/* ==========================================================================
   CalfSystem (International) - Modern Design System
   Version: 3.3.1
   Build: 2026-06-14
   Author: Web Design Team
   ========================================================================== */

/* 引入思源黑体（Noto Sans SC）开源字体，替代微软雅黑等版权字体 - 本地自托管 */
@import url('noto-sans-sc.css');

/* ============================================
   1. DESIGN TOKENS
   ============================================ */
:root {
  /* ----- Color Palette ----- */
  /* Brand */
  --brand-50:  #EFF6FF;
  --brand-100: #DBEAFE;
  --brand-200: #BFDBFE;
  --brand-300: #93C5FD;
  --brand-400: #60A5FA;
  --brand-500: #3B82F6;
  --brand-600: #2563EB;
  --brand-700: #1D4ED8;
  --brand-800: #1E40AF;
  --brand-900: #1E3A8A;
  --brand-950: #172554;

  /* Accent (orange / electric) */
  --accent-50:  #FFF7ED;
  --accent-100: #FFEDD5;
  --accent-300: #FDBA74;
  --accent-500: #F97316;
  --accent-600: #EA580C;
  --accent-700: #C2410C;

  /* Neutrals (cool gray) */
  --gray-50:  #F8FAFC;
  --gray-100: #F1F5F9;
  --gray-200: #E2E8F0;
  --gray-300: #CBD5E1;
  --gray-400: #94A3B8;
  --gray-500: #64748B;
  --gray-600: #475569;
  --gray-700: #334155;
  --gray-800: #1E293B;
  --gray-900: #0F172A;
  --gray-950: #020617;

  /* Semantic */
  --success: #10B981;
  --success-light: #D1FAE5;
  --warning: #F59E0B;
  --warning-light: #FEF3C7;
  --error:   #EF4444;
  --error-light: #FEE2E2;
  --info:    #06B6D4;

  /* Semantic mapping (light theme default) */
  --color-bg:           #FFFFFF;
  --color-bg-subtle:    var(--gray-50);
  --color-bg-elevated:  #FFFFFF;
  --color-bg-muted:     var(--gray-100);
  --color-bg-inverse:   var(--gray-900);

  --color-text:         var(--gray-900);
  --color-text-muted:   var(--gray-600);
  --color-text-subtle:  var(--gray-500);
  --color-text-inverse: #FFFFFF;

  --color-border:       var(--gray-200);
  --color-border-strong:var(--gray-300);
  --color-divider:      var(--gray-200);

  /* Surfaces with glass effect */
  --color-glass-bg:     rgba(255, 255, 255, 0.7);
  --color-glass-border: rgba(255, 255, 255, 0.3);

  /* Brand usage */
  --color-primary:        var(--brand-600);
  --color-primary-hover:  var(--brand-700);
  --color-primary-soft:   var(--brand-50);
  --color-on-primary:     #FFFFFF;

  /* Gradients */
  --gradient-brand:    linear-gradient(135deg, #1E40AF 0%, #3B82F6 50%, #60A5FA 100%);
  --gradient-hero:     linear-gradient(135deg, #0F172A 0%, #1E3A8A 50%, #2563EB 100%);
  --gradient-mesh:     radial-gradient(at 0% 0%, #1E40AF 0px, transparent 50%),
                       radial-gradient(at 100% 0%, #7C3AED 0px, transparent 50%),
                       radial-gradient(at 50% 100%, #3B82F6 0px, transparent 50%);
  --gradient-accent:   linear-gradient(135deg, #F97316 0%, #FB923C 100%);
  --gradient-subtle:   linear-gradient(180deg, #F8FAFC 0%, #FFFFFF 100%);

  /* ----- Typography ----- */
  --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont,
               'Helvetica Neue', Arial, sans-serif;
  --font-display: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', Monaco, Consolas, monospace;

