/* ============================================
   ClawStart Design System v3.0
   Based on: frontend-design-system skill
   Refs: skillhub.tencent.com + impeccable.style
   ============================================ */

/* --- 1. Design Tokens --- */
:root {
  /* Brand — Lobster Red 🦞 #E85A4F */
  --brand-50:  #FEF2F1;
  --brand-100: #FDE0DE;
  --brand-400: #EF7B72;
  --brand-500: #E85A4F;
  --brand-600: #D04840;
  --brand-700: #B03A33;

  /* Accent Blue (secondary) */
  --accent-400: #60A5FA;
  --accent-500: #3B82F6;
  --accent-600: #2563EB;

  /* Neutral */
  --gray-50:  #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-800: #1F2937;
  --gray-900: #0F172A;

  /* Dark surfaces */
  --dark-bg:    #0B1120;
  --dark-bg-2:  #1E293B;
  --dark-text:  #F1F5F9;
  --dark-muted: #94A3B8;

  /* Semantic */
  --success: #10B981;
  --warning: #F59E0B;
  --danger:  #EF4444;
  --info:    #3B82F6;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC",
               sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", "SF Mono", monospace;

  /* Spacing (4px base) */
  --space-1:  4px;
  --space-2:  8px;
  --space-3:  12px;
  --space-4:  16px;
  --space-5:  20px;
  --space-6:  24px;
  --space-8:  32px;
  --space-10: 40px;
  --space-12: 48px;
  --space-16: 64px;
  --space-20: 80px;

  /* Radius */
  --radius-sm:   6px;
  --radius-md:   8px;
  --radius-lg:   12px;
  --radius-xl:   16px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,.12);
  --shadow-xl: 0 16px 48px rgba(0,0,0,.16);

  /* Motion */
  --ease-out:    cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --dur-fast:    150ms;
  --dur-normal:  250ms;
  --dur-slow:    400ms;

  /* Layout */
  --max-width:   1200px;
  --content-width: 720px;

  /* === Theme tokens (light default) === */
  --theme-bg:        #ffffff;
  --theme-bg-alt:    var(--gray-50);
  --theme-bg-card:   #ffffff;
  --theme-text:      var(--gray-900);
  --theme-text-secondary: var(--gray-500);
  --theme-text-muted: var(--gray-400);
  --theme-border:    var(--gray-200);
  --theme-nav-bg:    rgba(255,255,255,0.85);
  --theme-nav-text:  var(--gray-600);
  --theme-hero-bg:   var(--dark-bg);
  --theme-hero-text: var(--dark-text);
  --theme-hero-muted: var(--dark-muted);
  --theme-hero-fade-end: var(--gray-50);
  --theme-code-bg:   var(--gray-50);
  --theme-code-text: var(--gray-800);
  --theme-footer-bg: var(--gray-900);
  --theme-footer-text: var(--gray-400);
  --theme-shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --theme-shadow-md: 0 4px 12px rgba(0,0,0,.08);
  --theme-shadow-lg: 0 8px 30px rgba(0,0,0,.12);
}

/* === Dark theme overrides === */
[data-theme="dark"] {
  /* Unified deep dark background — matches hero, inspired by QClaw */
  --theme-bg:        #060A14;
  --theme-bg-alt:    #060A14;
  --theme-bg-card:   rgba(255,255,255,0.04);
  --theme-text:      #F1F5F9;
  --theme-text-secondary: #94A3B8;
  --theme-text-muted: #64748B;
  --theme-border:    rgba(255,255,255,0.08);
  --theme-nav-bg:    rgba(6,10,20,0.92);
  --theme-nav-text:  #94A3B8;
  --theme-hero-bg:   #060A14;
  --theme-hero-text: #F1F5F9;
  --theme-hero-muted: #94A3B8;
  --theme-hero-fade-end: #060A14;
  --theme-code-bg:   rgba(255,255,255,0.06);
  --theme-code-text: #E2E8F0;
  --theme-footer-bg: #060A14;
  --theme-footer-text: #64748B;
  --theme-shadow-sm: 0 1px 2px rgba(0,0,0,.3);
  --theme-shadow-md: 0 4px 12px rgba(0,0,0,.4);
  --theme-shadow-lg: 0 8px 30px rgba(0,0,0,.5);
}

