/* ==========================================================================
   步步盾 BBDUN — 全站样式
   设计语言：清透白底 + 青蓝渐变（防护）+ 琥珀金（认证/核心）
   视觉母题：层叠盾牌 / 阶梯递进 / 流量轨迹
   ========================================================================== */

/* ---------------------------------------------------------------- tokens */
:root {
  /* 底色层：从纯白到极浅蓝灰（浅色主题） */
  --ink-900: #FFFFFF;
  --ink-850: #FBFCFE;
  --ink-800: #F5F8FD;
  --ink-700: #EEF3FB;
  --ink-600: #E4EBF7;
  --ink-500: #D7E1F1;

  /* 主色：青蓝（防护）— 略加深以保证白底对比度 */
  --brand-400: #0EA5E9;
  --brand-500: #0284C7;
  --brand-600: #0369A1;
  --brand-700: #075985;

  /* 辅色：靛蓝（信任） */
  --indigo-400: #6366F1;
  --indigo-500: #4F46E5;
  --indigo-600: #4338CA;

  /* 点缀：琥珀金（认证 / 核心 / 热门） */
  --amber-400: #F59E0B;
  --amber-500: #D97706;

  /* 语义 */
  --ok-400: #059669;
  --warn-400: #D97706;
  --danger-400: #DC2626;

  /* 文本：浅底需要更深的前景色 */
  --text-hi: #0B1B36;
  --text-mid: #3D5478;
  --text-low: #5B7095;
  --text-dim: #8496B4;

  /* 线与面 */
  --line: rgba(13, 42, 82, 0.10);
  --line-str: rgba(13, 42, 82, 0.20);
  --surface: rgba(255, 255, 255, 0.88);
  --surface-hi: rgba(255, 255, 255, 0.96);

  /* 渐变 */
  --grad-brand: linear-gradient(135deg, var(--brand-400) 0%, var(--brand-600) 55%, var(--indigo-600) 100%);
  --grad-text: linear-gradient(100deg, #0B1B36 0%, #1D4E89 40%, var(--brand-500) 100%);
  --grad-gold: linear-gradient(135deg, var(--amber-400) 0%, var(--amber-500) 100%);

  /* 圆角 */
  --r-sm: 8px;
  --r-md: 14px;
  --r-lg: 20px;
  --r-xl: 28px;
  --r-full: 999px;

  /* 阴影：浅色主题用低透明度冷灰蓝 */
  --sh-sm: 0 1px 3px rgba(13, 42, 82, 0.08);
  --sh-md: 0 8px 24px rgba(13, 42, 82, 0.10);
  --sh-lg: 0 20px 48px rgba(13, 42, 82, 0.14);
  --sh-glow: 0 0 0 1px rgba(14, 165, 233, 0.30), 0 10px 32px rgba(14, 165, 233, 0.18);

  /* 尺寸 */
  --container: 1240px;
  --nav-h: 72px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  /* 语义化的纯色面（浅色主题专用） */
  --bg-page: #F7F9FD;
  --bg-card: #FFFFFF;
  --bg-inset: #F4F7FC;
  --nav-bg: rgba(255, 255, 255, 0.82);
  --nav-bg-solid: rgba(255, 255, 255, 0.96);
  --on-brand: #FFFFFF;
  --tint-brand: rgba(14, 165, 233, 0.10);
  --tint-brand-str: rgba(14, 165, 233, 0.20);
}

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

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

body {
  margin: 0;
  position: relative;          /* 作为 .bg-decor / .bg-grid 的定位上下文 */
  background: var(--bg-page);
  color: var(--text-mid);
  font-family: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI",
               "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5 {
  margin: 0 0 0.5em;
  color: var(--text-hi);
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: -0.015em;
}

h1 { font-size: clamp(2.1rem, 4.6vw, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.6rem, 3.1vw, 2.35rem); font-weight: 800; }
h3 { font-size: clamp(1.1rem, 1.7vw, 1.3rem); }
h4 { font-size: 1rem; }

p  { margin: 0 0 1em; }
ul { margin: 0; padding: 0; list-style: none; }
a  { color: var(--brand-400); text-decoration: none; transition: color 0.22s var(--ease); }
a:hover { color: var(--brand-500); }

img, svg { max-width: 100%; }
img { height: auto; display: block; }

button, input, select, textarea { font: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--brand-400);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection { background: rgba(14, 165, 233, 0.3); color: #fff; }

