/* ============================================================
   MagicDB Studio 官网 — 精致深色设计系统
   单一强调色（电光蓝）· 近黑画布 · 克制动效 · 柔和中性阴影
   纯手写 CSS，无外部依赖，file:// 可直接打开
   ============================================================ */

:root {
  /* 画布层次：近黑 → 抬升表面 */
  --bg: #08090d;
  --bg-2: #0c0e14;
  --bg-3: #12151d;
  --surface: #0f1218;
  --surface-2: #141822;

  /* 单一强调色：电光蓝 */
  --accent: #5b8cff;
  --accent-hi: #85a9ff;
  --accent-dim: rgba(91, 140, 255, 0.12);
  --accent-line: rgba(91, 140, 255, 0.28);

  /* 文本层级 */
  --text: #f2f5fa;
  --text-2: #a4adbe;
  --text-3: #6b7488;

  /* 描边与玻璃 */
  --line: rgba(148, 163, 184, 0.1);
  --line-2: rgba(148, 163, 184, 0.16);
  --glass: rgba(20, 24, 34, 0.6);
  --glass-strong: rgba(16, 19, 27, 0.9);

  /* 柔和中性阴影（无彩色发光） */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 40px 100px rgba(0, 0, 0, 0.6);

  --radius: 12px;
  --radius-lg: 18px;

  /* 兼容别名（子页 inline style 仍引用 --cyan / --violet） */
  --cyan: #5b8cff;
  --violet: #85a9ff;

  --font-sans: "PingFang SC", "Microsoft YaHei", "Segoe UI", "Helvetica Neue",
    "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Cascadia Code", "SF Mono", Consolas,
    ui-monospace, SFMono-Regular, Menlo, monospace;
  --nav-h: 66px;
  --maxw: 1180px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 16px); }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---------- 全局氛围：极克制的单色光晕 + 细网格 ---------- */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(900px 500px at 50% -10%, rgba(91, 140, 255, 0.1), transparent 70%),
    var(--bg);
  pointer-events: none;
}

.grid-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(148, 163, 184, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(148, 163, 184, 0.035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 80% 55% at 50% 0%, #000 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 80% 55% at 50% 0%, #000 20%, transparent 75%);
  pointer-events: none;
}

::selection { background: rgba(91, 140, 255, 0.28); color: #fff; }

a { color: var(--accent); text-decoration: none; transition: color 0.2s; }
a:hover { color: var(--accent-hi); }

img { max-width: 100%; display: block; }

.container { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.mono { font-family: var(--font-mono); }

/* ---------- 顶部导航 ---------- */
.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  z-index: 100;
  background: rgba(8, 9, 13, 0.7);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s, background 0.3s;
}
.site-nav.scrolled {
  border-bottom-color: var(--line);
  background: rgba(8, 9, 13, 0.86);
}

.site-nav .container {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 650;
  font-size: 17px;
  color: var(--text);
  letter-spacing: -0.01em;
  white-space: nowrap;
}
.brand img { width: 28px; height: 28px; }
.brand .ver {
  display: inline-flex;
  align-items: center;
  min-height: 22px;
  font-family: var(--font-sans);
  font-size: 11px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.08em;
  color: #dce7ff;
  background: rgba(91, 140, 255, 0.2);
  border: 1px solid rgba(133, 169, 255, 0.5);
  border-radius: 999px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08);
  padding: 4px 9px;
  margin-left: 3px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: auto;
  list-style: none;
}

.nav-links a {
  color: var(--text-2);
  font-size: 14.5px;
  padding: 8px 14px;
  border-radius: 8px;
  transition: color 0.2s, background 0.2s;
}
.nav-links a:hover { color: var(--text); }
.nav-links a.active { color: var(--text); }

.nav-cta {
  margin-left: 10px;
  padding: 8px 18px !important;
  color: #04101f !important;
  font-weight: 600;
  background: var(--accent);
  border-radius: 9px;
  transition: background 0.2s, transform 0.2s, box-shadow 0.25s !important;
}
.nav-cta:hover {
  background: var(--accent-hi);
  color: #04101f !important;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(91, 140, 255, 0.35);
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 42px; height: 42px;
  background: transparent;
  border: 1px solid var(--line-2);
  border-radius: 10px;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}
.nav-toggle span {
  display: block;
  width: 20px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s, opacity 0.25s;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- 通用区块 ---------- */
main { padding-top: var(--nav-h); }

.section { padding: 104px 0; position: relative; }
.section.tight { padding: 72px 0; }

.section-head { text-align: center; max-width: 700px; margin: 0 auto 60px; }

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
}

.section-head h2, .page-head h1 {
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.15;
  letter-spacing: -0.02em;
  font-weight: 700;
}

.section-head p, .page-head .sub {
  margin-top: 18px;
  color: var(--text-2);
  font-size: 16.5px;
}

/* 强调词：由渐变改为纯强调色（子页仍复用 .gradient-text） */
.gradient-text { color: var(--accent); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 11px;
  font-size: 15.5px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.25s, border-color 0.2s, background 0.2s, color 0.2s;
}
.btn-primary {
  color: #04101f;
  background: var(--accent);
}
.btn-primary:hover {
  color: #04101f;
  background: var(--accent-hi);
  transform: translateY(-2px);
  box-shadow: 0 10px 34px rgba(91, 140, 255, 0.32);
}
.btn-ghost {
  color: var(--text);
  border-color: var(--line-2);
  background: rgba(148, 163, 184, 0.04);
}
.btn-ghost:hover {
  border-color: var(--accent-line);
  color: var(--accent-hi);
  background: rgba(91, 140, 255, 0.06);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 92px 0 40px;
  overflow: hidden;
}

