;
  gap: 14px;
  font-size: var(--step--1);
}

.contact-list li {
  display: flex;
  flex-direction: column;
  gap: 4px;
  line-height: 1.6;
}

.contact-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(147, 169, 191, 0.6);
}

.contact-list a {
  color: var(--white);
  text-decoration: none;
  font-size: var(--step--2);
  word-break: break-all;
  border-bottom: 1px solid var(--line);
  transition: color 0.2s ease, border-color 0.2s ease;
}

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

.contact-note {
  margin-top: 16px;
  font-size: 12px;
  line-height: 1.7;
  color: rgba(147, 169, 191, 0.75);
}

/* 返回顶部 */
.to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 130;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  font-size: var(--step--2);
  font-weight: 700;
  color: #04140F;
  background: var(--cyan);
  border: 0;
  cursor: pointer;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  box-shadow: 0 14px 34px -16px rgba(79, 227, 208, 0.85);
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity 0.25s ease, transform 0.25s var(--ease), visibility 0.25s ease, background 0.2s ease;
}

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

.to-top:hover { background: #7DF0E2; }

.to-top:focus-visible {
  outline: none;
  box-shadow: inset 0 0 0 2px var(--ink-900), 0 14px 34px -16px rgba(79, 227, 208, 0.85);
}

/* 页脚底条 */
.footer-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-block: 20px 32px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: rgba(147, 169, 191, 0.72);
}

.footer-copy { margin: 0; }

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

.footer-legal a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-legal a:hover { color: var(--cyan); }

/* =========================================================
   通用内容组件
   ========================================================= */
.crumbs {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: rgba(147, 169, 191, 0.78);
}

.crumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

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

.crumbs li + li::before {
  content: "/";
  color: rgba(147, 169, 191, 0.4);
}

.crumbs a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

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

.prose { max-width: 68ch; }

.prose > * + * { margin-top: 1.15em; }

.prose h2,
.prose h3 {
  font-family: var(--font-editorial);
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1.4;
  margin-top: 1.6em;
}

.prose h2 { font-size: var(--step-3); }
.prose h3 { font-size: var(--step-2); }

.prose ul,
.prose ol {
  padding-left: 1.35em;
  list-style: disc;
}

.prose ol { list-style: decimal; }

.prose li + li { margin-top: 0.4em; }

.prose blockquote {
  padding-left: 20px;
  border-left: 3px solid var(--brick);
  font-family: var(--font-editorial);
  font-size: var(--step-2);
  color: var(--brown);
}

.grid {
  display: grid;
  gap: clamp(16px, 2.5vw, 32px);
}

.grid-12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.cut-panel {
  padding: clamp(20px, 3vw, 32px);
  background: var(--ink-700);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
}

.paper-panel {
  padding: clamp(24px, 4vw, 56px);
  background: var(--paper);
  color: var(--brown);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

.paper-panel :is(h1, h2, h3, h4) { color: var(--brown); }

.paper-panel a {
  color: var(--brick);
  text-decoration: underline;
  text-decoration-color: rgba(168, 68, 47, 0.42);
  text-underline-offset: 3px;
}

.paper-panel .serif-title { color: var(--brick); }

/* 图像容器基础 */
.media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: linear-gradient(135deg, var(--ink-700) 0%, var(--ink-500) 100%);
  border: 1px solid var(--line);
}

.media > img,
.media > picture,
.media > svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(135deg, rgba(79, 227, 208, 0) 42%, rgba(79, 227, 208, 0.16) 72%, rgba(242, 180, 87, 0.14) 100%);
}

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

.media--cut {
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 0 100%);
}

.media-caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: rgba(147, 169, 191, 0.82);
}

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  line-height: 1.6;
  color: var(--cyan);
  background: rgba(79, 227, 208, 0.08);
  border: 1px solid var(--line-strong);
}

.tag--amber {
  color: var(--amber);
  background: rgba(242, 180, 87, 0.1);
  border-color: rgba(242, 180, 87, 0.4);
}

.tag--coral {
  color: var(--coral);
  background: rgba(255, 107, 74, 0.1);
  border-color: rgba(255, 107, 74, 0.42);
}

/* ---------- 显现动画（JS 可用时才隐藏） ---------- */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.32s ease, transform 0.32s var(--ease);
  transition-delay: var(--reveal-delay, 0ms);
}

.has-js [data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: none;
}

/* =========================================================
   响应式
   ========================================================= */
@media (max-width: 1180px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 40px 32px; }
}

@media (max-width: 1100px) and (min-width: 961px) {
  .brand-sub { display: none; }
  .nav-link { padding-inline: 10px; font-size: var(--step--2); gap: 6px; }
  .nav-link::after { left: 10px; right: 10px; }
}

@media (max-width: 960px) {
  [id] { scroll-margin-top: 96px; }

  main { padding-top: clamp(88px, 12vh, 104px); }

  .header-inner {
    width: min(100% - 32px, 720px);
    padding-block: 10px 10px;
  }

  .site-header[data-scrolled="true"] .header-inner { padding-block: 8px; }

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

  .nav {
    position: fixed;
    inset: 0 0 0 0;
    z-index: 2;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    margin: 0;
    padding: calc(var(--header-mobile-h) + 16px) 24px 48px;
    border-top: 0;
    overflow-y: auto;
    background:
      radial-gradient(120% 70% at 18% 0%, rgba(79, 227, 208, 0.16), transparent 58%),
      radial-gradient(90% 60% at 92% 8%, rgba(242, 180, 87, 0.1), transparent 62%),
      linear-gradient(180deg, #050B14 0%, #081524 62%, #0E1E30 100%);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-14px);
    transition: opacity 0.28s ease, transform 0.36s var(--ease), visibility 0.36s ease;
  }

  .site-header[data-open="true"] .nav {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .site-header[data-open="true"] { background: rgba(5, 11, 20, 0.95); }

  .nav-list {
    flex: none;
    flex-direction: column;
    border-top: 1px solid var(--line);
  }

  .nav-item {
    flex: none;
    border-left: 0;
    border-bottom: 1px solid var(--line);
  }

  .nav-link {
    padding: 18px 4px;
    font-size: var(--step-3);
    font-weight: 700;
    letter-spacing: -0.01em;
    gap: 14px;
    background: none;
  }

  .nav-link::after {
    left: 0;
    right: auto;
    bottom: 12px;
    width: 26px;
  }

  .nav-link:hover { background: none; }

  .nav-num { font-size: 11px; }

  .nav-note {
    display: block;
    margin-top: 22px;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.14em;
    color: rgba(147, 169, 191, 0.7);
  }

  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  .prose { max-width: none; }
}

@media (max-width: 640px) {
  .container,
  .footer-inner,
  .header-inner { width: min(100% - 32px, 640px); }

  .brand-sub { display: none; }
  .brand-name { font-size: var(--step-1); }

  .header-tools .btn-ghost { display: none; }

  .btn { padding: 10px 15px; font-size: var(--step--2); }

  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-links em { display: none; }

  .footer-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .footer-legal { gap: 14px; }

  .to-top { right: 16px; bottom: 16px; padding: 9px 14px; }

  .grid-3,
  .grid-12 { grid-template-columns: 1fr; }
}

/* =========================================================
   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;
  }

  .has-js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }

  .to-top { transform: none; }
  .site-header[data-scrolled="true"] .brand-sub { opacity: 1; transform: none; }
}