/* ============================================================
   k-ai 静态站 · 科技感深色主题 v2
   ============================================================ */

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

:root {
  --bg-0: #05070d;
  --bg-1: #0a0e27;
  --bg-2: #131838;
  --bg-3: #1a2245;
  --line: rgba(255, 255, 255, 0.08);
  --line-h: rgba(255, 255, 255, 0.18);
  --text: #e6e8ee;
  --text-dim: #9097a8;
  --text-mute: #5f6677;
  --cyan: #00d4ff;
  --purple: #7c4dff;
  --pink: #ff5e9d;
  --green: #00d49a;
  --yellow: #ffc857;
  --orange: #ff8a3d;
  --grad: linear-gradient(135deg, #00d4ff 0%, #7c4dff 100%);
  --grad-warm: linear-gradient(135deg, #ff8a3d 0%, #ff5e9d 100%);
  --grad-cool: linear-gradient(135deg, #00d4ff 0%, #00d49a 100%);
  --shadow-glow: 0 0 40px rgba(0, 212, 255, 0.25);
  --shadow-glow-purple: 0 0 40px rgba(124, 77, 255, 0.25);
}

html, body {
  background: var(--bg-0);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  scroll-behavior: smooth;
}

a { color: var(--cyan); text-decoration: none; transition: color .2s; }
a:hover { color: #66e8ff; }
code {
  font-family: "JetBrains Mono", "SF Mono", Consolas, monospace;
  font-size: 0.86em;
  background: rgba(0, 212, 255, 0.1);
  color: #aef0ff;
  padding: 1px 6px;
  border-radius: 3px;
}
strong { color: #fff; font-weight: 600; }

/* ============================================================
   顶部进度条
   ============================================================ */
.page-progress {
  position: fixed; top: 0; left: 0; height: 2px;
  background: var(--grad); z-index: 200;
  width: 0%; transition: width 0.1s linear;
  box-shadow: 0 0 10px var(--cyan);
}

/* ============================================================
   背景层
   ============================================================ */
.bg-grid {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, #000 30%, transparent 80%);
}
.bg-noise {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
.bg-glow {
  position: fixed; z-index: 0; pointer-events: none;
  width: 800px; height: 800px;
  border-radius: 50%;
  filter: blur(140px);
  opacity: 0.35;
  animation: glow-drift 30s ease-in-out infinite alternate;
}
.bg-glow-1 { top: -200px; left: -200px; background: var(--cyan); }
.bg-glow-2 { top: 30%; right: -300px; background: var(--purple); animation-delay: -10s; }
.bg-glow-3 { bottom: -300px; left: 30%; background: var(--pink); opacity: 0.18; animation-delay: -20s; }
@keyframes glow-drift {
  0% { transform: translate(0, 0); }
  100% { transform: translate(60px, 40px); }
}

/* ============================================================
   导航
   ============================================================ */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  padding: 14px 0;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background .3s, border-color .3s, backdrop-filter .3s;
}
.nav.scrolled {
  background: rgba(10, 14, 39, 0.78);
  border-bottom-color: var(--line);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
}
.nav-inner {
  max-width: 1320px; margin: 0 auto; padding: 0 32px;
  display: flex; align-items: center; justify-content: space-between;
}
.nav-logo { display: flex; align-items: center; gap: 10px; }
.nav-logo img { width: 32px; height: 32px; }
.nav-logo-text { font-size: 19px; font-weight: 700; letter-spacing: -0.5px; color: #fff; }
.nav-badge {
  font-size: 11px; color: var(--cyan);
  padding: 2px 8px; border: 1px solid rgba(0,212,255,.3); border-radius: 4px;
  margin-left: 6px; letter-spacing: 0.3px;
}
.nav-links { display: flex; list-style: none; gap: 28px; align-items: center; }
.nav-links a { color: var(--text-dim); font-size: 14px; font-weight: 500; }
.nav-links a:hover { color: #fff; }
.nav-github { display: flex; align-items: center; gap: 6px; padding: 6px 12px; border: 1px solid var(--line); border-radius: 6px; }
.nav-github:hover { border-color: var(--cyan); }