/* ------------------------------------------------------------- layout */
.container {
  width: min(100% - 40px, var(--container));
  margin-inline: auto;
}

.section {
  position: relative;
  padding: clamp(64px, 8vw, 112px) 0;
}

.section-tight { padding: clamp(48px, 5vw, 72px) 0; }

.section-head {
  max-width: 760px;
  margin: 0 auto clamp(40px, 5vw, 64px);
  text-align: center;
}

.section-head p {
  color: var(--text-mid);
  font-size: 1.02rem;
  margin-bottom: 0;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 15px;
  margin-bottom: 18px;
  border: 1px solid var(--line-str);
  border-radius: var(--r-full);
  background: rgba(14, 165, 233, 0.07);
  color: var(--brand-400);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
}

.eyebrow::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--brand-400);
  box-shadow: 0 0 10px var(--brand-400);
}

.section-head h2 { margin-bottom: 14px; }
.text-grad {
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* --------------------------------------------------------- background */
/* 注意：装饰层随文档流铺满而非 fixed —— fixed 在超长页面下会让下方区域露白。 */
.bg-decor {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  min-height: 100%;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(ellipse 900px 620px at 78% 2%, rgba(14, 165, 233, 0.10), transparent 62%),
    radial-gradient(ellipse 760px 540px at 8% 18%, rgba(79, 70, 229, 0.07), transparent 60%),
    radial-gradient(ellipse 900px 620px at 50% 46%, rgba(6, 182, 212, 0.06), transparent 64%),
    linear-gradient(180deg, #FFFFFF 0%, var(--ink-850) 26%, var(--ink-800) 62%, var(--ink-850) 100%);
}

/* 细网格纹理 */
.bg-grid {
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  min-height: 100%;
  z-index: -1;
  pointer-events: none;
  opacity: 0.5;
  background-image:
    linear-gradient(rgba(13, 42, 82, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(13, 42, 82, 0.045) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: linear-gradient(180deg, #000 0%, rgba(0,0,0,0.45) 55%, transparent 100%);
  -webkit-mask-image: linear-gradient(180deg, #000 0%, rgba(0,0,0,0.45) 55%, transparent 100%);
}

/* ---------------------------------------------------------------- skip */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 12px 20px;
  background: var(--brand-600);
  color: #fff;
  border-radius: 0 0 var(--r-sm) 0;
}
.skip-link:focus { left: 0; color: #fff; }

/* ================================================================ header */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: var(--nav-bg);
  backdrop-filter: blur(18px) saturate(1.6);
  -webkit-backdrop-filter: blur(18px) saturate(1.6);
  border-bottom: 1px solid transparent;
  transition: background 0.3s var(--ease), border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.site-header.is-stuck {
  background: var(--nav-bg-solid);
  border-bottom-color: var(--line);
  box-shadow: var(--sh-md);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  width: min(100% - 40px, var(--container));
}

/* 阅读进度条 */
.header-progress {
  position: absolute;
  left: 0; bottom: -1px;
  height: 2px;
  width: 0%;
  background: var(--grad-brand);
  box-shadow: 0 0 12px rgba(14, 165, 233, 0.7);
  transition: width 0.1s linear;
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  flex-shrink: 0;
  color: var(--text-hi);
}

.brand-mark {
  width: 40px; height: 40px;
  transition: transform 0.4s var(--ease);
}

.brand:hover .brand-mark { transform: rotate(-6deg) scale(1.06); }

.brand-text { display: flex; flex-direction: column; line-height: 1.12; }
.brand-text strong {
  font-size: 1.16rem;
  font-weight: 800;
  letter-spacing: 0.03em;
  color: var(--text-hi);
}
.brand-text em {
  font-style: normal;
  font-size: 0.605rem;
  font-weight: 600;
  letter-spacing: 0.185em;
  color: var(--text-low);
}