#particles {
  position: absolute;
  inset: 0;
  z-index: 0;
  opacity: 0.6;
}

.hero .container { position: relative; z-index: 1; text-align: center; }

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-2);
  border: 1px solid var(--line-2);
  background: var(--glass);
  border-radius: 999px;
  padding: 5px 14px 5px 8px;
  margin-bottom: 30px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.hero-eyebrow .pill {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 600;
  color: #04101f;
  background: var(--accent);
  border-radius: 999px;
  padding: 2px 9px;
}

.hero h1 {
  font-size: clamp(38px, 6.4vw, 72px);
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -0.035em;
  color: #fff;
}

.hero .sub {
  margin: 26px auto 0;
  max-width: 620px;
  color: var(--text-2);
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.65;
}
.hero .sub .mono { color: var(--accent-hi); font-weight: 600; }

.hero-ctas {
  margin-top: 38px;
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-badges {
  margin-top: 26px;
  display: flex;
  gap: 8px 20px;
  justify-content: center;
  flex-wrap: wrap;
  color: var(--text-3);
  font-size: 13px;
}
.hero-badges span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}
.hero-badges span::before {
  content: "";
  width: 5px; height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.7;
}

/* ---------- Hero 产品截图（主视觉） ---------- */
.hero-showcase {
  margin: 66px auto 0;
  max-width: 1060px;
  perspective: 1800px;
}
.showcase-window {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line-2);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
.showcase-window::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04);
  pointer-events: none;
}
.win-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
}
.win-head i { width: 11px; height: 11px; border-radius: 50%; background: #2a2f3a; }
.win-head i:nth-child(1) { background: #ff5f57; }
.win-head i:nth-child(2) { background: #febc2e; }
.win-head i:nth-child(3) { background: #28c840; }
.win-head span {
  margin-left: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-3);
}
.win-shot { display: block; width: 100%; height: auto; }
.hero-glow {
  position: absolute;
  left: 50%; top: 40%;
  width: 70%; height: 60%;
  transform: translate(-50%, 0);
  background: radial-gradient(closest-side, rgba(91, 140, 255, 0.22), transparent 75%);
  filter: blur(40px);
  z-index: 0;
  pointer-events: none;
}

/* ---------- 信任条（数据源 logo 云 / 指标） ---------- */
.trust-strip {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding: 30px 0;
}
.trust-strip .container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px 40px;
  flex-wrap: wrap;
}
.trust-label {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
}
.trust-list {
  display: flex;
  align-items: center;
  gap: 12px 26px;
  flex-wrap: wrap;
}
.trust-list span {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--text-2);
  transition: color 0.2s;
}
.trust-list span:hover { color: var(--text); }

/* 指标条 */
.stats-bar {
  margin: 0 auto;
  max-width: 900px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--glass);
  overflow: hidden;
}
.stats-bar .stat + .stat { border-left: 1px solid var(--line); }
.stat {
  padding: 30px 20px;
  text-align: center;
}
.stat .num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 3.6vw, 44px);
  font-weight: 700;
  color: #fff;
  letter-spacing: -0.02em;
}
.stat .num .suffix { color: var(--accent); }
.stat .label { margin-top: 6px; color: var(--text-2); font-size: 13.5px; }

/* ---------- 玻璃卡片通用 ---------- */
.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: transform 0.3s, border-color 0.3s, box-shadow 0.3s;
}
.card:hover {
  transform: translateY(-3px);
  border-color: var(--line-2);
  box-shadow: var(--shadow-md);
}

/* ---------- 核心亮点 Bento ---------- */
.pillar-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.pillar-card { padding: 32px 30px; position: relative; }
.pillar-card .p-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px; height: 34px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  border: 1px solid var(--accent-line);
  border-radius: 9px;
  background: var(--accent-dim);
}
.pillar-card h3 { font-size: 20px; margin: 18px 0 12px; letter-spacing: -0.01em; }
.pillar-card p { color: var(--text-2); font-size: 14.5px; line-height: 1.75; }

/* ---------- 功能卡 ---------- */
.feat-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.feat-card { padding: 30px 26px; }
.feat-card .f-icon {
  width: 44px; height: 44px;
  display: grid; place-items: center;
  border-radius: 11px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-line);
  margin-bottom: 18px;
}
.feat-card .f-icon svg { width: 22px; height: 22px; stroke: var(--accent); fill: none; }
.feat-card h3 { font-size: 17px; margin-bottom: 10px; letter-spacing: -0.01em; }
.feat-card p { color: var(--text-2); font-size: 14px; line-height: 1.75; }

/* ---------- AI 专区 ---------- */
.ai-cap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin-bottom: 64px;
}
.ai-cap-grid .feat-card .stack-list { margin-top: 16px; }
.ai-wrap {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 48px;
  align-items: center;
}
.ai-copy h3 { font-size: clamp(24px, 3vw, 32px); margin-bottom: 18px; letter-spacing: -0.02em; line-height: 1.2; }
.ai-copy > p { color: var(--text-2); margin-bottom: 14px; font-size: 15.5px; }
.ai-copy ul { list-style: none; margin-top: 24px; }
.ai-copy li {
  position: relative;
  padding-left: 30px;
  color: var(--text);
  font-size: 15px;
  margin-bottom: 14px;
}
.ai-copy li::before {
  content: "";
  position: absolute;
  left: 0; top: 6px;
  width: 18px; height: 18px;
  border-radius: 6px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-line);
}
.ai-copy li::after {
  content: "";
  position: absolute;
  left: 6px; top: 10px;
  width: 5px; height: 8px;
  border: solid var(--accent);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