/* ============================================================
   Hero
   ============================================================ */
.hero {
  position: relative; z-index: 1;
  min-height: 100vh;
  max-width: 1320px; margin: 0 auto;
  padding: 140px 32px 100px;
  display: grid; grid-template-columns: 1.05fr 1fr; gap: 60px; align-items: center;
  overflow: hidden;
}
.hero-canvas {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  opacity: 0.6;
  z-index: 0;
}
.hero-content { max-width: 660px; position: relative; z-index: 1; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 14px; border-radius: 999px;
  background: rgba(0, 212, 255, 0.08);
  border: 1px solid rgba(0, 212, 255, 0.3);
  font-size: 12px; color: var(--cyan); font-weight: 500;
  margin-bottom: 28px;
  animation: fadeInDown .8s ease-out;
}
.hero-badge .dot {
  width: 6px; height: 6px; border-radius: 50%; background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%,100% { opacity: 1; transform: scale(1); } 50% { opacity: 0.4; transform: scale(1.3); } }
@keyframes fadeInDown { from { opacity: 0; transform: translateY(-12px); } to { opacity: 1; transform: translateY(0); } }
.hero-title {
  font-size: 76px; line-height: 1.05; font-weight: 800;
  letter-spacing: -2.5px; color: #fff;
  margin-bottom: 24px;
  animation: fadeInUp .9s .1s both ease-out;
}
.grad-text {
  background: var(--grad);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
  display: inline-block;
  background-size: 200% auto;
  animation: grad-shift 6s ease-in-out infinite;
}
@keyframes grad-shift { 0%,100% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } }
.hero-subtitle {
  font-size: 18px; color: var(--text-dim); line-height: 1.7;
  margin-bottom: 40px;
  animation: fadeInUp .9s .2s both ease-out;
}
.hero-cta { display: flex; gap: 16px; margin-bottom: 64px; animation: fadeInUp .9s .3s both ease-out; }
@keyframes fadeInUp { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 26px; border-radius: 8px; font-size: 14px; font-weight: 600;
  cursor: pointer; transition: all .2s; border: 1px solid transparent;
  position: relative; overflow: hidden;
}
.btn-primary {
  background: var(--grad); color: #fff;
  box-shadow: 0 8px 30px rgba(0, 212, 255, 0.35);
}
.btn-primary::before {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.3) 0%, transparent 50%);
  opacity: 0; transition: opacity .3s;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 40px rgba(0, 212, 255, 0.5); color: #fff; }
.btn-primary:hover::before { opacity: 1; }
.btn-ghost { background: rgba(255,255,255,0.04); border-color: var(--line); color: var(--text); }
.btn-ghost:hover { background: rgba(255,255,255,0.08); border-color: var(--line-h); color: #fff; }
.hero-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; animation: fadeInUp .9s .4s both ease-out; }
.stat { border-left: 2px solid var(--line); padding-left: 16px; }
.stat-num { font-size: 24px; font-weight: 700; color: #fff; }
.stat-label { font-size: 12px; color: var(--text-mute); text-transform: uppercase; letter-spacing: 1px; margin-top: 4px; }