/* 头部品牌：只留中文名，与 logo 垂直居中对齐 */
.site-header .brand { gap: 12px; }
.site-header .brand-text { line-height: 1; }
.site-header .brand-text strong {
  font-size: 1.22rem;
  letter-spacing: 0.06em;
}
.site-header .brand-text em { display: none; }

/* 主导航 */
.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

.main-nav a {
  position: relative;
  padding: 8px 14px;
  border-radius: var(--r-sm);
  color: var(--text-mid);
  font-size: 0.935rem;
  font-weight: 500;
  white-space: nowrap;
  transition: color 0.2s var(--ease), background 0.2s var(--ease);
}

.main-nav a:hover {
  color: var(--text-hi);
  background: rgba(13, 42, 82, 0.05);
}

.main-nav a.is-active { color: var(--brand-400); }

.main-nav a.is-active::after {
  content: "";
  position: absolute;
  left: 14px; right: 14px;
  bottom: 1px;
  height: 2px;
  border-radius: 2px;
  background: var(--grad-brand);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  width: 42px; height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  background: var(--surface);
  cursor: pointer;
  position: relative;
}

.nav-toggle span {
  position: absolute;
  left: 11px;
  width: 18px; height: 2px;
  border-radius: 2px;
  background: var(--text-hi);
  transition: transform 0.3s var(--ease), opacity 0.2s var(--ease);
}
.nav-toggle span:nth-child(1) { top: 14px; }
.nav-toggle span:nth-child(2) { top: 20px; }
.nav-toggle span:nth-child(3) { top: 26px; }

.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ================================================================ buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border: 1px solid transparent;
  border-radius: var(--r-full);
  font-size: 0.94rem;
  font-weight: 600;
  line-height: 1.2;
  white-space: nowrap;
  cursor: pointer;
  transition: transform 0.22s var(--ease), box-shadow 0.22s var(--ease),
              background 0.22s var(--ease), border-color 0.22s var(--ease), color 0.22s var(--ease);
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn-primary {
  background: var(--grad-brand);
  color: #fff;
  box-shadow: 0 8px 26px rgba(14, 165, 233, 0.34);
}
.btn-primary:hover {
  color: #fff;
  box-shadow: 0 14px 36px rgba(14, 165, 233, 0.5);
}

.btn-ghost {
  border-color: var(--line-str);
  background: var(--surface);
  color: var(--text-hi);
}
.btn-ghost:hover {
  border-color: var(--brand-400);
  color: var(--brand-400);
  background: rgba(14, 165, 233, 0.1);
}

.btn-outline {
  border-color: var(--line-str);
  background: transparent;
  color: var(--text-mid);
}
.btn-outline:hover {
  border-color: var(--brand-400);
  color: var(--brand-400);
}

.btn-sm { padding: 9px 17px; font-size: 0.87rem; }
.btn-lg { padding: 15px 32px; font-size: 1rem; }

.btn-block { width: 100%; }

/* ================================================================== hero */
.hero {
  position: relative;
  padding: calc(var(--nav-h) + clamp(56px, 8vw, 96px)) 0 clamp(64px, 8vw, 110px);
  overflow: hidden;
}

/* 流动网格背景 */
.hero-mesh {
  position: absolute;
  inset: -20% -10% auto;
  height: 130%;
  pointer-events: none;
  background:
    radial-gradient(circle at 22% 34%, rgba(14, 165, 233, 0.16), transparent 42%),
    radial-gradient(circle at 78% 20%, rgba(129, 140, 248, 0.15), transparent 44%),
    radial-gradient(circle at 52% 78%, rgba(6, 182, 212, 0.11), transparent 46%);
  filter: blur(28px);
}

/* 盾牌轮廓装饰 */
.hero-shield {
  position: absolute;
  top: 46%;
  right: -160px;
  width: min(620px, 62vw);
  transform: translateY(-50%);
  pointer-events: none;
  opacity: 0.15;
}