  /* Type scale (modular 1.250) */
  --text-xs:   0.75rem;     /* 12 */
  --text-sm:   0.875rem;    /* 14 */
  --text-base: 1rem;        /* 16 */
  --text-lg:   1.125rem;    /* 18 */
  --text-xl:   1.25rem;     /* 20 */
  --text-2xl:  1.5rem;      /* 24 */
  --text-3xl:  1.875rem;    /* 30 */
  --text-4xl:  2.25rem;     /* 36 */
  --text-5xl:  3rem;        /* 48 */
  --text-6xl:  3.75rem;     /* 60 */
  --text-7xl:  4.5rem;      /* 72 */

  /* Spacing (4px base) */
  --space-0:  0;
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radii */
  --radius-sm:   6px;
  --radius-md:   10px;
  --radius-lg:   16px;
  --radius-xl:   24px;
  --radius-2xl:  32px;
  --radius-full: 9999px;

  /* Shadows (modern, soft) */
  --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.04);
  --shadow-sm: 0 1px 3px 0 rgba(15, 23, 42, 0.06), 0 1px 2px -1px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 8px -2px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 12px 24px -6px rgba(15, 23, 42, 0.10), 0 4px 8px -4px rgba(15, 23, 42, 0.04);
  --shadow-xl: 0 24px 48px -12px rgba(15, 23, 42, 0.18), 0 8px 16px -4px rgba(15, 23, 42, 0.06);
  --shadow-2xl: 0 32px 64px -16px rgba(15, 23, 42, 0.24);
  --shadow-glow: 0 0 0 4px rgba(37, 99, 235, 0.12);
  --shadow-glow-strong: 0 0 0 8px rgba(37, 99, 235, 0.18);

  /* Transitions */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --duration-fast: 150ms;
  --duration: 250ms;
  --duration-slow: 400ms;

  /* Layout */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1200px;
  --container-2xl: 1400px;
  --nav-height: 72px;

  /* Z-index */
  --z-base: 1;
  --z-elevated: 10;
  --z-sticky: 100;
  --z-overlay: 1000;
  --z-modal: 10000;
}

/* Dark theme */
[data-theme="dark"] {
  --color-bg:           var(--gray-950);
  --color-bg-subtle:    var(--gray-900);
  --color-bg-elevated:  var(--gray-900);
  --color-bg-muted:     var(--gray-800);
  --color-bg-inverse:   #FFFFFF;

  --color-text:         var(--gray-50);
  --color-text-muted:   var(--gray-400);
  --color-text-subtle:  var(--gray-500);
  --color-text-inverse: var(--gray-900);

  --color-border:       var(--gray-800);
  --color-border-strong:var(--gray-700);
  --color-divider:      var(--gray-800);

  --color-glass-bg:     rgba(15, 23, 42, 0.7);
  --color-glass-border: rgba(255, 255, 255, 0.08);

  --color-primary-soft: rgba(37, 99, 235, 0.15);

  --gradient-subtle:   linear-gradient(180deg, #0F172A 0%, #020617 100%);

  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.2);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 8px -2px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 24px -6px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 24px 48px -12px rgba(0, 0, 0, 0.6);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg:           var(--gray-950);
    --color-bg-subtle:    var(--gray-900);
    --color-bg-elevated:  var(--gray-900);
    --color-bg-muted:     var(--gray-800);
    --color-text:         var(--gray-50);
    --color-text-muted:   var(--gray-400);
    --color-text-subtle:  var(--gray-500);
    --color-border:       var(--gray-800);
    --color-primary-soft: rgba(37, 99, 235, 0.15);
    --gradient-subtle:   linear-gradient(180deg, #0F172A 0%, #020617 100%);
  }
}

/* ============================================
   2. RESET & BASE
   ============================================ */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }

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

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  transition: background var(--duration) var(--ease-out), color var(--duration) var(--ease-out);
}

img, svg, video { display: block; max-width: 100%; height: auto; }
button { font: inherit; cursor: pointer; background: none; border: none; color: inherit; }
a { color: inherit; text-decoration: none; }

::selection { background: var(--color-primary); color: var(--color-on-primary); }