/* 终端 */
.hero-visual { position: relative; z-index: 1; }
.terminal {
  background: rgba(5, 7, 13, 0.78);
  border: 1px solid var(--line);
  border-radius: 14px;
  backdrop-filter: blur(10px);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(0, 212, 255, 0.1);
  overflow: hidden;
  transform: perspective(1400px) rotateY(-8deg) rotateX(3deg);
  transition: transform .5s cubic-bezier(.4,0,.2,1);
  animation: terminal-in 1s .5s both ease-out;
}
@keyframes terminal-in { from { opacity: 0; transform: perspective(1400px) rotateY(-15deg) rotateX(8deg) translateY(40px); } }
.terminal:hover { transform: perspective(1400px) rotateY(-3deg) rotateX(1deg); }
.terminal-bar {
  display: flex; align-items: center; gap: 6px;
  padding: 12px 16px;
  background: rgba(0, 0, 0, 0.3);
  border-bottom: 1px solid var(--line);
}
.terminal-bar .dot { width: 11px; height: 11px; border-radius: 50%; }
.dot.red { background: #ff5f57; }
.dot.yellow { background: #febc2e; }
.dot.green { background: #28c840; }
.terminal-title { margin-left: auto; font-size: 12px; color: var(--text-mute); font-family: "JetBrains Mono", monospace; }
.terminal-signal {
  margin-left: 16px; font-size: 11px; color: var(--green); font-family: "JetBrains Mono", monospace;
  display: flex; align-items: center; gap: 4px;
}
.signal-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--green); box-shadow: 0 0 6px var(--green); animation: pulse 1.5s infinite; }
.terminal-body { padding: 20px 24px; font-family: "JetBrains Mono", "SF Mono", monospace; font-size: 13px; line-height: 1.85; }
.t-line { padding: 2px 0; animation: line-in .4s both ease-out; }
@keyframes line-in { from { opacity: 0; transform: translateX(-6px); } }
.t-prompt { color: var(--cyan); font-weight: 600; }
.cursor { display: inline-block; animation: blink 1s step-end infinite; color: var(--cyan); }
@keyframes blink { 50% { opacity: 0; } }
.t-think { color: var(--text-mute); font-size: 12px; }
.t-tool { color: var(--yellow); font-size: 12px; }
.t-tag { display: inline-block; padding: 1px 6px; border-radius: 3px; background: rgba(255, 200, 87, 0.15); color: var(--yellow); margin-right: 4px; font-size: 10px; font-weight: 700; }
.t-result { color: var(--green); font-size: 12px; }
.t-md-block {
  margin-top: 10px; padding: 10px 12px;
  background: rgba(0, 212, 255, 0.04); border-left: 2px solid var(--cyan); border-radius: 0 6px 6px 0;
  animation: line-in .4s .8s both ease-out;
}
.t-md-title { font-family: -apple-system, sans-serif; font-weight: 700; color: #fff; font-size: 13px; margin-bottom: 4px; }
.t-md-body { font-family: -apple-system, sans-serif; font-size: 13px; color: var(--text); line-height: 1.6; }
.t-up { color: var(--green); font-weight: 700; }
.t-down { color: var(--pink); font-weight: 700; }
.t-chart { margin-top: 10px; height: 90px; display: flex; align-items: flex-end; gap: 6px; padding: 0 4px; animation: line-in .4s 1s both ease-out; }
.t-chart .bar {
  flex: 1; height: 0; background: var(--grad); border-radius: 3px 3px 0 0;
  position: relative; min-width: 20px;
  animation: bar-grow 1s 1s ease-out forwards;
  transition: transform .2s;
}
.t-chart .bar:hover { transform: scaleY(1.1); transform-origin: bottom; }
.t-chart .bar span { position: absolute; bottom: -18px; left: 50%; transform: translateX(-50%); font-size: 9px; color: var(--text-mute); font-family: -apple-system, sans-serif; white-space: nowrap; }
@keyframes bar-grow { from { height: 0; } to { height: var(--h, 50%); } }
.t-line.t-cite { color: var(--text-mute); font-size: 11px; padding-top: 8px; border-top: 1px dashed var(--line); margin-top: 20px; animation: line-in .4s 1.2s both ease-out; }

/* ============================================================
   Section 通用
   ============================================================ */
.section { position: relative; z-index: 1; padding: 110px 32px; max-width: 1320px; margin: 0 auto; }
.section-alt { background: linear-gradient(180deg, transparent 0%, rgba(10, 14, 39, 0.4) 50%, transparent 100%); }
.section-head { text-align: center; margin-bottom: 64px; }
.section-eyebrow {
  display: inline-block; padding: 4px 12px; border-radius: 4px;
  background: rgba(0, 212, 255, 0.08); border: 1px solid rgba(0, 212, 255, 0.2);
  font-size: 12px; color: var(--cyan); font-weight: 600; letter-spacing: 1.5px;
  margin-bottom: 16px;
}
.section-title { font-size: 44px; font-weight: 700; color: #fff; letter-spacing: -1px; margin-bottom: 14px; }
.section-desc { font-size: 17px; color: var(--text-dim); max-width: 700px; margin: 0 auto; }
.section-desc strong { color: #fff; }