.chat-demo {
  background: var(--surface);
  border: 1px solid var(--line-2);
  border-radius: var(--radius-lg);
  padding: 22px;
  box-shadow: var(--shadow-md);
}
.chat-bubble {
  max-width: 90%;
  border-radius: 14px;
  padding: 12px 16px;
  font-size: 14.5px;
  margin-bottom: 14px;
  line-height: 1.6;
}
.chat-bubble.user {
  margin-left: auto;
  color: #eef3ff;
  background: rgba(91, 140, 255, 0.14);
  border: 1px solid var(--accent-line);
  border-bottom-right-radius: 4px;
}
.chat-bubble.ai {
  color: var(--text-2);
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-bottom-left-radius: 4px;
}
.chat-bubble.ai .who {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  margin-bottom: 8px;
  letter-spacing: 0.04em;
}

.code-block {
  background: #060810;
  border: 1px solid var(--line-2);
  border-radius: 12px;
  overflow: hidden;
  margin-top: 8px;
}
.code-block .code-head {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
}
.code-block .code-head i { width: 9px; height: 9px; border-radius: 50%; background: #2a2f3a; }
.code-block .code-head i:nth-child(1) { background: #ff5f57; }
.code-block .code-head i:nth-child(2) { background: #febc2e; }
.code-block .code-head i:nth-child(3) { background: #28c840; }
.code-block .code-head span {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-3);
}
.code-block pre {
  padding: 16px 18px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: #c8d3e8;
}
.code-block .kw { color: var(--accent-hi); font-weight: 600; }
.code-block .fn { color: #c792ea; }
.code-block .str { color: #7ee787; }
.code-block .num-l { color: #f2cc60; }
.code-block .cm { color: #4b5568; font-style: italic; }

/* ---------- 截图展示 ---------- */
.shot-tabs {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 34px;
}
.shot-tab {
  font-size: 14px;
  color: var(--text-2);
  background: transparent;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  padding: 8px 18px;
  cursor: pointer;
  transition: all 0.2s;
  font-family: var(--font-sans);
}
.shot-tab:hover { color: var(--text); border-color: var(--accent-line); }
.shot-tab.active {
  color: #04101f;
  font-weight: 600;
  background: var(--accent);
  border-color: transparent;
}
.shot-panel { display: none; }
.shot-panel.active { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; animation: fadeUp 0.45s ease both; }
.shot-panel.single { grid-template-columns: 1fr; max-width: 900px; margin: 0 auto; }

.shot-item {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line-2);
  background: var(--bg-2);
  box-shadow: var(--shadow-sm);
  transition: border-color 0.3s, box-shadow 0.3s, transform 0.3s;
}
.shot-item:hover {
  border-color: var(--accent-line);
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}
.shot-item img { width: 100%; height: auto; aspect-ratio: 16 / 10; object-fit: cover; object-position: top center; }
.shot-item figcaption {
  padding: 11px 16px;
  font-size: 13px;
  color: var(--text-2);
  background: var(--bg-2);
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
}

/* ---------- 数据库矩阵 ---------- */
.db-groups { display: flex; flex-direction: column; gap: 32px; }
.db-group-title {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 18px;
  color: var(--text);
}
.db-group-title .count {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--accent);
  border: 1px solid var(--accent-line);
  background: var(--accent-dim);
  border-radius: 999px;
  padding: 2px 10px;
}
.badge-wall { display: flex; flex-wrap: wrap; gap: 10px; }
.db-badge {
  position: relative;
  font-family: var(--font-mono);
  font-size: 13.5px;
  color: var(--text-2);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 15px;
  transition: border-color 0.25s, color 0.25s, transform 0.25s;
  cursor: default;
}
.db-badge:hover {
  border-color: var(--accent-line);
  color: var(--text);
  transform: translateY(-2px);
}
.db-badge.core { color: var(--text); border-color: var(--line-2); }
.db-badge.core::before {
  content: "";
  display: inline-block;
  width: 6px; height: 6px;
  border-radius: 50%;
  margin-right: 8px;
  background: var(--accent);
}
.tag-exp {
  position: absolute;
  top: -8px; right: -6px;
  font-size: 9.5px;
  font-family: var(--font-sans);
  color: #f2cc60;
  background: rgba(90, 66, 0, 0.7);
  border: 1px solid rgba(242, 204, 96, 0.4);
  border-radius: 999px;
  padding: 0 7px;
  line-height: 16px;
}
.db-legend {
  margin-top: 24px;
  color: var(--text-3);
  font-size: 13px;
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.db-legend i {
  display: inline-block;
  width: 7px; height: 7px;
  border-radius: 50%;
  margin-right: 6px;
  background: var(--accent);
}
.db-legend .exp i { background: #f2cc60; }

/* ---------- 数据源分类 Tab ---------- */
.db-tab {
  font-size: 14px;
  color: var(--text-2);
  background: transparent;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  padding: 8px 18px;
  cursor: pointer;
  transition: all 0.2s;
  font-family: var(--font-sans);
}
.db-tab:hover { color: var(--text); border-color: var(--accent-line); }
.db-tab.active {
  color: #04101f;
  font-weight: 600;
  background: var(--accent);
  border-color: transparent;
}
.db-panel { display: none; }
.db-panel.active { display: block; animation: fadeUp 0.45s ease both; }