/* --- 2. Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--theme-text);
  background: var(--theme-bg);
  line-height: 1.6;
  transition: background var(--dur-normal) var(--ease-out), color var(--dur-normal) var(--ease-out);
}

a { color: var(--brand-500); text-decoration: none; transition: color var(--dur-fast) var(--ease-out); }
a:hover { color: var(--brand-600); }

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

/* Focus ring for accessibility */
:focus-visible {
  outline: 2px solid var(--brand-500);
  outline-offset: 2px;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
}

/* --- 3. Layout --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.section {
  padding: var(--space-20) 0;
}

.section-alt {
  background: var(--theme-bg-alt);
}

.section-white {
  background: var(--theme-bg);
}

/* Stripe rhythm: alternate white/gray sections */
.section + .section-alt,
.section-alt + .section {
  /* no border needed, background color change creates rhythm */
}

/* --- 4. Typography --- */
h1, h2, h3, h4, h5, h6 {
  color: var(--theme-text);
  line-height: 1.3;
}

.text-hero {
  font-size: 48px;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.text-h1 { font-size: 36px; font-weight: 800; line-height: 1.2; }
.text-h2 { font-size: 24px; font-weight: 700; line-height: 1.3; }
.text-h3 { font-size: 18px; font-weight: 600; line-height: 1.4; }
.text-body { font-size: 15px; line-height: 1.7; color: var(--theme-text-secondary); }
.text-sm { font-size: 13px; line-height: 1.5; color: var(--theme-text-muted); }

.section-title {
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--brand-400);
  margin-bottom: var(--space-3);
}

/* --- 5. Header / Nav --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: transparent;
  backdrop-filter: blur(0px);
  -webkit-backdrop-filter: blur(0px);
  border-bottom: 1px solid transparent;
  transition: all var(--dur-normal) var(--ease-out);
}

.site-header.scrolled {
  background: var(--theme-nav-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom-color: var(--theme-border);
  box-shadow: var(--theme-shadow-sm);
}

/* Nav brand/links on dark hero before scroll */
.nav-brand {
  font-size: 18px;
  font-weight: 700;
  color: var(--dark-text) !important;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  transition: color var(--dur-normal) var(--ease-out);
}

.scrolled .nav-brand {
  color: var(--theme-text) !important;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: rgba(241,245,249,.7);
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--dur-fast) var(--ease-out);
}

.scrolled .nav-links a {
  color: var(--theme-nav-text);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--dark-text);
}

.scrolled .nav-links a:hover,
.scrolled .nav-links a.active {
  color: var(--theme-text);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* Theme toggle button */
.theme-toggle {
  background: none;
  border: 1px solid transparent;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--dark-text);
  font-size: 20px;
  transition: all var(--dur-fast) var(--ease-out);
}

.theme-toggle:hover {
  background: rgba(255,255,255,.1);
  border-color: rgba(255,255,255,.2);
}

.scrolled .theme-toggle {
  color: var(--theme-text);
}

.scrolled .theme-toggle:hover {
  background: var(--theme-bg-alt);
  border-color: var(--theme-border);
}

.nav-links {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: var(--space-8);
  align-items: center;
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--brand-400);
  border-radius: 1px;
}

/* Dropdown */
.nav-dropdown {
  position: relative;
}

.nav-dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  min-width: 160px;
  padding: var(--space-2) 0;
  margin: 0;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(12px);
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  list-style: none;
  z-index: 100;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.15s ease, visibility 0.15s ease, transform 0.15s ease;
}