/* ============================================================
   Features Grid
   ============================================================ */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card {
  background: linear-gradient(180deg, rgba(19, 24, 56, 0.6) 0%, rgba(10, 14, 39, 0.4) 100%);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 32px 28px;
  position: relative; overflow: hidden;
  opacity: 0; transform: translateY(24px);
  transition: transform .4s cubic-bezier(.4,0,.2,1), border-color .3s, box-shadow .3s;
}
.feature-card.in { opacity: 1; transform: translateY(0); }
.feature-card::after {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(circle at var(--mx, 50%) var(--my, 50%), rgba(0,212,255,0.15) 0%, transparent 40%);
  opacity: 0; transition: opacity .3s; pointer-events: none;
}
.feature-card:hover { transform: translateY(-6px); border-color: var(--line-h); box-shadow: 0 20px 50px rgba(0,0,0,.3); }
.feature-card:hover::after { opacity: 1; }
.feature-icon {
  width: 50px; height: 50px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 20px;
  transition: transform .4s;
}
.feature-card:hover .feature-icon { transform: scale(1.1) rotate(-3deg); }
.icon-purple { background: rgba(124, 77, 255, 0.15); color: #b39aff; }
.icon-cyan   { background: rgba(0, 212, 255, 0.15); color: #66e8ff; }
.icon-green  { background: rgba(0, 212, 154, 0.15); color: #4ddcb1; }
.icon-pink   { background: rgba(255, 94, 157, 0.15); color: #ff9bc4; }
.icon-yellow { background: rgba(255, 200, 87, 0.15); color: #ffd57a; }
.icon-blue   { background: rgba(80, 130, 255, 0.15); color: #97b3ff; }
.feature-card h3 { font-size: 18px; font-weight: 600; color: #fff; margin-bottom: 10px; }
.feature-card p { font-size: 14px; color: var(--text-dim); line-height: 1.7; }