/* ---------- 下载区 ---------- */
.dl-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}
.dl-card { padding: 30px 24px; display: flex; flex-direction: column; align-items: flex-start; }
.dl-card .os-icon {
  width: 50px; height: 50px;
  display: grid; place-items: center;
  border-radius: 13px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-line);
  margin-bottom: 18px;
}
.dl-card .os-icon svg { width: 26px; height: 26px; stroke: var(--accent); fill: none; }
.dl-card h3 { font-size: 18px; letter-spacing: -0.01em; }
.dl-card .pkg {
  margin-top: 6px;
  color: var(--text-2);
  font-size: 13.5px;
}
.dl-card .filename {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--text-3);
  word-break: break-all;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px 10px;
  width: 100%;
}
.dl-card .btn { margin-top: 16px; width: 100%; justify-content: center; padding: 11px 16px; font-size: 15px; }
.download-menu { position: relative; width: 100%; margin-top: auto; }
.download-menu summary { list-style: none; cursor: pointer; }
.download-menu summary::-webkit-details-marker { display: none; }
.download-menu summary::after { content: "?"; margin-left: 8px; font-size: 18px; line-height: 1; transition: transform 0.2s ease; }
.download-menu[open] summary::after { transform: rotate(180deg); }
.download-options {
  position: absolute;
  z-index: 10;
  right: 0;
  bottom: calc(100% + 8px);
  width: min(320px, calc(100vw - 48px));
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.28);
}
.download-options a { display: grid; grid-template-columns: auto 1fr; gap: 3px 10px; padding: 10px; border-radius: 8px; color: var(--text-1); }
.download-options a:hover { background: var(--accent-dim); }
.download-options strong { color: var(--accent); }
.download-options span { color: var(--text-2); font-size: 12.5px; text-align: right; }
.download-options code { grid-column: 1 / -1; color: var(--text-3); font-family: var(--font-mono); font-size: 11px; word-break: break-all; }

.dl-note {
  margin-top: 28px;
  text-align: center;
  color: var(--text-3);
  font-size: 13.5px;
}
.dl-note code { font-family: var(--font-mono); color: var(--accent); font-size: 12.5px; }

/* ---------- 尾部 CTA ---------- */
.cta-final {
  text-align: center;
  padding: 100px 0;
  position: relative;
}
.cta-final .glow {
  position: absolute;
  inset: 0;
  background: radial-gradient(600px 300px at 50% 50%, rgba(91, 140, 255, 0.12), transparent 70%);
  pointer-events: none;
}
.cta-final .container { position: relative; }
.cta-final h2 { font-size: clamp(28px, 4vw, 42px); margin-bottom: 16px; letter-spacing: -0.02em; font-weight: 700; }
.cta-final p { color: var(--text-2); margin-bottom: 34px; font-size: 16.5px; }

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--bg-2);
  padding: 56px 0 30px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.8fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 40px;
}
.footer-grid h4 {
  font-size: 13px;
  color: var(--text);
  margin-bottom: 16px;
  letter-spacing: 0.02em;
}
.footer-grid ul { list-style: none; }
.footer-grid li { margin-bottom: 9px; }
.footer-grid a { color: var(--text-2); font-size: 14px; }
.footer-grid a:hover { color: var(--accent); }
.footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 650; margin-bottom: 14px; }
.footer-brand img { width: 26px; height: 26px; }
.footer-grid p { color: var(--text-3); font-size: 13.5px; max-width: 320px; line-height: 1.7; }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  color: var(--text-3);
  font-size: 13px;
}
.footer-bottom .mono { font-size: 12px; }

/* ---------- 子页页头 ---------- */
.page-head {
  padding: 96px 0 44px;
  text-align: center;
  max-width: 760px;
  margin: 0 auto;
}

/* ---------- 更新日志时间线 ---------- */
.timeline { position: relative; max-width: 860px; margin: 0 auto; padding-left: 34px; }
.timeline::before {
  content: "";
  position: absolute;
  left: 9px; top: 8px; bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--accent), transparent);
  opacity: 0.5;
}
.tl-item { position: relative; margin-bottom: 52px; }
.tl-item::before {
  content: "";
  position: absolute;
  left: -31px; top: 8px;
  width: 13px; height: 13px;
  border-radius: 50%;
  background: var(--bg);
  border: 3px solid var(--accent);
}
.tl-item:nth-child(2)::before { border-color: var(--text-3); }
.tl-head { display: flex; align-items: baseline; gap: 14px; flex-wrap: wrap; margin-bottom: 10px; }
.tl-head h2 { font-size: 24px; letter-spacing: -0.01em; }
.tl-head .date { font-family: var(--font-mono); font-size: 13px; color: var(--text-3); }
.tl-head .current {
  font-size: 11.5px;
  color: #04101f;
  font-weight: 700;
  background: var(--accent);
  border-radius: 999px;
  padding: 2px 12px;
}
.tl-summary { color: var(--text-2); margin-bottom: 22px; max-width: 640px; }
.tl-group { margin-bottom: 18px; }
.tl-group h3 {
  font-size: 13.5px;
  font-family: var(--font-mono);
  color: var(--accent);
  letter-spacing: 0.06em;
  margin-bottom: 12px;
}
.tl-group ul { list-style: none; }
.tl-group li {
  position: relative;
  padding: 5px 0 5px 86px;
  color: var(--text-2);
  font-size: 14.5px;
}
.cl-tag {
  position: absolute;
  left: 0; top: 7px;
  font-size: 11px;
  font-weight: 600;
  border-radius: 6px;
  padding: 1px 9px;
  width: 66px;
  text-align: center;
}
.cl-tag.new { color: #7ee787; background: rgba(126, 231, 135, 0.1); border: 1px solid rgba(126, 231, 135, 0.3); }
.cl-tag.imp { color: var(--accent-hi); background: var(--accent-dim); border: 1px solid var(--accent-line); }
.cl-tag.fix { color: #f2cc60; background: rgba(242, 204, 96, 0.1); border: 1px solid rgba(242, 204, 96, 0.3); }