.hero-shield svg { width: 100%; height: auto; }

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(0, 0.92fr);
  gap: clamp(36px, 5vw, 72px);
  align-items: center;
}

.hero-copy { max-width: 640px; }

.hero-title {
  margin-bottom: 20px;
  font-weight: 800;
  letter-spacing: -0.025em;
}

.hero-title .line {
  display: block;
  white-space: nowrap;
}

@media (max-width: 620px) {
  .hero-title .line { white-space: normal; }
}

.hero-title .hl {
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-lead {
  font-size: clamp(1rem, 1.35vw, 1.12rem);
  color: var(--text-mid);
  margin-bottom: 30px;
  max-width: 560px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 44px;
}

/* Hero 数据条 */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  overflow: hidden;
}

.hero-stat {
  padding: 20px 18px;
  background: var(--ink-800);
  text-align: center;
}

.hero-stat b {
  display: block;
  font-size: clamp(1.3rem, 2.1vw, 1.7rem);
  font-weight: 800;
  line-height: 1.2;
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-stat span {
  display: block;
  margin-top: 4px;
  font-size: 0.775rem;
  color: var(--text-low);
  letter-spacing: 0.02em;
}

/* 移动端数据条：直接显示，不依赖滚动进场动画 */
@media (max-width: 860px) {
  .hero-stats .hero-stat {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ------------------------------------------------------- 攻防演示面板 */
.sim {
  position: relative;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface-hi);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: var(--sh-lg);
}

.sim-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 14px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.sim-title {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-hi);
}

.sim-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--ok-400);
  box-shadow: 0 0 10px var(--ok-400);
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: 0.45; transform: scale(0.82); }
}

.sim-state {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--brand-400);
}

/* 流量轨 */
.sim-track {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
  padding: 14px 0;
  border-bottom: 1px dashed var(--line);
}
.sim-track:last-of-type { border-bottom: 0; }

.sim-side { min-width: 0; }

.sim-side-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.735rem;
  color: var(--text-low);
  margin-bottom: 8px;
  letter-spacing: 0.02em;
}

.sim-meter {
  height: 9px;
  border-radius: var(--r-full);
  background: rgba(120, 165, 235, 0.1);
  overflow: hidden;
}

.sim-meter i {
  display: block;
  height: 100%;
  width: 0%;
  min-width: 3px;
  border-radius: inherit;
  transition: width 0.55s var(--ease);
}

.meter-attack i { background: linear-gradient(90deg, var(--danger-400), #DC2626); }
.meter-normal i { background: linear-gradient(90deg, var(--brand-400), var(--indigo-500)); }
.meter-block  i { background: linear-gradient(90deg, var(--ok-400), #10B981); }
.meter-pass   i { background: var(--grad-brand); }

.sim-node {
  display: grid;
  place-items: center;
  width: 54px; height: 54px;
  border: 1px solid var(--line-str);
  border-radius: var(--r-md);
  background: rgba(248, 250, 253, 0.92);
  flex-shrink: 0;
}

.sim-node img { width: 38px; height: 38px; }

.sim-value {
  display: flex;
  align-items: baseline;
  gap: 3px;
  margin-top: 7px;
  font-size: 0.78rem;
  color: var(--text-mid);
}

.sim-value b {
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--text-hi);
  font-variant-numeric: tabular-nums;
}

.sim-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.sim-legend span {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.735rem;
  color: var(--text-low);
}

.sim-legend i {
  width: 9px; height: 9px;
  border-radius: 3px;
  flex-shrink: 0;
}

/* ============================================================== pillars */
.pillars {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}

.pillar {
  position: relative;
  padding: 34px 30px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface);
  overflow: hidden;
  transition: transform 0.34s var(--ease), border-color 0.34s var(--ease), box-shadow 0.34s var(--ease);
}

.pillar::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: 3px;
  background: var(--grad-brand);
  opacity: 0;
  transition: opacity 0.34s var(--ease);
}