.nav-dropdown:hover > .nav-dropdown-menu,
.nav-dropdown:focus-within > .nav-dropdown-menu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.nav-dropdown-menu li a {
  display: block;
  padding: var(--space-2) var(--space-4);
  font-size: 13px;
  color: var(--gray-600);
  white-space: nowrap;
  transition: background var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}

.nav-dropdown-menu li a:hover {
  background: var(--gray-50);
  color: var(--brand-500);
}

.nav-dropdown-menu li a.active {
  color: var(--brand-500);
  font-weight: 600;
}

/* Dropdown item active — no underline like top-level */
.nav-dropdown-menu li a.active::after {
  display: none;
}

/* Scrolled / dark theme dropdown */
.scrolled .nav-dropdown-menu,
[data-theme="dark"] .nav-dropdown-menu {
  background: var(--theme-bg-card);
  border-color: var(--theme-border);
}

.scrolled .nav-dropdown-menu li a,
[data-theme="dark"] .nav-dropdown-menu li a {
  color: var(--theme-text-secondary);
}

.scrolled .nav-dropdown-menu li a:hover,
[data-theme="dark"] .nav-dropdown-menu li a:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--brand-400);
}

.scrolled .nav-dropdown-menu li a.active,
[data-theme="dark"] .nav-dropdown-menu li a.active {
  color: var(--brand-400);
}

/* Dropdown parent arrow indicator */
.nav-dropdown > a::after {
  content: "";
  display: inline-block;
  width: 4px;
  height: 4px;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg);
  margin-left: 4px;
  vertical-align: middle;
  position: relative;
  top: -1px;
  transition: transform var(--dur-fast) var(--ease-out);
}

.nav-dropdown:hover > a::after {
  transform: rotate(-135deg);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--theme-text);
  padding: var(--space-2);
  min-width: 44px;
  min-height: 44px;
}

/* --- 6. Hero --- */
.hero {
  background: var(--theme-hero-bg);
  padding: calc(64px + var(--space-20)) 0 var(--space-20);
  text-align: center;
  position: relative;
  overflow: hidden;
  min-height: 100vh;
  display: flex;
  align-items: center;
}

/* Subtle grid pattern overlay */
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 30%, transparent 70%);
  pointer-events: none;
}

/* Floating orbs for depth */
.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  will-change: transform;
}

.hero-orb-1 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(232,90,79,.18) 0%, transparent 70%);
  top: -10%;
  left: -10%;
  animation: orbFloat1 12s ease-in-out infinite;
}

.hero-orb-2 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(255,139,76,.12) 0%, transparent 70%);
  top: 10%;
  right: -8%;
  animation: orbFloat2 15s ease-in-out infinite;
}

.hero-orb-3 {
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(59,130,246,.10) 0%, transparent 70%);
  bottom: 5%;
  left: 30%;
  animation: orbFloat3 18s ease-in-out infinite;
}

@keyframes orbFloat1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, 30px) scale(1.05); }
  66% { transform: translate(-20px, -15px) scale(0.95); }
}

@keyframes orbFloat2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(-30px, 40px) scale(0.95); }
  66% { transform: translate(20px, -30px) scale(1.08); }
}

@keyframes orbFloat3 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-40px, -20px) scale(1.1); }
}

/* Bottom fade — smooth hero-to-content transition */
.hero::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 200px;
  background: linear-gradient(180deg, transparent 0%, var(--theme-hero-fade-end) 100%);
  pointer-events: none;
}

/* Hero content */
.hero-content {
  position: relative;
  z-index: 2;
}

/* Badge */
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,255,255,.06);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,.1);
  border-radius: var(--radius-full);
  padding: 6px 18px 6px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--dark-muted);
  margin-bottom: var(--space-8);
  animation: fadeInUp 0.8s var(--ease-out) both;
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  background: var(--brand-400);
  border-radius: 50%;
  display: inline-block;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(239,123,114,.4); }
  50% { opacity: .8; box-shadow: 0 0 0 6px rgba(239,123,114,0); }
}