/* ---------- 文档页布局 ---------- */
.docs-layout {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: 44px;
  align-items: start;
  padding: 80px 0 96px;
}
.docs-toc {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 14px;
}
.docs-toc .toc-title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.14em;
  color: var(--text-3);
  padding: 0 10px 12px;
  text-transform: uppercase;
}
.docs-toc a {
  display: block;
  color: var(--text-2);
  font-size: 14px;
  padding: 8px 12px;
  border-radius: 8px;
  border-left: 2px solid transparent;
  transition: all 0.2s;
}
.docs-toc a:hover { color: var(--text); background: rgba(148, 163, 184, 0.05); }
.docs-toc a.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-dim);
}
.doc-section { margin-bottom: 64px; scroll-margin-top: calc(var(--nav-h) + 20px); }
.doc-section h2 {
  font-size: 24px;
  margin-bottom: 18px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
  letter-spacing: -0.01em;
}
.doc-section h3 { font-size: 17px; margin: 24px 0 10px; color: #cdd8ea; }
.doc-section p { color: var(--text-2); font-size: 15px; margin-bottom: 12px; }
.doc-section ul, .doc-section ol { padding-left: 22px; color: var(--text-2); font-size: 15px; margin-bottom: 12px; }
.doc-section li { margin-bottom: 6px; }
.doc-section code {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--accent-line);
  border-radius: 6px;
  padding: 1px 7px;
}
.doc-section .code-block { margin: 14px 0; }
.doc-section table {
  width: 100%;
  border-collapse: collapse;
  margin: 14px 0;
  font-size: 14px;
}
.doc-section th, .doc-section td {
  border: 1px solid var(--line);
  padding: 9px 14px;
  text-align: left;
  color: var(--text-2);
}
.doc-section th { color: var(--text); background: var(--bg-2); font-weight: 600; }
.callout {
  border: 1px solid var(--accent-line);
  border-left-width: 3px;
  background: var(--accent-dim);
  border-radius: 10px;
  padding: 14px 18px;
  margin: 14px 0;
  color: var(--text-2);
  font-size: 14.5px;
}
.callout.warn {
  border-color: rgba(242, 204, 96, 0.4);
  border-left-width: 3px;
  background: rgba(242, 204, 96, 0.06);
}
.callout strong { color: var(--text); }
.kbd {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text);
  background: rgba(148, 163, 184, 0.1);
  border: 1px solid var(--line-2);
  border-bottom-width: 2px;
  border-radius: 6px;
  padding: 1px 7px;
}
details.faq {
  border: 1px solid var(--line);
  border-radius: 10px;
  margin-bottom: 10px;
  background: var(--surface);
  overflow: hidden;
}
details.faq summary {
  cursor: pointer;
  padding: 13px 18px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  list-style: none;
}
details.faq summary::before { content: "+ "; color: var(--accent); font-family: var(--font-mono); }
details.faq[open] summary::before { content: "− "; }
details.faq .faq-body { padding: 0 18px 14px; color: var(--text-2); font-size: 14.5px; }

/* ---------- 关于页 ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.about-card { padding: 30px 28px; }
.about-card h3 { font-size: 18px; margin-bottom: 14px; display: flex; align-items: center; gap: 10px; letter-spacing: -0.01em; }
.about-card h3 .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--accent);
}
.about-card p { color: var(--text-2); font-size: 14.5px; margin-bottom: 10px; }
.about-card { position: relative; overflow: hidden; }
.card-kicker { display: block; margin-bottom: 12px; font-family: var(--font-mono); font-size: 10.5px; font-weight: 700; letter-spacing: 0.18em; color: var(--cyan); }
.about-card .vision-lead { color: var(--text-1); font-size: 15.5px; line-height: 1.8; }
.vision-card { background: radial-gradient(circle at 100% 0, rgba(87, 169, 255, 0.13), transparent 44%), var(--surface); }
.vision-card::after { content: ''; position: absolute; width: 180px; height: 180px; right: -95px; bottom: -110px; border: 1px solid var(--accent-line); border-radius: 50%; box-shadow: 0 0 70px rgba(87, 169, 255, 0.08); pointer-events: none; }
.vision-points { display: grid; gap: 15px; margin-top: 22px; }
.vision-point { display: grid; grid-template-columns: 34px 1fr; gap: 12px; align-items: start; }
.vision-index { padding-top: 2px; font-family: var(--font-mono); font-size: 11px; color: var(--cyan); opacity: 0.82; }
.vision-point strong { display: block; color: #fff; font-size: 14px; margin-bottom: 4px; }
.vision-point p { margin: 0; font-size: 13px; line-height: 1.65; }
.ai-primary-card { background: radial-gradient(circle at 92% 8%, rgba(87, 169, 255, 0.18), transparent 42%), linear-gradient(145deg, rgba(87, 169, 255, 0.08), transparent 55%), var(--surface); }
.ai-primary-card::after { content: 'AI'; position: absolute; right: 22px; bottom: -24px; font-family: var(--font-mono); font-size: 108px; font-weight: 800; line-height: 1; color: rgba(87, 169, 255, 0.045); pointer-events: none; }
.ai-capability-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.ai-capability-list span, .context-flow span { border: 1px solid var(--accent-line); border-radius: 999px; background: rgba(87, 169, 255, 0.06); color: var(--text-1); font-size: 12px; padding: 7px 11px; }
.context-flow { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.context-flow i { color: var(--cyan); font-style: normal; opacity: 0.65; }
.human-card { background: linear-gradient(145deg, rgba(68, 214, 168, 0.06), transparent 55%), var(--surface); }
.principle-list { display: grid; gap: 15px; margin-top: 20px; padding: 0; list-style: none; }
.principle-list li { display: grid; gap: 4px; padding-left: 18px; position: relative; }
.principle-list li::before { content: ''; position: absolute; left: 0; top: 8px; width: 6px; height: 6px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 12px rgba(87, 169, 255, 0.5); }
.principle-list strong { color: #fff; font-size: 14px; }
.principle-list span { color: var(--text-2); font-size: 13px; line-height: 1.65; }
.about-contact-strip { margin-top: 20px; padding: 24px 28px; display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.about-contact-strip strong { color: #fff; font-size: 16px; }
.about-contact-strip .card-kicker { margin-bottom: 5px; }
.about-contact-links { display: flex; flex-wrap: wrap; gap: 10px 18px; }
.about-contact-links a { font-size: 13px; }