.pillar:hover {
  transform: translateY(-6px);
  border-color: rgba(14, 165, 233, 0.36);
  box-shadow: var(--sh-glow);
}

.pillar:hover::before { opacity: 1; }

.pillar-tag {
  position: absolute;
  top: 22px; right: 24px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--brand-400);
  opacity: 0.55;
}

.pillar-icon {
  display: grid;
  place-items: center;
  width: 56px; height: 56px;
  margin-bottom: 20px;
  border: 1px solid rgba(14, 165, 233, 0.28);
  border-radius: var(--r-md);
  background: rgba(14, 165, 233, 0.09);
  color: var(--brand-400);
  transition: transform 0.34s var(--ease);
}

.pillar:hover .pillar-icon {
  transform: scale(1.06) rotate(-4deg);
  box-shadow: 0 8px 24px rgba(14, 165, 233, 0.28);
}

.pillar h3 { margin-bottom: 10px; }
.pillar p  { color: var(--text-mid); font-size: 0.935rem; margin-bottom: 18px; }

.pillar-points { display: grid; gap: 8px; }

.pillar-points li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.855rem;
  color: var(--text-low);
}

.pillar-points svg { color: var(--ok-400); flex-shrink: 0; }

/* ============================================================== features */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(268px, 1fr));
  gap: 18px;
}

.feature {
  padding: 26px 24px;
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--surface);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease), background 0.3s var(--ease);
}

.feature:hover {
  transform: translateY(-4px);
  border-color: var(--line-str);
  background: var(--surface-hi);
}

.feature-icon {
  display: grid;
  place-items: center;
  width: 44px; height: 44px;
  margin-bottom: 16px;
  border-radius: var(--r-sm);
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.16), rgba(99, 102, 241, 0.12));
  color: var(--brand-400);
}

.feature h3 { font-size: 1.02rem; margin-bottom: 8px; }
.feature p  { font-size: 0.875rem; color: var(--text-low); margin: 0; }

/* ================================================================ nodes */
.node-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(248px, 1fr));
  gap: 20px;
}

.node-card {
  position: relative;
  padding: 26px 24px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface);
  overflow: hidden;
  transition: transform 0.32s var(--ease), border-color 0.32s var(--ease), box-shadow 0.32s var(--ease);
}

.node-card:hover {
  transform: translateY(-5px);
  border-color: rgba(14, 165, 233, 0.34);
  box-shadow: var(--sh-md);
}

.node-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 18px;
}

.node-city {
  display: flex;
  align-items: center;
  gap: 11px;
}

.node-flag {
  display: grid;
  place-items: center;
  width: 42px; height: 42px;
  border: 1px solid var(--line-str);
  border-radius: var(--r-sm);
  background: rgba(246, 249, 253, 0.9);
  font-size: 0.735rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--brand-400);
}

.node-city h3 { font-size: 1.05rem; margin: 0; }
.node-city span { font-size: 0.775rem; color: var(--text-dim); }

.node-status {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--r-full);
  background: rgba(52, 211, 153, 0.1);
  color: var(--ok-400);
  font-size: 0.72rem;
  font-weight: 600;
}

.node-status::before {
  content: "";
  width: 5px; height: 5px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 0 0 8px currentColor;
}

.node-delay {
  display: flex;
  align-items: baseline;
  gap: 5px;
  margin-bottom: 6px;
}

.node-delay b {
  font-size: 1.55rem;
  font-weight: 800;
  color: var(--text-hi);
  font-variant-numeric: tabular-nums;
}

.node-delay span { font-size: 0.775rem; color: var(--text-low); }

.node-line {
  font-size: 0.775rem;
  color: var(--text-dim);
  margin-bottom: 16px;
}

/* 负载条 */
.node-load { display: grid; gap: 6px; }

.node-load-head {
  display: flex;
  justify-content: space-between;
  font-size: 0.735rem;
  color: var(--text-dim);
}

.node-load-bar {
  height: 5px;
  border-radius: var(--r-full);
  background: rgba(120, 165, 235, 0.1);
  overflow: hidden;
}

.node-load-bar i {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--grad-brand);
  transition: width 1s var(--ease);
}