/* ============================================================
   Scenarios
   ============================================================ */
.scenario-tabs {
  display: flex; justify-content: center; gap: 12px;
  margin-bottom: 48px; flex-wrap: wrap;
}
.scenario-tabs .tab {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 22px; border-radius: 999px;
  background: rgba(19, 24, 56, 0.4); border: 1px solid var(--line);
  color: var(--text-dim); font-size: 14px; font-weight: 500;
  cursor: pointer; transition: all .3s;
}
.scenario-tabs .tab:hover { color: #fff; border-color: var(--line-h); transform: translateY(-2px); }
.scenario-tabs .tab.active {
  background: var(--grad); color: #fff;
  border-color: transparent;
  box-shadow: 0 8px 24px rgba(0, 212, 255, 0.4);
}
.scenario-panel {
  display: none;
  grid-template-columns: 1fr 1.2fr; gap: 48px;
  background: linear-gradient(180deg, rgba(19, 24, 56, 0.6) 0%, rgba(10, 14, 39, 0.3) 100%);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 48px;
  opacity: 0;
}
.scenario-panel.active { display: grid; animation: panel-in .5s ease-out forwards; }
@keyframes panel-in { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
.scenario-tag {
  display: inline-block; padding: 4px 10px; border-radius: 4px;
  background: rgba(0, 212, 255, 0.1); color: var(--cyan);
  font-size: 11px; font-weight: 700; letter-spacing: 1.5px;
  margin-bottom: 16px;
}
.scenario-panel h3 { font-size: 36px; color: #fff; margin-bottom: 14px; letter-spacing: -0.5px; }
.scenario-desc { font-size: 15px; color: var(--text-dim); line-height: 1.7; margin-bottom: 28px; }
.scenario-points { list-style: none; margin-bottom: 28px; }
.scenario-points li {
  font-size: 14px; color: var(--text); padding: 8px 0;
  display: flex; align-items: center; gap: 10px;
}
.check {
  width: 18px; height: 18px; border-radius: 50%;
  background: rgba(0, 212, 154, 0.15); position: relative; flex-shrink: 0;
}
.check::after {
  content: ''; position: absolute; left: 5px; top: 3px;
  width: 6px; height: 10px; border: solid var(--green);
  border-width: 0 2px 2px 0; transform: rotate(45deg);
}
.scenario-quote {
  background: rgba(0, 0, 0, 0.3); border-left: 3px solid var(--purple);
  padding: 16px 20px; border-radius: 0 8px 8px 0;
}
.scenario-quote p { font-size: 14px; color: var(--text); font-style: italic; margin-bottom: 8px; }
.scenario-quote-by { font-size: 12px; color: var(--text-mute); }
.scenario-right { display: flex; align-items: center; }
.scenario-demo {
  background: rgba(5, 7, 13, 0.5);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 28px;
  width: 100%;
  box-shadow: 0 12px 40px rgba(0,0,0,0.3);
}
.demo-query {
  font-family: "JetBrains Mono", monospace; font-size: 13px;
  color: var(--cyan); padding-bottom: 16px;
  border-bottom: 1px solid var(--line); margin-bottom: 18px;
}
.demo-metrics {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px;
  margin-bottom: 24px;
}
.demo-metric {
  background: rgba(19, 24, 56, 0.6); border: 1px solid var(--line);
  border-radius: 10px; padding: 14px; text-align: center;
  transition: transform .3s;
}
.demo-metric:hover { transform: translateY(-3px); border-color: var(--line-h); }
.demo-metric-num { font-size: 22px; font-weight: 700; color: #fff; margin-bottom: 4px; }
.demo-metric-label { font-size: 11px; color: var(--text-mute); }
.demo-chart { background: rgba(19, 24, 56, 0.4); border-radius: 8px; padding: 16px; }
.demo-svg { width: 100%; height: 140px; }
.demo-dots circle { animation: dot-pulse 2s ease-in-out infinite; }
.demo-dots circle:nth-child(2) { animation-delay: .2s; }
.demo-dots circle:nth-child(3) { animation-delay: .4s; }
.demo-dots circle:nth-child(4) { animation-delay: .6s; }
.demo-dots circle:nth-child(5) { animation-delay: .8s; }
.demo-dots circle:nth-child(6) { animation-delay: 1s; }
.demo-dots circle:nth-child(7) { animation-delay: 1.2s; }
@keyframes dot-pulse { 0%,100% { r: 3; opacity: 1; } 50% { r: 5; opacity: 0.7; } }
.demo-chart-labels { display: flex; justify-content: space-between; padding: 8px 0 0; font-size: 10px; color: var(--text-mute); }
.demo-bar-chart { display: flex; align-items: flex-end; gap: 8px; height: 140px; padding: 0 8px; }
.dbar {
  flex: 1; height: 0; background: var(--grad); border-radius: 6px 6px 0 0;
  position: relative; min-width: 30px;
  display: flex; flex-direction: column; justify-content: flex-end;
  animation: bar-grow 1s ease-out forwards;
  transition: transform .3s;
}
.dbar:hover { transform: scaleY(1.08); transform-origin: bottom; }
.dbar span { position: absolute; bottom: -22px; left: 0; right: 0; text-align: center; font-size: 11px; color: var(--text-dim); }
.dbar em { position: absolute; top: -22px; left: 0; right: 0; text-align: center; font-size: 11px; color: var(--cyan); font-style: normal; font-weight: 600; }
@keyframes bar-grow { from { height: 0; } to { height: calc(var(--v, 50) * 1%); } }
.demo-donut { display: flex; align-items: center; justify-content: center; gap: 24px; padding: 8px 0; }
.demo-donut svg { width: 120px; height: 120px; animation: donut-draw 1.5s ease-out forwards; }
.donut-label { font-size: 14px; color: var(--text-dim); line-height: 1.6; }
.donut-label span { color: var(--cyan); font-weight: 600; }
@keyframes donut-draw { from { stroke-dasharray: 0 314; } }
.demo-trace { display: flex; flex-direction: column; gap: 0; }
.trace-node {
  background: rgba(19, 24, 56, 0.5); border: 1px solid var(--line);
  border-radius: 10px; padding: 14px 16px;
  display: flex; align-items: center; gap: 14px;
}
.trace-tag {
  font-size: 12px; font-weight: 700; padding: 4px 10px;
  border-radius: 4px; letter-spacing: 1px;
}
.tag-cyan { background: rgba(0,212,255,0.15); color: var(--cyan); }
.tag-purple { background: rgba(124,77,255,0.15); color: #b39aff; }
.tag-green { background: rgba(0,212,154,0.15); color: var(--green); }
.trace-info { font-size: 13px; color: var(--text); flex: 1; }
.trace-info span { display: block; font-size: 11px; color: var(--text-mute); margin-top: 2px; }
.trace-arrow { text-align: center; color: var(--cyan); font-size: 18px; padding: 4px 0; animation: arrow-down 1.5s ease-in-out infinite; }
@keyframes arrow-down { 0%,100% { transform: translateY(0); } 50% { transform: translateY(4px); } }