.stack-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.stack-list span {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--text-2);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 5px 12px;
  background: var(--bg);
  transition: border-color 0.25s, color 0.25s;
}
.stack-list span:hover { border-color: var(--accent-line); color: var(--accent); }

/* ---------- 文档二级目录 ---------- */
.toc-group { margin-bottom: 6px; }
.toc-head {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 10px 10px 4px;
}
.toc-group a { padding-left: 24px; }

/* ---------- 贡献者页 ---------- */
.contrib-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.contrib-card { padding: 34px 24px; text-align: center; }
.c-avatar {
  width: 74px; height: 74px;
  margin: 0 auto 18px;
  display: grid; place-items: center;
  border-radius: 50%;
  overflow: hidden;
  background: var(--accent);
}
.c-avatar img {
  width: 100%; height: 100%;
  object-fit: cover;
  display: block;
}
.contrib-card h3 { font-size: 19px; letter-spacing: -0.01em; }
.c-role {
  display: inline-block;
  margin-top: 8px;
  font-size: 12px;
  color: var(--text-2);
  border: 1px solid var(--line-2);
  border-radius: 999px;
  padding: 2px 12px;
}
.c-role.lead {
  color: #04101f;
  font-weight: 600;
  background: var(--accent);
  border-color: transparent;
}
.c-desc { margin-top: 10px; color: var(--text-2); font-size: 13.5px; }

.join-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 36px 40px;
  flex-wrap: wrap;
}
.join-copy { max-width: 560px; }
.join-copy h3 { font-size: 22px; margin-bottom: 10px; letter-spacing: -0.01em; }
.join-copy p { color: var(--text-2); font-size: 14.5px; }
.join-links { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------- 关于页：团队介绍 ---------- */
.team-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.team-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-top: 6px;
}
.team-stat {
  text-align: center;
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 6px;
}
.team-stat .num {
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  color: #fff;
}
.team-stat .label { margin-top: 2px; color: var(--text-3); font-size: 12px; }

.proj-list { margin-top: 20px; display: flex; flex-direction: column; gap: 12px; }
.proj-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 22px;
  transition: border-color 0.25s, transform 0.25s;
}
.proj-item:hover { border-color: var(--accent-line); transform: translateY(-2px); }
.proj-info { display: flex; flex-direction: column; gap: 4px; }
.proj-name { font-family: var(--font-mono); font-weight: 700; font-size: 15px; color: var(--accent); }
.proj-tag {
  font-style: normal;
  font-size: 10.5px;
  color: #f2cc60;
  border: 1px solid rgba(242, 204, 96, 0.4);
  border-radius: 999px;
  padding: 0 7px;
  margin-left: 6px;
}
.proj-desc { color: var(--text-2); font-size: 13.5px; }
.proj-stars {
  font-family: var(--font-mono);
  font-size: 13px;
  color: #f2cc60;
  white-space: nowrap;
}

/* ---------- 滚动渐入 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: 0.08s; }
.reveal[data-delay="2"] { transition-delay: 0.16s; }
.reveal[data-delay="3"] { transition-delay: 0.24s; }

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(14px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .dl-grid { grid-template-columns: repeat(2, 1fr); }
  .contrib-grid { grid-template-columns: repeat(2, 1fr); }
  .team-grid { grid-template-columns: 1fr; }
  .ai-wrap, .ai-cap-grid { grid-template-columns: 1fr; }
  .ai-wrap { gap: 32px; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .about-grid { grid-template-columns: 1fr; }
}

@media (max-width: 767px) {
  .section { padding: 68px 0; }
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 14px 20px 20px;
    background: rgba(8, 9, 13, 0.98);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s, transform 0.25s;
  }
  .nav-links.open { transform: none; opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 12px 14px; font-size: 16px; }
  .nav-cta { margin: 8px 0 0; text-align: center; }
  .stats-bar { grid-template-columns: 1fr; }
  .stats-bar .stat + .stat { border-left: none; border-top: 1px solid var(--line); }
  .dl-grid, .feat-grid, .pillar-grid, .contrib-grid, .ai-cap-grid { grid-template-columns: 1fr; }
  .team-stats { grid-template-columns: repeat(2, 1fr); }
  .join-card { flex-direction: column; align-items: flex-start; }
  .proj-item { flex-direction: column; align-items: flex-start; gap: 8px; }
  .shot-panel.active { grid-template-columns: 1fr; }
  .docs-layout { grid-template-columns: 1fr; gap: 24px; }
  .docs-toc { position: static; }
  .footer-grid { grid-template-columns: 1fr; gap: 22px; }
  .hero { padding: 72px 0 40px; }
  .tl-group li { padding-left: 0; padding-top: 30px; }
  .cl-tag { top: 6px; }
}

/* ---------- 文档中心 Hub ---------- */
.docs-hub { padding: 72px 0 96px; }
.docs-hub-group { margin-bottom: 54px; }
.docs-hub-group > .dg-head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}
.docs-hub-group > .dg-head h2 { font-size: 20px; letter-spacing: -0.01em; }
.docs-hub-group > .dg-head span {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-3);
}
.docs-hub-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
.doc-card {
  display: block;
  padding: 24px 22px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s, background 0.25s;
}
.doc-card:hover {
  border-color: var(--accent-line);
  background: var(--surface-2);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.doc-card .dc-icon {
  width: 42px; height: 42px;
  display: grid; place-items: center;
  border-radius: 11px;
  background: var(--accent-dim);
  border: 1px solid var(--accent-line);
  margin-bottom: 16px;
}
.doc-card .dc-icon svg { width: 21px; height: 21px; stroke: var(--accent); fill: none; }
.doc-card h3 { font-size: 16.5px; color: var(--text); margin-bottom: 8px; letter-spacing: -0.01em; }
.doc-card p { color: var(--text-2); font-size: 14px; line-height: 1.7; margin: 0; }
.doc-card .dc-tags {
  margin-top: 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.doc-card .dc-tags span {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--text-3);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 2px 10px;
}