/* =============================================================== pricing */
.plans {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(268px, 1fr));
  gap: 22px;
  align-items: stretch;
}

.plan {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 32px 28px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface);
  transition: transform 0.32s var(--ease), border-color 0.32s var(--ease), box-shadow 0.32s var(--ease);
}

.plan:hover {
  transform: translateY(-6px);
  border-color: var(--line-str);
  box-shadow: var(--sh-md);
}

/* 热门标记 */
.plan.is-hot {
  border-color: rgba(245, 158, 11, 0.42);
  background: linear-gradient(180deg, rgba(245, 158, 11, 0.07) 0%, var(--surface) 40%);
  box-shadow: 0 18px 48px rgba(245, 158, 11, 0.1);
}

.plan.is-hot:hover { border-color: rgba(245, 158, 11, 0.7); }

.plan-flag {
  position: absolute;
  top: -1px; right: 26px;
  padding: 5px 14px;
  border-radius: 0 0 var(--r-sm) var(--r-sm);
  background: var(--grad-gold);
  color: #FFFFFF;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.05em;
}

.plan-name {
  font-size: 1.22rem;
  font-weight: 800;
  color: var(--text-hi);
  margin-bottom: 4px;
}

.plan-for {
  font-size: 0.815rem;
  color: var(--text-dim);
  margin-bottom: 22px;
}

.plan-price {
  display: flex;
  align-items: baseline;
  gap: 7px;
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.plan-price b {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1;
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  font-variant-numeric: tabular-nums;
}

.plan.is-hot .plan-price b {
  background: var(--grad-gold);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.plan-price span { font-size: 0.85rem; color: var(--text-low); }

/* 规格表 */
.plan-specs {
  display: grid;
  gap: 12px;
  margin-bottom: 24px;
}

.plan-spec {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.875rem;
}

.plan-spec dt { color: var(--text-low); }
.plan-spec dd {
  margin: 0;
  font-weight: 600;
  color: var(--text-hi);
  text-align: right;
}

/* 功能清单 */
.plan-feats {
  display: grid;
  gap: 10px;
  margin-bottom: 26px;
  flex-grow: 1;
}

.plan-feats li {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  font-size: 0.855rem;
  color: var(--text-mid);
}

.plan-feats svg { color: var(--ok-400); flex-shrink: 0; margin-top: 3px; }
.plan-feats .miss { color: var(--text-dim); }
.plan-feats .miss svg { color: var(--text-dim); }

/* ================================================================ scenes */
.scenes {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.scene {
  padding: 28px 26px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

.scene:hover { transform: translateY(-4px); border-color: var(--line-str); }

.scene-icon {
  display: grid;
  place-items: center;
  width: 48px; height: 48px;
  margin-bottom: 17px;
  border-radius: var(--r-md);
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.15), rgba(129, 140, 248, 0.1));
  color: var(--brand-400);
}

.scene h3 { font-size: 1.05rem; margin-bottom: 8px; }
.scene p  { font-size: 0.875rem; color: var(--text-low); margin-bottom: 14px; }

.scene-cfg {
  padding-top: 13px;
  border-top: 1px dashed var(--line);
  font-size: 0.78rem;
  color: var(--brand-400);
  font-weight: 500;
}

/* =============================================================== process */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(238px, 1fr));
  gap: 20px;
  counter-reset: step;
}

.step {
  position: relative;
  padding: 30px 26px;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  background: var(--surface);
}

.step-no {
  font-size: 2.1rem;
  font-weight: 800;
  line-height: 1;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 14px;
  opacity: 0.9;
}

.step h3 { font-size: 1.02rem; margin-bottom: 9px; }
.step p  { font-size: 0.865rem; color: var(--text-low); margin-bottom: 14px; }

.step-tag {
  display: inline-flex;
  padding: 4px 11px;
  border-radius: var(--r-full);
  background: rgba(14, 165, 233, 0.1);
  color: var(--brand-400);
  font-size: 0.735rem;
  font-weight: 600;
}