/* ============================================================
   Architecture
   ============================================================ */
.arch-flow { max-width: 1080px; margin: 0 auto; }
.arch-layer {
  background: rgba(19, 24, 56, 0.4); border: 1px solid var(--line);
  border-radius: 16px; padding: 32px;
  position: relative;
}
.arch-layer-tag {
  position: absolute; top: -10px; left: 32px; padding: 3px 12px;
  background: var(--bg-1); border: 1px solid var(--cyan); border-radius: 4px;
  font-size: 11px; font-weight: 700; color: var(--cyan); letter-spacing: 1.5px;
}
.tag-purple { border-color: var(--purple); color: var(--purple); }
.tag-cyan { border-color: var(--cyan); color: var(--cyan); }
.arch-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.arch-card-mini {
  background: rgba(5, 7, 13, 0.5); border: 1px solid var(--line);
  border-radius: 10px; padding: 18px;
  transition: transform .3s, border-color .3s;
  opacity: 0; transform: translateY(12px);
}
.arch-card-mini.in { opacity: 1; transform: translateY(0); transition: all .5s cubic-bezier(.4,0,.2,1); }
.arch-card-mini:hover { transform: translateY(-3px); border-color: var(--line-h); }
.mini-icon { width: 38px; height: 38px; border-radius: 8px; display: flex; align-items: center; justify-content: center; margin-bottom: 12px; }
.arch-card-mini h4 { font-size: 15px; color: #fff; margin-bottom: 4px; }
.arch-card-mini p { font-size: 12px; color: var(--text-mute); }
.arch-arrow { text-align: center; color: var(--cyan); font-size: 24px; padding: 12px 0; }
.arch-defense { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
.defense-card {
  background: rgba(5, 7, 13, 0.5); border: 1px solid var(--line);
  border-radius: 10px; padding: 20px 16px; text-align: center;
  position: relative; overflow: hidden;
  opacity: 0; transform: translateY(12px);
}
.defense-card.in { opacity: 1; transform: translateY(0); transition: all .5s .1s cubic-bezier(.4,0,.2,1); }
.defense-card:hover { border-color: var(--purple); }
.defense-num {
  font-size: 28px; font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent;
  margin-bottom: 8px;
}
.defense-card h4 { font-size: 14px; color: #fff; margin-bottom: 6px; }
.defense-card p { font-size: 11px; color: var(--text-mute); line-height: 1.5; }