/* Focus visible (accessibility) */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ============================================
   3. TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.025em;
  color: var(--color-text);
}

h1 { font-size: clamp(2.25rem, 5vw, var(--text-6xl)); font-weight: 800; letter-spacing: -0.04em; }
h2 { font-size: clamp(1.875rem, 4vw, var(--text-4xl)); font-weight: 700; }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); font-weight: 600; }
h5 { font-size: var(--text-lg); font-weight: 600; }
h6 { font-size: var(--text-base); font-weight: 600; }

p { color: var(--color-text-muted); line-height: 1.7; }

.text-gradient {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-muted { color: var(--color-text-muted); }
.text-subtle { color: var(--color-text-subtle); }
.text-center { text-align: center; }
.text-balance { text-wrap: balance; }

/* ============================================
   4. LAYOUT
   ============================================ */
.container {
  width: 100%;
  max-width: var(--container-xl);
  margin: 0 auto;
  padding: 0 var(--space-6);
}
.container-sm { max-width: var(--container-sm); }
.container-lg { max-width: var(--container-lg); margin: 0 auto; padding: 0 var(--space-6); }
.container-2xl { max-width: var(--container-2xl); margin: 0 auto; padding: 0 var(--space-6); }

.section {
  padding: clamp(var(--space-12), 8vw, var(--space-32)) 0;
  position: relative;
}
.section-sm { padding: clamp(var(--space-8), 5vw, var(--space-16)) 0; }
.section-lg { padding: clamp(var(--space-16), 10vw, var(--space-32)) 0; }

.section-header {
  text-align: center;
  max-width: 720px;
  margin: 0 auto var(--space-16);
}
.section-eyebrow {
  display: inline-block;
  font-size: var(--text-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}
.section-title {
  margin-bottom: var(--space-4);
  text-wrap: balance;
}
.section-subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  text-wrap: balance;
}

/* ============================================
   5. BUTTONS
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-base);
  font-weight: 600;
  line-height: 1.2;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--duration-fast) var(--ease-out);
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
  position: relative;
  overflow: hidden;
}

.btn:focus-visible { box-shadow: var(--shadow-glow); outline: none; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* Primary (gradient) */
.btn-primary {
  background: var(--gradient-brand);
  color: #FFFFFF;
  box-shadow: var(--shadow-md);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  filter: brightness(1.05);
}

/* Accent (orange) */
.btn-accent {
  background: var(--gradient-accent);
  color: #FFFFFF;
  box-shadow: var(--shadow-md);
}
.btn-accent:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }

/* Secondary (outline) */
.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border-strong);
}
.btn-secondary:hover {
  background: var(--color-bg-muted);
  border-color: var(--color-text-muted);
}

/* Ghost (text) */
.btn-ghost {
  background: transparent;
  color: var(--color-primary);
  padding: var(--space-2) var(--space-3);
}
.btn-ghost:hover { background: var(--color-primary-soft); }

/* Sizes */
.btn-sm { padding: var(--space-2) var(--space-4); font-size: var(--text-sm); }
.btn-lg { padding: var(--space-4) var(--space-8); font-size: var(--text-lg); }
.btn-xl { padding: var(--space-5) var(--space-10); font-size: var(--text-lg); font-weight: 700; }

/* Full width */
.btn-block { width: 100%; }

/* Icon-only */
.btn-icon {
  padding: var(--space-3);
  width: 44px;
  height: 44px;
}

/* Group */
.btn-group { display: inline-flex; gap: var(--space-3); flex-wrap: wrap; }

/* ============================================
   6. CARDS
   ============================================ */
.card {
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: all var(--duration) var(--ease-out);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-primary-soft);
}

.card-feature {
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all var(--duration) var(--ease-out);
  position: relative;
  overflow: hidden;
}
.card-feature::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--gradient-brand);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--duration) var(--ease-out);
}
.card-feature:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
  border-color: transparent;
}
.card-feature:hover::before { transform: scaleX(1); }

/* Glass card */
.card-glass {
  background: var(--color-glass-bg);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid var(--color-glass-border);
}

/* ============================================
   7. HEADER & NAVIGATION
   ============================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: var(--color-glass-bg);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--color-border);
  transition: all var(--duration) var(--ease-out);
}