/* ================================================================== faq */
.faq-list {
  display: grid;
  gap: 12px;
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  background: var(--surface);
  overflow: hidden;
  transition: border-color 0.26s var(--ease), background 0.26s var(--ease);
}

.faq-item[open] {
  border-color: rgba(14, 165, 233, 0.32);
  background: var(--surface-hi);
}

.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 24px;
  cursor: pointer;
  list-style: none;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-hi);
  transition: color 0.2s var(--ease);
}

.faq-q::-webkit-details-marker { display: none; }
.faq-q:hover { color: var(--brand-400); }

.faq-q::after {
  content: "";
  width: 18px; height: 18px;
  flex-shrink: 0;
  background:
    linear-gradient(var(--brand-400), var(--brand-400)) center / 100% 2px no-repeat,
    linear-gradient(var(--brand-400), var(--brand-400)) center / 2px 100% no-repeat;
  transition: transform 0.3s var(--ease);
}

.faq-item[open] .faq-q::after { transform: rotate(45deg); }

.faq-a {
  padding: 0 24px 22px;
  font-size: 0.905rem;
  color: var(--text-mid);
  line-height: 1.8;
}

/* ================================================================ footer */
.site-footer {
  position: relative;
  padding-top: clamp(56px, 6vw, 80px);
  margin-top: clamp(48px, 6vw, 80px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0) 0%, var(--ink-900) 100%);
}

/* 页脚 CTA */
.footer-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 28px;
  padding: 36px 40px;
  margin-bottom: clamp(44px, 5vw, 64px);
  border: 1px solid rgba(14, 165, 233, 0.24);
  border-radius: var(--r-xl);
  background:
    radial-gradient(ellipse 70% 130% at 8% 0%, rgba(14, 165, 233, 0.14), transparent 62%),
    var(--surface);
}

.footer-cta-text h2 { font-size: clamp(1.4rem, 2.4vw, 1.9rem); margin-bottom: 8px; }
.footer-cta-text p  { margin: 0; color: var(--text-mid); font-size: 0.945rem; }

.footer-cta-actions { display: flex; flex-wrap: wrap; gap: 13px; }

/* 页脚栅格 */
.footer-grid {
  display: grid;
  grid-template-columns: 1.7fr repeat(3, 1fr);
  gap: 40px;
  padding-bottom: 44px;
}

.footer-col h4 {
  margin-bottom: 16px;
  font-size: 0.865rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: var(--text-low);
}

.footer-col ul { display: grid; gap: 11px; }
.footer-col a  { color: var(--text-mid); font-size: 0.895rem; }
.footer-col a:hover { color: var(--brand-400); }

.footer-desc {
  margin: 16px 0;
  font-size: 0.875rem;
  color: var(--text-low);
  max-width: 340px;
}

.footer-badges { display: flex; flex-wrap: wrap; gap: 8px; }

.mini-badge {
  padding: 4px 11px;
  border: 1px solid var(--line);
  border-radius: var(--r-full);
  background: rgba(14, 165, 233, 0.06);
  color: var(--brand-400);
  font-size: 0.735rem;
  font-weight: 600;
}

.footer-contact li {
  display: flex;
  gap: 12px;
  font-size: 0.865rem;
}

.footer-contact span {
  flex-shrink: 0;
  width: 38px;
  color: var(--text-dim);
}

/* 页脚底栏 */
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
  padding: 22px 0 30px;
  border-top: 1px solid var(--line);
  font-size: 0.815rem;
  color: var(--text-dim);
}

.footer-bottom p { margin: 0; }

.footer-legal { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; }
.footer-legal a { color: var(--text-dim); }
.footer-legal a:hover { color: var(--brand-400); }
.footer-legal .dot { opacity: 0.4; }

/* 悬浮客服按钮 */
.fab-tg {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 90;
  display: grid;
  place-items: center;
  width: 52px; height: 52px;
  border-radius: 50%;
  background: linear-gradient(135deg, #2AABEE, #229ED9);
  color: #fff;
  box-shadow: 0 10px 30px rgba(34, 158, 217, 0.42);
  transition: transform 0.28s var(--ease), box-shadow 0.28s var(--ease);
}