/* ============================================================
   Versions
   ============================================================ */
.version-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.version-card {
  background: rgba(19, 24, 56, 0.4); border: 1px solid var(--line);
  border-radius: 16px; padding: 28px;
  position: relative;
  opacity: 0; transform: translateY(20px);
  transition: transform .4s, border-color .3s, box-shadow .3s;
}
.version-card.in { opacity: 1; transform: translateY(0); }
.version-card:hover { transform: translateY(-6px); border-color: var(--line-h); box-shadow: 0 16px 40px rgba(0,0,0,.3); }
.version-popular {
  background: linear-gradient(180deg, rgba(0, 212, 255, 0.08) 0%, rgba(124, 77, 255, 0.06) 100%);
  border-color: var(--cyan);
  box-shadow: 0 0 30px rgba(0, 212, 255, 0.2);
  transform: translateY(-8px);
}
.version-popular.in { transform: translateY(-8px); }
.version-popular:hover { transform: translateY(-14px); }
.version-popular-badge {
  position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
  background: var(--grad); color: #fff;
  padding: 4px 16px; border-radius: 999px;
  font-size: 11px; font-weight: 700; letter-spacing: 1px;
  box-shadow: 0 4px 16px rgba(0, 212, 255, 0.4);
}
.version-name { font-size: 22px; font-weight: 700; color: #fff; margin-bottom: 4px; }
.version-tag {
  font-size: 11px; color: var(--cyan); font-weight: 600;
  letter-spacing: 1.5px; margin-bottom: 18px;
}
.version-popular .version-tag { color: var(--green); }
.version-price { display: flex; align-items: baseline; gap: 4px; margin-bottom: 8px; }
.price-num { font-size: 32px; font-weight: 800; color: #fff; }
.price-unit { font-size: 14px; color: var(--text-mute); }
.version-desc { font-size: 12px; color: var(--text-dim); padding-bottom: 16px; border-bottom: 1px solid var(--line); margin-bottom: 16px; }
.version-feats { list-style: none; margin-bottom: 24px; min-height: 160px; }
.version-feats li {
  font-size: 13px; padding: 7px 0; display: flex; align-items: center; gap: 8px;
  color: var(--text-mute);
}
.feat-on { color: var(--text); }
.feat-on::before { content: '✓'; color: var(--green); font-weight: 700; }
.feat-off::before { content: '×'; color: var(--text-mute); }
.version-btn {
  display: block; text-align: center; padding: 10px 16px;
  border-radius: 8px; font-size: 13px; font-weight: 600;
  background: rgba(255,255,255,0.05); border: 1px solid var(--line); color: var(--text);
  transition: all .2s;
}
.version-btn:hover { background: rgba(255,255,255,0.1); color: #fff; }
.version-btn-primary {
  background: var(--grad); color: #fff; border-color: transparent;
  box-shadow: 0 4px 16px rgba(0, 212, 255, 0.35);
}
.version-btn-primary:hover { transform: translateY(-2px); color: #fff; }

/* ============================================================
   Stack Grid
   ============================================================ */
.stack-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.stack-group {
  background: rgba(19, 24, 56, 0.4);
  border: 1px solid var(--line);
  border-radius: 16px; padding: 28px;
  opacity: 0; transform: translateY(20px);
}
.stack-group.in { opacity: 1; transform: translateY(0); transition: all .6s .2s cubic-bezier(.4,0,.2,1); }
.stack-group h4 {
  font-size: 16px; font-weight: 700; color: #fff; margin-bottom: 18px;
  padding-bottom: 10px; border-bottom: 1px solid var(--line);
}
.stack-group ul { list-style: none; }
.stack-group li {
  font-size: 14px; color: var(--text-dim);
  padding: 7px 0; display: flex; align-items: center; gap: 10px;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  transition: color .2s;
}
.stack-group li:hover { color: #fff; }
.stack-group li:last-child { border-bottom: none; }
.dot-c { width: 6px; height: 6px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 8px var(--cyan); }
.dot-v { width: 6px; height: 6px; border-radius: 50%; background: var(--green); box-shadow: 0 0 8px var(--green); }
.dot-d { width: 6px; height: 6px; border-radius: 50%; background: var(--purple); box-shadow: 0 0 8px var(--purple); }