.site-header.scrolled {
  background: var(--color-bg);
  box-shadow: var(--shadow-sm);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--nav-height);
  gap: var(--space-8);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-weight: 800;
  font-size: var(--text-lg);
  letter-spacing: -0.02em;
  color: var(--color-text);
}
.brand img { height: 36px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-name { font-size: var(--text-base); font-weight: 800; }
.brand-tagline { font-size: var(--text-xs); color: var(--color-text-muted); font-weight: 500; }

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-link {
  position: relative;
  padding: var(--space-2) var(--space-4);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  border-radius: var(--radius-md);
  transition: all var(--duration-fast) var(--ease-out);
}
.nav-link:hover { color: var(--color-text); background: var(--color-bg-muted); }
.nav-link.active { color: var(--color-primary); background: var(--color-primary-soft); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.theme-toggle {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  transition: all var(--duration-fast);
}
.theme-toggle:hover { color: var(--color-text); background: var(--color-bg-muted); }
.theme-toggle svg { width: 18px; height: 18px; }

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--color-text);
}
.menu-toggle svg { width: 22px; height: 22px; }

/* Mobile menu */
@media (max-width: 1024px) {
  .menu-toggle { display: flex; }
  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--color-bg-elevated);
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-4);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--duration) var(--ease-out), opacity var(--duration);
  }
  .nav-menu.active { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .nav-link { padding: var(--space-4); font-size: var(--text-base); }
  .nav-actions .btn { display: none; }
  .nav-actions .theme-toggle { display: flex; }
}

/* ============================================
   8. HERO
   ============================================ */
.hero {
  position: relative;
  padding: clamp(var(--space-16), 12vw, var(--space-32)) 0 clamp(var(--space-16), 10vw, var(--space-24));
  overflow: hidden;
  isolation: isolate;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: var(--gradient-hero);
  z-index: -2;
}

.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-mesh);
  opacity: 0.6;
  z-index: -1;
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(255,255,255,0.15) 1px, transparent 0);
  background-size: 32px 32px;
  opacity: 0.3;
  z-index: -1;
}

.hero-content {
  max-width: 880px;
  margin: 0 auto;
  text-align: center;
  color: #FFFFFF;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 500;
  color: rgba(255, 255, 255, 0.95);
  margin-bottom: var(--space-6);
  animation: fadeInUp 0.6s var(--ease-out);
}
.hero-eyebrow .badge-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-500);
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.04em;
  color: #FFFFFF;
  margin-bottom: var(--space-6);
  text-wrap: balance;
  animation: fadeInUp 0.6s 0.1s var(--ease-out) both;
}
.hero-title .highlight {
  background: linear-gradient(135deg, #60A5FA 0%, #93C5FD 50%, #FFFFFF 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(var(--text-lg), 2vw, var(--text-xl));
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: var(--space-10);
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  text-wrap: balance;
  animation: fadeInUp 0.6s 0.2s var(--ease-out) both;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  justify-content: center;
  margin-bottom: var(--space-10);
  animation: fadeInUp 0.6s 0.3s var(--ease-out) both;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-6) var(--space-10);
  font-size: var(--text-sm);
  color: rgba(255, 255, 255, 0.75);
  animation: fadeInUp 0.6s 0.4s var(--ease-out) both;
}
.hero-meta-item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}
.hero-meta-item svg { width: 16px; height: 16px; color: #60A5FA; }

/* Hero variants (per page) */
.hero-ai { background: linear-gradient(135deg, #1E1B4B 0%, #4F46E5 50%, #7C3AED 100%); }
.hero-pricing { background: linear-gradient(135deg, #1E1B4B 0%, #312E81 50%, #6366F1 100%); }
.hero-about { background: linear-gradient(135deg, #0F172A 0%, #1E293B 50%, #334155 100%); }
.hero-contact { background: linear-gradient(135deg, #064E3B 0%, #047857 50%, #10B981 100%); }
.hero-help { background: linear-gradient(135deg, #4C1D95 0%, #6D28D9 50%, #8B5CF6 100%); }
.hero-download { background: linear-gradient(135deg, #0C4A6E 0%, #0369A1 50%, #0EA5E9 100%); }
.hero-features { background: linear-gradient(135deg, #1E3A8A 0%, #2563EB 50%, #3B82F6 100%); }