/* ---------- 文档面包屑 ---------- */
.doc-crumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-3);
  margin-bottom: 22px;
  flex-wrap: wrap;
}
.doc-crumb a { color: var(--text-2); }
.doc-crumb a:hover { color: var(--accent); }
.doc-crumb .sep { color: var(--text-3); opacity: 0.6; }
.doc-crumb .cur { color: var(--text); }

/* ---------- 文档内嵌截图 ---------- */
.doc-figure { margin: 20px 0 8px; }
.doc-shot {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line-2);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: border-color 0.3s, box-shadow 0.3s;
}
.doc-shot:hover { border-color: var(--accent-line); box-shadow: var(--shadow-md); }
.doc-shot .win-head { padding: 9px 14px; }
.doc-shot .win-head i { width: 10px; height: 10px; }
.doc-shot img { display: block; width: 100%; height: auto; }
.doc-figure figcaption {
  margin-top: 10px;
  font-size: 13px;
  color: var(--text-2);
  line-height: 1.6;
  padding-left: 2px;
}
.doc-figure figcaption strong { color: var(--text); font-weight: 600; }
.doc-fig-note {
  border: 1px dashed var(--line-2);
  border-radius: var(--radius);
  padding: 28px 22px;
  text-align: center;
  color: var(--text-3);
  font-size: 13.5px;
  background: var(--bg-2);
}

/* ---------- 功能条目卡片（工具中心页） ---------- */
.feature-block { margin-bottom: 40px; scroll-margin-top: calc(var(--nav-h) + 20px); }
.feature-block > h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  color: var(--text);
  margin-bottom: 6px;
}
.feature-block .fb-status {
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 600;
  border-radius: 6px;
  padding: 2px 8px;
}
.fb-status.live { color: #7ee787; background: rgba(126, 231, 135, 0.1); border: 1px solid rgba(126, 231, 135, 0.3); }
.fb-status.dev { color: #f2cc60; background: rgba(242, 204, 96, 0.1); border: 1px solid rgba(242, 204, 96, 0.3); }
.feature-block > .fb-sub {
  color: var(--text-3);
  font-size: 13px;
  margin-bottom: 12px;
  font-family: var(--font-mono);
}

/* ---------- 文档上一页/下一页 ---------- */
.doc-pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 56px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}
.doc-pager a {
  display: block;
  padding: 16px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  transition: border-color 0.25s, background 0.25s;
}
.doc-pager a:hover { border-color: var(--accent-line); background: var(--surface-2); }
.doc-pager .pg-label { font-size: 12px; color: var(--text-3); font-family: var(--font-mono); }
.doc-pager .pg-title { font-size: 15px; color: var(--text); margin-top: 4px; }
.doc-pager .pg-next { text-align: right; }
.doc-pager .pg-empty { border: none; background: none; pointer-events: none; }

@media (max-width: 860px) {
  .docs-hub-grid { grid-template-columns: 1fr; }
  .doc-pager { grid-template-columns: 1fr; }
  .doc-pager .pg-next { text-align: left; }
  .doc-pager .pg-empty { display: none; }
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001s !important;
    transition-duration: 0.001s !important;
  }
  .reveal { opacity: 1; transform: none; }
  #particles { display: none; }
}