/* ============================================================
   Contact
   ============================================================ */
.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.contact-card {
  background: rgba(19, 24, 56, 0.4); border: 1px solid var(--line);
  border-radius: 16px; padding: 32px;
  text-align: center;
  transition: transform .3s, border-color .3s, box-shadow .3s;
  opacity: 0; transform: translateY(20px);
}
.contact-card.in { opacity: 1; transform: translateY(0); transition: all .5s .3s cubic-bezier(.4,0,.2,1); }
.contact-card:hover { transform: translateY(-4px); border-color: var(--line-h); box-shadow: 0 16px 40px rgba(0,0,0,.3); }
.contact-icon {
  width: 50px; height: 50px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 18px;
}
.contact-card h4 { font-size: 16px; color: #fff; margin-bottom: 6px; }
.contact-card p { font-size: 12px; color: var(--text-mute); margin-bottom: 14px; }
.contact-card a { font-size: 14px; color: var(--cyan); font-family: "JetBrains Mono", monospace; }

/* ============================================================
   Footer
   ============================================================ */
.footer {
  position: relative; z-index: 1;
  border-top: 1px solid var(--line);
  padding: 48px 32px;
  margin-top: 80px;
  background: rgba(5, 7, 13, 0.5);
}
.footer-inner {
  max-width: 1320px; margin: 0 auto;
  display: flex; justify-content: space-between; align-items: center; gap: 24px;
  flex-wrap: wrap;
}
.footer-left { display: flex; align-items: center; gap: 16px; }
.footer-logo { width: 36px; height: 36px; }
.footer-title { font-size: 14px; font-weight: 600; color: #fff; }
.footer-sub { font-size: 12px; color: var(--text-mute); margin-top: 2px; }
.footer-right { display: flex; gap: 20px; align-items: center; font-size: 13px; flex-wrap: wrap; }
.footer-right a { color: var(--text-dim); }
.footer-right a:hover { color: #fff; }
.footer-meta { color: var(--text-mute); font-family: "JetBrains Mono", monospace; font-size: 12px; }

/* ============================================================
   返回顶部按钮
   ============================================================ */
.back-top {
  position: fixed; bottom: 32px; right: 32px; z-index: 90;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--bg-1); border: 1px solid var(--line);
  color: var(--cyan); cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; transform: translateY(20px);
  transition: all .3s;
  box-shadow: 0 8px 24px rgba(0,0,0,.4);
}
.back-top.visible { opacity: 1; transform: translateY(0); }
.back-top:hover { background: var(--cyan); color: #fff; transform: translateY(-3px); box-shadow: 0 12px 30px rgba(0,212,255,.5); }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1100px) {
  .hero { grid-template-columns: 1fr; padding-top: 120px; }
  .hero-visual { margin-top: 40px; }
  .terminal { transform: none; }
  .feature-grid, .stack-grid, .qs-grid, .contact-grid, .version-grid { grid-template-columns: 1fr 1fr; }
  .arch-cards, .arch-defense { grid-template-columns: 1fr 1fr; }
  .scenario-panel { grid-template-columns: 1fr; padding: 32px; }
  .nav-links { display: none; }
  .nav-badge { display: none; }
}
@media (max-width: 720px) {
  .hero-title { font-size: 48px; }
  .section-title { font-size: 30px; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .feature-grid, .stack-grid, .qs-grid, .contact-grid, .version-grid { grid-template-columns: 1fr; }
  .arch-cards, .arch-defense { grid-template-columns: 1fr; }
  .demo-metrics { grid-template-columns: repeat(2, 1fr); }
  .section { padding: 80px 20px; }
  .scenario-tabs .tab { padding: 10px 16px; font-size: 13px; }
}

/* ============================================================
   无障碍
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* 鼠标位置跟踪 (feature-card 渐变光斑) */
.feature-card { --mx: 50%; --my: 50%; }