/* Hero title */
.hero-title {
  font-size: 56px;
  font-weight: 800;
  color: var(--dark-text);
  line-height: 1.12;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-5);
  animation: fadeInUp 0.8s var(--ease-out) 0.1s both;
}

.text-gradient {
  background: linear-gradient(135deg, #FF6B6B 0%, #FF8A5C 30%, #FFB347 60%, #FF6B6B 100%);
  background-size: 200% 200%;
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: gradientShift 6s ease-in-out infinite;
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* Hero description */
.hero-desc {
  color: var(--dark-muted);
  font-size: 18px;
  line-height: 1.7;
  max-width: 520px;
  margin: 0 auto var(--space-10);
  animation: fadeInUp 0.8s var(--ease-out) 0.2s both;
}

/* Hero actions */
.hero-actions {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-12);
  animation: fadeInUp 0.8s var(--ease-out) 0.3s both;
}

/* Glow button */
.btn-glow {
  position: relative;
  overflow: visible;
}

.btn-glow::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  background: linear-gradient(135deg, #E85A4F, #FF8A5C);
  opacity: 0;
  filter: blur(12px);
  transition: opacity var(--dur-normal) var(--ease-out);
  z-index: -1;
}

.btn-glow:hover::before {
  opacity: 0.5;
}

/* Terminal mockup */
.hero-terminal {
  max-width: 540px;
  margin: 0 auto var(--space-10);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: rgba(15,23,42,.8);
  border: 1px solid rgba(255,255,255,.08);
  box-shadow:
    0 0 0 1px rgba(255,255,255,.05),
    0 20px 50px -12px rgba(0,0,0,.5),
    0 0 80px -20px rgba(37,99,235,.15);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  text-align: left;
  animation: fadeInUp 0.8s var(--ease-out) 0.5s both;
}

.terminal-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: rgba(255,255,255,.04);
  border-bottom: 1px solid rgba(255,255,255,.06);
}

.terminal-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  display: inline-block;
}

.terminal-title {
  flex: 1;
  text-align: center;
  font-size: 12px;
  color: rgba(148,163,184,.5);
  font-weight: 500;
  margin-right: 36px; /* compensate for dots */
}

.terminal-body {
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.8;
}

.terminal-line {
  display: flex;
  align-items: center;
  gap: 8px;
}

.terminal-prompt {
  color: var(--success);
  font-weight: 700;
  flex-shrink: 0;
}

.terminal-cmd {
  color: #E2E8F0;
}

.terminal-cursor {
  display: inline-block;
  width: 8px;
  height: 18px;
  background: var(--brand-400);
  border-radius: 1px;
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.terminal-output {
  color: var(--dark-muted);
  font-size: 13px;
}

.terminal-success {
  color: var(--success);
}

/* Trust badges */
.hero-trust {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-5);
  flex-wrap: wrap;
  animation: fadeInUp 0.8s var(--ease-out) 0.6s both;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 500;
  color: var(--dark-muted);
}

.trust-icon {
  font-size: 16px;
}

.trust-divider {
  width: 1px;
  height: 16px;
  background: rgba(148,163,184,.2);
}

/* Entrance animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Page-level hero (smaller) */
.page-hero {
  background: linear-gradient(180deg, var(--dark-bg), var(--dark-bg-2));
  padding: calc(64px + var(--space-16)) 0 var(--space-16);
  text-align: center;
  position: relative;
}

.page-hero::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 120px;
  background: linear-gradient(
    180deg,
    transparent 0%,
    rgba(30, 41, 59, 0.4) 30%,
    rgba(249, 250, 251, 0.3) 60%,
    rgba(249, 250, 251, 0.8) 85%,
    var(--gray-50) 100%
  );
  pointer-events: none;
}

.page-hero h1 {
  font-size: 36px;
  font-weight: 800;
  color: var(--dark-text);
  margin-bottom: var(--space-2);
}