.fab-tg:hover {
  color: #fff;
  transform: translateY(-3px) scale(1.05);
  box-shadow: 0 16px 38px rgba(34, 158, 217, 0.56);
}

/* ======================================================= reveal on scroll */
[data-reveal] {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

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

[data-reveal-delay="1"] { transition-delay: 0.08s; }
[data-reveal-delay="2"] { transition-delay: 0.16s; }
[data-reveal-delay="3"] { transition-delay: 0.24s; }
[data-reveal-delay="4"] { transition-delay: 0.32s; }
[data-reveal-delay="5"] { transition-delay: 0.40s; }
[data-reveal-delay="6"] { transition-delay: 0.48s; }

/* 无 JS 时兜底显示 */
.no-js [data-reveal] { opacity: 1; transform: none; }

/* ============================================================== responsive */
@media (max-width: 1080px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-copy { max-width: 720px; }
  .hero-shield { opacity: 0.08; right: -240px; width: 560px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 34px; }
}

@media (max-width: 860px) {
  :root { --nav-h: 64px; }

  /* 窄屏压缩头部：保留图标 + 中文品牌名，隐藏英文副标，避免与展开面板互相挤压 */
  .header-inner { gap: 12px; }

  .brand-text { display: flex; }

  .site-header .brand-text strong {
    font-size: 1.16rem;
    letter-spacing: 0.08em;
    white-space: nowrap;
  }

  .brand-text em { display: none; }

  .brand-mark { width: 36px; height: 36px; }

  /* 移动端：汉堡按钮固定靠右（面板脱离文档流后不能依赖 margin-left:auto） */
  .header-actions {
    margin-left: auto;
    flex-shrink: 0;
  }

  .main-nav {
    position: fixed;
    top: var(--nav-h);
    /* 全宽下拉，内容右对齐：既不遮挡 logo，菜单项又靠右 */
    left: 0;
    right: 0;
    width: 100%;
    max-width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 10px 14px 20px;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--line);
    border-radius: 0 0 var(--r-lg) var(--r-lg);
    box-shadow: var(--sh-lg);
    transform: translateY(-14px);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.3s var(--ease), opacity 0.3s var(--ease), visibility 0.3s;
  }

  .main-nav.is-open {
    transform: none;
    opacity: 1;
    visibility: visible;
  }

  .main-nav a {
    display: flex;
    align-items: center;
    /* 左对齐保证可读性；面板右对齐由 header-actions 的 margin-left:auto 实现 */
    padding: 13px 14px;
    border-radius: var(--r-sm);
    border-bottom: 1px solid var(--line);
    font-size: 0.98rem;
    text-align: left;
  }

  .main-nav a:last-child { border-bottom: 0; }

  .main-nav a:hover { background: var(--tint-brand); }

  .main-nav a.is-active {
    background: var(--tint-brand);
    color: var(--brand-600);
    font-weight: 600;
  }

  .main-nav a.is-active::after { display: none; }

  .nav-toggle { display: grid; place-items: center; }

  .hide-sm { display: none; }

  .hero-stats { grid-template-columns: repeat(2, 1fr); }

  .footer-cta {
    flex-direction: column;
    align-items: flex-start;
    padding: 30px 26px;
  }

  .footer-grid { grid-template-columns: 1fr; gap: 30px; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 520px) {
  .container { width: calc(100% - 32px); }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .btn { width: 100%; }
  .plans, .pillars, .features, .scenes, .steps, .node-grid {
    grid-template-columns: 1fr;
  }
  .plan { padding: 28px 22px; }
  .plan-price b { font-size: 2.2rem; }
  .sim { padding: 18px; }
  .fab-tg { right: 16px; bottom: 16px; width: 48px; height: 48px; }
}

/* ============================================================== a11y/motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
}

/* 打印 */
@media print {
  .site-header, .fab-tg, .bg-decor, .bg-grid, .site-footer { display: none !important; }
  body { background: #fff; color: #000; }
}