/* ============================================
   9. STATS / NUMBERS
   ============================================ */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-8);
  padding: var(--space-12) 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}
.stat {
  text-align: center;
}
.stat-value {
  font-size: clamp(var(--text-3xl), 4vw, var(--text-5xl));
  font-weight: 800;
  letter-spacing: -0.03em;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin-bottom: var(--space-2);
}
.stat-label {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-weight: 500;
}

/* ============================================
   10. FEATURES GRID
   ============================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-6);
}

.feature {
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  transition: all var(--duration) var(--ease-out);
  position: relative;
  overflow: hidden;
}
.feature:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-primary-soft);
}

.feature-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-5);
  transition: all var(--duration) var(--ease-out);
}
.feature:hover .feature-icon {
  background: var(--gradient-brand);
  color: #FFFFFF;
  transform: scale(1.05) rotate(-3deg);
}
.feature-icon svg { width: 28px; height: 28px; }

.feature-title {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}
.feature-description {
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  line-height: 1.6;
}

/* ============================================
   11. PRICING
   ============================================ */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-6);
  max-width: var(--container-2xl);
  margin: 0 auto;
}

.pricing-card {
  position: relative;
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  display: flex;
  flex-direction: column;
  transition: all var(--duration) var(--ease-out);
}
.pricing-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
}

.pricing-card.featured {
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-lg);
  transform: scale(1.02);
}
.pricing-card.featured:hover { transform: scale(1.02) translateY(-6px); }

.pricing-badge {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--gradient-accent);
  color: #FFFFFF;
  font-size: var(--text-xs);
  font-weight: 700;
  padding: var(--space-1) var(--space-4);
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pricing-name {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-2);
  color: var(--color-text);
}
.pricing-description {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  min-height: 2.5em;
  margin-bottom: var(--space-6);
}

.pricing-price {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
  margin-bottom: var(--space-2);
}
.pricing-price-currency { font-size: var(--text-xl); font-weight: 600; color: var(--color-text); }
.pricing-price-amount {
  font-size: clamp(var(--text-4xl), 5vw, var(--text-5xl));
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1;
  color: var(--color-text);
}
.pricing-price-period { font-size: var(--text-sm); color: var(--color-text-muted); }
.pricing-price-note { font-size: var(--text-xs); color: var(--color-text-subtle); margin-bottom: var(--space-6); }

.pricing-features {
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-8);
  flex-grow: 1;
}
.pricing-features li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-2) 0;
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
}
.pricing-features li svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  margin-top: 2px;
  color: var(--success);
}
.pricing-features li.disabled {
  color: var(--color-text-subtle);
  text-decoration: line-through;
}
.pricing-features li.disabled svg { color: var(--color-text-subtle); }

/* Pricing toggle */
.pricing-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  margin-bottom: var(--space-12);
}
.pricing-toggle-switch {
  position: relative;
  width: 56px;
  height: 28px;
  background: var(--color-bg-muted);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background var(--duration) var(--ease-out);
}
.pricing-toggle-switch.active { background: var(--color-primary); }
.pricing-toggle-switch::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 24px;
  height: 24px;
  background: #FFFFFF;
  border-radius: 50%;
  transition: transform var(--duration) var(--ease-out);
  box-shadow: var(--shadow-sm);
}
.pricing-toggle-switch.active::after { transform: translateX(28px); }
.pricing-toggle-label {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
}
.pricing-toggle-label.active { color: var(--color-text); font-weight: 600; }

/* ============================================
   12. TESTIMONIALS
   ============================================ */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-6);
}