.page-hero p {
  color: var(--dark-muted);
  font-size: 18px;
}

/* --- 7. Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px 28px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 15px;
  font-family: inherit;
  cursor: pointer;
  border: none;
  transition: all var(--dur-fast) var(--ease-out);
  min-height: 44px;
  text-decoration: none;
}

.btn-primary {
  background: var(--brand-500);
  color: #fff;
  box-shadow: 0 1px 2px rgba(232, 90, 79, 0.2);
}

.btn-primary:hover {
  background: var(--brand-600);
  color: #fff;
  box-shadow: 0 4px 12px rgba(232, 90, 79, 0.3);
  transform: translateY(-1px);
}

.btn-outline-dark {
  background: transparent;
  color: var(--gray-800);
  border: 1.5px solid var(--gray-200);
}

.btn-outline-dark:hover {
  border-color: var(--gray-300);
  background: var(--gray-50);
  color: var(--gray-900);
}

/* Ghost button for dark backgrounds */
.btn-outline {
  background: transparent;
  color: var(--dark-muted);
  border: 1.5px solid rgba(148, 163, 184, 0.4);
}

.btn-outline:hover {
  color: var(--dark-text);
  border-color: rgba(148, 163, 184, 0.7);
  background: rgba(255, 255, 255, 0.05);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 14px;
  min-height: 36px;
}

.btn-xl {
  padding: 16px 36px;
  font-size: 16px;
  min-height: 56px;
}

/* --- 8. Cards --- */
.card {
  background: var(--theme-bg-card);
  border: 1px solid var(--theme-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: all var(--dur-normal) var(--ease-out);
}

.card:hover {
  box-shadow: var(--theme-shadow-lg);
  transform: translateY(-2px);
  border-color: var(--theme-text-muted);
}

/* Dark mode: glass-morphism cards on unified bg */
[data-theme="dark"] .card {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

[data-theme="dark"] .card:hover {
  background: rgba(255,255,255,0.07);
  border-color: rgba(255,255,255,0.15);
  box-shadow: 0 8px 32px rgba(0,0,0,.4), 0 0 0 1px rgba(255,255,255,0.05);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
}

.card-grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-5);
}

.card .card-icon {
  font-size: 32px;
  margin-bottom: var(--space-4);
}

.card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.card p {
  color: var(--theme-text-secondary);
  font-size: 14px;
  line-height: 1.6;
}

/* --- 9. Code Block & Inline Code --- */
code {
  background: var(--theme-code-bg);
  color: var(--theme-code-text);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  font-family: var(--font-mono);
}

.code-block {
  background: var(--dark-bg-2);
  color: #E2E8F0;
  padding: var(--space-5) var(--space-6);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.7;
  overflow-x: auto;
  border: 1px solid rgba(255, 255, 255, 0.06);
  margin: var(--space-3) 0;
}

.code-block .comment {
  color: #64748B;
}

/* --- 10. Info Boxes --- */
.tip-box {
  background: var(--brand-50);
  border: 1px solid var(--brand-100);
  border-radius: var(--radius-md);
  padding: var(--space-4) var(--space-5);
  margin: var(--space-4) 0;
  font-size: 14px;
  color: var(--brand-700);
  line-height: 1.7;
}

.tip-box strong {
  display: block;
  margin-bottom: var(--space-1);
}

.warn-box {
  background: #FFFBEB;
  border: 1px solid #FDE68A;
  border-radius: var(--radius-md);
  padding: var(--space-4) var(--space-5);
  margin: var(--space-4) 0;
  font-size: 14px;
  color: #92400E;
  line-height: 1.7;
}

.warn-box strong {
  display: block;
  margin-bottom: var(--space-1);
}

.success-box {
  background: #F0FDF4;
  border: 1px solid #BBF7D0;
  border-radius: var(--radius-md);
  padding: var(--space-4) var(--space-5);
  margin: var(--space-4) 0;
  font-size: 14px;
  color: #166534;
  line-height: 1.7;
}

/* --- 11. FAQ / Details --- */
.faq-item {
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-3);
  overflow: hidden;
}