/* ---------- 给所有内测者的一封信 ---------- */
.letter-page { overflow: hidden; }
.letter-hero { position: relative; padding: 138px 0 82px; text-align: center; border-bottom: 1px solid var(--line); }
.letter-hero .container { position: relative; z-index: 1; }
.letter-orb { position: absolute; border-radius: 50%; filter: blur(90px); pointer-events: none; opacity: 0.24; }
.letter-orb-one { width: 460px; height: 460px; top: -180px; left: 7%; background: #3578ff; }
.letter-orb-two { width: 380px; height: 380px; right: 9%; bottom: -220px; background: #8b5cf6; }
.letter-overline { margin-bottom: 22px; color: var(--cyan); font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.22em; }
.letter-hero h1 { margin: 0; color: #fff; font-size: clamp(48px, 8vw, 88px); line-height: 1.05; letter-spacing: -0.055em; }
.letter-deck { max-width: 720px; margin: 28px auto 0; color: var(--text-2); font-size: clamp(17px, 2vw, 21px); line-height: 1.9; }
.letter-meta { display: flex; align-items: center; justify-content: center; gap: 13px; margin-top: 32px; color: var(--text-3); font-family: var(--font-mono); font-size: 12px; }
.letter-meta i { width: 3px; height: 3px; border-radius: 50%; background: var(--cyan); }
.letter-article { max-width: 960px; padding-top: 76px; padding-bottom: 110px; }
.letter-paper { position: relative; padding: clamp(34px, 7vw, 80px); border: 1px solid rgba(255,255,255,0.1); border-radius: 24px; background: linear-gradient(145deg, rgba(255,255,255,0.045), rgba(255,255,255,0.012)); box-shadow: 0 34px 100px rgba(0,0,0,0.24); }
.letter-paper::before { content: ''; position: absolute; top: 0; left: 10%; right: 10%; height: 1px; background: linear-gradient(90deg, transparent, var(--cyan), transparent); opacity: 0.65; }
.letter-paper p { margin: 0 0 22px; color: #b8c0d3; font-size: 16px; line-height: 2.08; }
.letter-paper strong { color: #fff; }
.letter-salutation { color: #fff !important; font-size: 19px !important; }
.letter-lead::first-letter { float: left; margin: 10px 10px 0 0; color: var(--cyan); font-family: Georgia, serif; font-size: 64px; line-height: 0.7; }
.letter-paper h2 { margin: 76px 0 28px; color: #fff; font-size: clamp(24px, 4vw, 34px); line-height: 1.45; letter-spacing: -0.025em; }
.letter-paper h2 span { display: block; margin-bottom: 10px; color: var(--cyan); font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.18em; }
.letter-paper blockquote { margin: 52px 0; padding: 30px 34px; border-left: 3px solid var(--cyan); border-radius: 0 14px 14px 0; background: rgba(87,169,255,0.06); color: #edf6ff; font-size: clamp(19px, 2.6vw, 25px); font-weight: 600; line-height: 1.75; }
.letter-pullquote { margin: 60px -24px; padding: 48px 28px; text-align: center; border-top: 1px solid var(--accent-line); border-bottom: 1px solid var(--accent-line); background: radial-gradient(circle at center, rgba(87,169,255,0.11), transparent 68%); }
.letter-pullquote small { display: block; margin-bottom: 16px; color: var(--cyan); font-family: var(--font-mono); letter-spacing: 0.2em; }
.letter-pullquote strong { font-size: clamp(22px, 3.4vw, 31px); line-height: 1.65; }
.letter-comparison { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; margin: 32px 0 30px; }
.letter-comparison section { padding: 28px; border: 1px solid var(--line); border-radius: 16px; background: rgba(5,8,15,0.45); }
.letter-comparison h3 { margin: 12px 0 22px; color: #fff; font-size: 19px; }
.letter-comparison p { margin-bottom: 15px; font-size: 14px; line-height: 1.8; }
.comparison-icon { color: var(--cyan); font-size: 26px; }
.letter-comparison .comparison-good, .letter-comparison .comparison-gap { margin-bottom: 5px; color: #fff; font-size: 12px; font-family: var(--font-mono); letter-spacing: 0.08em; }
.letter-comparison .comparison-good { color: #6ee7b7; }
.letter-comparison .comparison-gap { color: #fbbf77; }
.letter-closing { margin-top: 70px; padding-top: 34px; border-top: 1px solid var(--line); text-align: right; }
.letter-closing p { color: #fff; font-size: 18px; }
.letter-closing strong, .letter-closing span { display: block; }
.letter-closing strong { margin-top: 28px; color: #fff; font-size: 25px; }
.letter-closing span { margin-top: 5px; color: var(--text-3); font-family: var(--font-mono); font-size: 12px; }
.letter-afterword { margin-top: 28px; padding: 44px; text-align: center; border: 1px solid var(--accent-line); border-radius: 20px; background: radial-gradient(circle at 50% 0, rgba(87,169,255,0.13), transparent 62%), var(--surface); }
.letter-afterword > span { color: var(--cyan); font-family: var(--font-mono); font-size: 11px; letter-spacing: 0.19em; }
.letter-afterword h2 { margin: 14px 0 10px; color: #fff; font-size: clamp(25px, 4vw, 36px); }
.letter-afterword p { color: var(--text-2); }
.letter-actions { display: flex; justify-content: center; gap: 12px; margin-top: 26px; }

@media (max-width: 767px) {
  .letter-hero { padding: 108px 0 58px; }
  .letter-deck br { display: none; }
  .letter-meta { flex-direction: column; gap: 7px; }
  .letter-meta i { display: none; }
  .letter-article { padding-top: 34px; padding-bottom: 70px; }
  .letter-paper { border-radius: 16px; }
  .letter-paper h2 { margin-top: 58px; }
  .letter-paper blockquote { margin: 38px 0; padding: 24px 22px; }
  .letter-pullquote { margin: 42px -12px; padding: 36px 16px; }
  .letter-pullquote br { display: none; }
  .letter-comparison { grid-template-columns: 1fr; }
  .letter-afterword { padding: 34px 22px; }
  .letter-actions { flex-direction: column; }
}

/* ---------- 导航：写给内测者的信 ---------- */
.nav-links .nav-letter {
  position: relative;
  color: #ffd78a;
  border: 1px solid rgba(255, 197, 92, 0.2);
  background: linear-gradient(135deg, rgba(255, 190, 74, 0.1), rgba(255, 133, 82, 0.055));
  box-shadow: inset 0 0 18px rgba(255, 196, 88, 0.025);
}
.nav-links .nav-letter::before {
  content: '';
  width: 6px;
  height: 6px;
  margin-right: 7px;
  display: inline-block;
  vertical-align: 1px;
  border-radius: 50%;
  background: #ffc75f;
  box-shadow: 0 0 10px rgba(255, 199, 95, 0.72);
}
.nav-links .nav-letter:hover {
  color: #fff1c9;
  border-color: rgba(255, 205, 112, 0.48);
  background: linear-gradient(135deg, rgba(255, 190, 74, 0.17), rgba(255, 123, 75, 0.09));
  box-shadow: 0 0 24px rgba(255, 174, 70, 0.11), inset 0 0 18px rgba(255, 205, 120, 0.04);
}
.nav-links .nav-letter.active {
  color: #fff5d8;
  border-color: rgba(255, 211, 126, 0.58);
  background: linear-gradient(135deg, rgba(255, 196, 84, 0.23), rgba(255, 126, 75, 0.12));
  box-shadow: 0 0 28px rgba(255, 181, 71, 0.14), inset 0 0 20px rgba(255, 222, 150, 0.055);
}