.testimonial {
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  position: relative;
  transition: all var(--duration) var(--ease-out);
}
.testimonial:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}
.testimonial-quote {
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-text);
  margin-bottom: var(--space-6);
  font-style: italic;
}
.testimonial-author {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.testimonial-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient-brand);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #FFFFFF;
  font-weight: 700;
  font-size: var(--text-base);
}
.testimonial-name {
  font-weight: 600;
  font-size: var(--text-sm);
  color: var(--color-text);
}
.testimonial-role {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* ============================================
   13. FAQ
   ============================================ */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}
.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  margin-bottom: var(--space-3);
  overflow: hidden;
  transition: all var(--duration) var(--ease-out);
}
.faq-item:hover { border-color: var(--color-primary-soft); }
.faq-item.open { box-shadow: var(--shadow-md); }
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: var(--space-5) var(--space-6);
  font-size: var(--text-base);
  font-weight: 600;
  text-align: left;
  color: var(--color-text);
  cursor: pointer;
  transition: color var(--duration-fast);
}
.faq-question:hover { color: var(--color-primary); }
.faq-icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  margin-left: var(--space-4);
  color: var(--color-text-muted);
  transition: transform var(--duration) var(--ease-out);
}
.faq-item.open .faq-icon { transform: rotate(45deg); color: var(--color-primary); }
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--duration) var(--ease-out);
}
.faq-item.open .faq-answer { max-height: 500px; }
.faq-answer-content {
  padding: 0 var(--space-6) var(--space-5);
  color: var(--color-text-muted);
  line-height: 1.7;
}

/* ============================================
   14. CTA BANNER
   ============================================ */
.cta-banner {
  position: relative;
  padding: clamp(var(--space-12), 8vw, var(--space-20)) var(--space-6);
  background: var(--gradient-hero);
  border-radius: var(--radius-2xl);
  text-align: center;
  color: #FFFFFF;
  overflow: hidden;
  isolation: isolate;
  margin: var(--space-16) auto;
  max-width: var(--container-2xl);
}
.cta-banner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-mesh);
  opacity: 0.5;
  z-index: -1;
}
.cta-banner-title {
  font-size: clamp(var(--text-2xl), 4vw, var(--text-4xl));
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-4);
  text-wrap: balance;
}
.cta-banner-subtitle {
  font-size: var(--text-lg);
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: var(--space-8);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.cta-banner-actions { display: inline-flex; gap: var(--space-4); flex-wrap: wrap; justify-content: center; }

/* ============================================
   15. FOOTER
   ============================================ */
.site-footer {
  background: var(--gray-950);
  color: var(--gray-300);
  padding: var(--space-20) 0 var(--space-8);
  margin-top: var(--space-24);
}
.site-footer a { color: var(--gray-400); transition: color var(--duration-fast); }
.site-footer a:hover { color: #FFFFFF; }

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(4, 1fr);
  gap: var(--space-12);
  margin-bottom: var(--space-16);
}
@media (max-width: 1024px) { .footer-grid { grid-template-columns: 1fr 1fr; gap: var(--space-8); } }
@media (max-width: 640px) { .footer-grid { grid-template-columns: 1fr; gap: var(--space-8); } }

.footer-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}
.footer-brand img { height: 32px; filter: brightness(0) invert(1); }
.footer-brand-name {
  font-size: var(--text-lg);
  font-weight: 800;
  color: #FFFFFF;
}
.footer-tagline {
  color: var(--gray-400);
  font-size: var(--text-sm);
  line-height: 1.6;
  margin-bottom: var(--space-4);
  max-width: 280px;
}
.footer-social {
  display: flex;
  gap: var(--space-3);
}
.footer-social a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all var(--duration-fast);
}
.footer-social a:hover { background: rgba(255, 255, 255, 0.1); border-color: rgba(255, 255, 255, 0.2); }
.footer-social svg { width: 18px; height: 18px; }

.footer-col-title {
  font-size: var(--text-sm);
  font-weight: 600;
  color: #FFFFFF;
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.footer-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.footer-list a {
  font-size: var(--text-sm);
  color: var(--gray-400);
  transition: color var(--duration-fast);
}
.footer-list a:hover { color: #FFFFFF; }

.footer-qrcode {
  width: 100px;
  height: 100px;
  border-radius: var(--radius-md);
  border: 4px solid #FFFFFF;
  background: #FFFFFF;
  margin-top: var(--space-2);
}

.footer-bottom {
  padding-top: var(--space-8);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-4);
  font-size: var(--text-xs);
  color: var(--gray-500);
}
.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}
.footer-legal a { font-size: var(--text-xs); color: var(--gray-500); }
.footer-legal a:hover { color: #FFFFFF; }