.faq-item summary {
  padding: var(--space-4) var(--space-5);
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  background: #fff;
  list-style: none;
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-height: 44px;
}

.faq-item summary::before {
  content: "▸";
  color: var(--brand-500);
  font-size: 12px;
  transition: transform var(--dur-fast) var(--ease-out);
  flex-shrink: 0;
}

.faq-item[open] summary::before {
  transform: rotate(90deg);
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-answer {
  padding: var(--space-4) var(--space-5);
  background: var(--gray-50);
  font-size: 14px;
  color: var(--gray-500);
  line-height: 1.8;
}

.faq-answer code {
  background: var(--gray-200);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 13px;
  color: var(--gray-800);
}

/* --- 12. Footer --- */
.site-footer {
  background: var(--theme-footer-bg);
  color: var(--theme-footer-text);
  padding: var(--space-12) 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
}

.footer-links {
  display: flex;
  list-style: none;
  gap: var(--space-6);
}

.footer-links a {
  color: var(--theme-footer-text);
  font-size: 14px;
}

.footer-links a:hover {
  color: var(--theme-text);
}

/* --- 13. Utility --- */
.text-center { text-align: center; }
.text-muted { color: var(--gray-500); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

/* --- 14. Responsive --- */
@media (max-width: 768px) {
  :root {
    --space-20: 48px;
    --space-16: 40px;
  }

  .nav-links { display: none; }
  .nav-toggle { display: flex; align-items: center; justify-content: center; }

  /* Mobile nav open state */
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    padding: var(--space-4) var(--space-6);
    gap: 0;
    border-bottom: 1px solid var(--gray-200);
    box-shadow: var(--shadow-md);
  }

  .nav-links.open a {
    padding: var(--space-3) 0;
    border-bottom: 1px solid var(--gray-100);
  }

  /* Mobile dropdown */
  .nav-dropdown-menu {
    position: static !important;
    transform: none !important;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    min-width: auto;
    margin: 0;
    padding: 0;
    background: transparent;
    backdrop-filter: none;
    border: none;
    border-radius: 0;
    box-shadow: none;
    transition: none;
    height: 0;
    overflow: hidden;
  }

  .nav-links.open .nav-dropdown-menu {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    height: auto;
    overflow: visible;
  }

  .nav-links.open .nav-dropdown-menu li a {
    padding: var(--space-2) 0 var(--space-2) var(--space-6);
    font-size: 13px;
    border-bottom: 1px solid var(--gray-100);
    color: var(--theme-text-secondary);
  }

  .nav-links.open .nav-dropdown-menu li a:hover {
    background: transparent;
    color: var(--brand-500);
  }

  /* Hide dropdown arrow on mobile */
  .nav-dropdown > a::after {
    display: none;
  }

  .hero { min-height: auto; padding-top: calc(64px + var(--space-12)); padding-bottom: var(--space-10); }
  .hero-title { font-size: 36px; }
  .hero-desc { font-size: 16px; }
  .page-hero h1 { font-size: 28px; }

  .card-grid { grid-template-columns: 1fr; }
  .card-grid-2 { grid-template-columns: 1fr; }

  .hero-actions { flex-direction: column; align-items: center; }

  .hero-terminal { margin-left: var(--space-4); margin-right: var(--space-4); }

  .hero-trust { gap: var(--space-3); }
  .trust-divider { display: none; }

  .footer-inner {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }

  .footer-links { flex-wrap: wrap; justify-content: center; }
}

/* --- 15. Nav scroll behavior (JS hook) --- */
/* Add .scrolled class to .site-header on scroll via JS */

/* --- 16. Dark Mode — Unified Background (QClaw-inspired) --- */

/* Remove hero bottom fade in dark mode for seamless flow */
[data-theme="dark"] .hero::after {
  display: none;
}

/* Make hero blend seamlessly — no min-height gap */
[data-theme="dark"] .hero {
  padding-bottom: var(--space-16);
  min-height: auto;
}

/* All sections share the same deep dark bg */
[data-theme="dark"] .section-alt,
[data-theme="dark"] .section-white {
  background: #060A14;
}

/* Subtle section separator instead of bg color change */
[data-theme="dark"] .section {
  position: relative;
}

[data-theme="dark"] .section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(100%, 600px);
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.06) 50%, transparent 100%);
}

/* First section after hero — no top separator */
[data-theme="dark"] .hero + .section::before {
  display: none;
}

/* Decorative ambient glow for depth (like QClaw) */
[data-theme="dark"] .section-alt {
  position: relative;
}

[data-theme="dark"] .section-alt::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 800px;
  height: 400px;
  background: radial-gradient(ellipse, rgba(232,90,79,0.025) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

[data-theme="dark"] .section-alt > .container {
  position: relative;
  z-index: 1;
}

/* Section titles — claw red accent in dark mode */
[data-theme="dark"] .section-title {
  color: #F87171;
}

/* Dark mode button overrides for content sections */
[data-theme="dark"] .btn-outline-dark {
  color: #94A3B8;
  border-color: rgba(148,163,184,0.3);
  background: transparent;
}

[data-theme="dark"] .btn-outline-dark:hover {
  color: #F1F5F9;
  border-color: rgba(148,163,184,0.6);
  background: rgba(255,255,255,0.05);
}

/* Dark mode FAQ / details */
[data-theme="dark"] .faq-item {
  border-color: rgba(255,255,255,0.08);
}

[data-theme="dark"] .faq-item summary {
  background: rgba(255,255,255,0.03);
  color: var(--theme-text);
}

[data-theme="dark"] .faq-answer {
  background: rgba(255,255,255,0.02);
  color: var(--theme-text-secondary);
}

[data-theme="dark"] .faq-answer code {
  background: rgba(255,255,255,0.08);
  color: #E2E8F0;
}

/* Dark mode info boxes */
[data-theme="dark"] .tip-box {
  background: rgba(59,130,246,0.08);
  border-color: rgba(59,130,246,0.2);
  color: #93C5FD;
}

[data-theme="dark"] .warn-box {
  background: rgba(245,158,11,0.08);
  border-color: rgba(245,158,11,0.2);
  color: #FCD34D;
}

[data-theme="dark"] .success-box {
  background: rgba(16,185,129,0.08);
  border-color: rgba(16,185,129,0.2);
  color: #6EE7B7;
}

/* Dark mode mobile nav */
[data-theme="dark"] .nav-links.open {
  background: rgba(6,10,20,0.98);
  border-bottom-color: rgba(255,255,255,0.08);
}

[data-theme="dark"] .nav-links.open a {
  border-bottom-color: rgba(255,255,255,0.06);
  color: #94A3B8;
}

[data-theme="dark"] .nav-links.open a:hover,
[data-theme="dark"] .nav-links.open a.active {
  color: #F1F5F9;
}

[data-theme="dark"] .nav-links.open .nav-dropdown-menu li a {
  border-bottom-color: rgba(255,255,255,0.04);
  color: #64748B;
}

[data-theme="dark"] .nav-links.open .nav-dropdown-menu li a:hover,
[data-theme="dark"] .nav-links.open .nav-dropdown-menu li a.active {
  color: var(--brand-400);
}

/* Dark mode page-hero seamless */
[data-theme="dark"] .page-hero {
  background: linear-gradient(180deg, #060A14, #060A14);
}

[data-theme="dark"] .page-hero::after {
  display: none;
}

/* Footer seamless in dark mode */
[data-theme="dark"] .site-footer {
  border-top: 1px solid rgba(255,255,255,0.06);
}

/* --- 17. Dark Mode — Sub-page Component Overrides --- */

/* page-hero inline style overrides */
[data-theme="dark"] .page-hero h1 {
  color: #F1F5F9;
}
[data-theme="dark"] .page-hero p {
  color: #94A3B8;
}

/* about.html — about-section, value-card */
[data-theme="dark"] .about-section {
  border-bottom-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .about-section h2 {
  color: #F1F5F9;
}
[data-theme="dark"] .about-section p {
  color: #94A3B8;
}
[data-theme="dark"] .value-card {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}
[data-theme="dark"] .value-card:hover {
  background: rgba(255,255,255,0.07);
}
[data-theme="dark"] .value-card h4 {
  color: #F1F5F9;
}
[data-theme="dark"] .value-card p {
  color: #94A3B8;
}

/* tutorial.html — toc, t-section, channel-card */
[data-theme="dark"] .toc {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
}
[data-theme="dark"] .toc h3 {
  color: #94A3B8;
}
[data-theme="dark"] .t-section {
  border-bottom-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .t-section h2 {
  color: #F1F5F9;
}
[data-theme="dark"] .t-section .subtitle {
  color: #94A3B8;
}
[data-theme="dark"] .t-section p.body {
  color: #CBD5E1;
}
[data-theme="dark"] .channel-card {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
}
[data-theme="dark"] .channel-card h4 {
  color: #F1F5F9;
}
[data-theme="dark"] .channel-card p {
  color: #94A3B8;
}

/* advanced.html — adv-card, tags */
[data-theme="dark"] .adv-card {
  background: rgba(255,255,255,0.04);
  border-color: rgba(255,255,255,0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}
[data-theme="dark"] .adv-card:hover {
  background: rgba(255,255,255,0.07);
  border-color: rgba(255,255,255,0.15);
  box-shadow: 0 8px 32px rgba(0,0,0,.4);
}
[data-theme="dark"] .adv-card h3 {
  color: #F1F5F9;
}
[data-theme="dark"] .adv-card .desc {
  color: #94A3B8;
}
[data-theme="dark"] .adv-card ul {
  color: #CBD5E1;
}
[data-theme="dark"] .tag-power {
  background: rgba(239,68,68,0.1);
  color: #F87171;
}
[data-theme="dark"] .tag-team {
  background: rgba(16,185,129,0.1);
  color: #6EE7B7;
}
[data-theme="dark"] .tag-dev {
  background: rgba(234,88,12,0.1);
  color: #FB923C;
}
[data-theme="dark"] .tag-biz {
  background: rgba(147,51,234,0.1);
  color: #C084FC;
}

/* start.html — step-item, check-ok */
[data-theme="dark"] .step-item {
  border-bottom-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .step-body h3 {
  color: #F1F5F9;
}
[data-theme="dark"] .step-body p {
  color: #94A3B8;
}
[data-theme="dark"] .check-ok {
  background: rgba(16,185,129,0.08);
  border-color: rgba(16,185,129,0.2);
}
[data-theme="dark"] .check-ok p {
  color: #6EE7B7;
}

/* Platform pages — install-step, tabs */
[data-theme="dark"] .install-step-item {
  border-bottom-color: rgba(255,255,255,0.06);
}
[data-theme="dark"] .tab-btn {
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.1);
  color: #94A3B8;
}
[data-theme="dark"] .tab-btn.active {
  background: var(--brand-500);
  border-color: var(--brand-500);
  color: #fff;
}
[data-theme="dark"] .tab-btn:hover:not(.active) {
  background: rgba(255,255,255,0.1);
  color: #F1F5F9;
}

/* Inline code on dark bg */
[data-theme="dark"] code {
  background: rgba(255,255,255,0.08);
  color: #E2E8F0;
}

/* Tables in dark mode */
[data-theme="dark"] table {
  color: #F1F5F9;
}
[data-theme="dark"] th {
  background: rgba(255,255,255,0.06);
  border-color: rgba(255,255,255,0.1);
}
[data-theme="dark"] td {
  border-color: rgba(255,255,255,0.06);
}

/* 404 page in dark mode */
[data-theme="dark"] .error-page {
  background: #060A14;
}
[data-theme="dark"] .error-code {
  color: var(--brand-400);
}