/* ============================================
   16. BADGES & TAGS
   ============================================ */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-3);
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
  background: var(--color-bg-muted);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.badge-primary { background: var(--color-primary-soft); color: var(--color-primary); }
.badge-success { background: var(--success-light); color: var(--success); }
.badge-warning { background: var(--warning-light); color: var(--warning); }
.badge-error { background: var(--error-light); color: var(--error); }
.badge-outline { background: transparent; border: 1px solid var(--color-border-strong); }

/* ============================================
   17. FORMS
   ============================================ */
.form-group { margin-bottom: var(--space-5); }
.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.form-input, .form-textarea, .form-select {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  font-family: inherit;
  color: var(--color-text);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-md);
  transition: all var(--duration-fast) var(--ease-out);
}
.form-input:focus, .form-textarea:focus, .form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: var(--shadow-glow);
}
.form-textarea { min-height: 120px; resize: vertical; }
.form-help { font-size: var(--text-xs); color: var(--color-text-muted); margin-top: var(--space-1); }
.form-error { font-size: var(--text-xs); color: var(--error); margin-top: var(--space-1); }

/* ============================================
   18. ANIMATIONS
   ============================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.5); opacity: 0; }
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}
@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.animate-fade-in { animation: fadeIn var(--duration-slow) var(--ease-out); }
.animate-fade-in-up { animation: fadeInUp var(--duration-slow) var(--ease-out); }
.animate-float { animation: float 3s var(--ease-in-out) infinite; }

/* Reveal on scroll (data-animate) */
[data-animate] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--duration-slow) var(--ease-out), transform var(--duration-slow) var(--ease-out);
}
[data-animate].visible { opacity: 1; transform: translateY(0); }

/* ============================================
   19. UTILITIES
   ============================================ */
.hidden { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.mt-1 { margin-top: var(--space-1); }
.mt-2 { margin-top: var(--space-2); }
.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); }
.mt-16 { margin-top: var(--space-16); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }

/* ============================================
   20. RESPONSIVE
   ============================================ */
@media (max-width: 768px) {
  html { font-size: 15px; }
  .container { padding: 0 var(--space-4); }
  .section { padding: var(--space-12) 0; }
  .hero-cta { flex-direction: column; align-items: stretch; }
  .hero-cta .btn { width: 100%; }
  .footer-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  html { font-size: 14px; }
  .pricing-card.featured { transform: none; }
  .pricing-card.featured:hover { transform: translateY(-4px); }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ============================================
   V2.5.3 Visual Enhancements (additive, no breakage)
   ============================================ */

/* Custom scrollbar */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: var(--color-bg-subtle, #f8f9fa);
}
::-webkit-scrollbar-thumb {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(135deg, #5a6fd8 0%, #6a3f92 100%);
}

/* Selection highlight */
::selection {
  background: rgba(102, 126, 234, 0.25);
  color: inherit;
}
::-moz-selection {
  background: rgba(102, 126, 234, 0.25);
  color: inherit;
}

/* Hero section: mesh gradient overlays */
.hero {
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.15) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 1;
}
.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(118, 75, 162, 0.25) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
  z-index: 1;
}
.hero .container {
  position: relative;
  z-index: 2;
}

/* Button: ripple effect */
.btn {
  position: relative;
  overflow: hidden;
}
.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
  pointer-events: none;
}
.btn:hover::before {
  width: 300px;
  height: 300px;
}

/* Primary button: gradient + glow */
.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  background-size: 200% 200%;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
  transition: all 0.3s ease;
}
.btn-primary:hover {
  background-position: 100% 100%;
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.5);
  transform: translateY(-2px);
}

/* Pricing card: featured glow */
.pricing-card.featured {
  position: relative;
  background: linear-gradient(180deg, #ffffff 0%, #f8f9ff 100%);
  border: 2px solid transparent;
  background-clip: padding-box;
}
.pricing-card.featured::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  background: linear-gradient(135deg, #667eea, #764ba2);
  border-radius: inherit;
  z-index: -1;
  opacity: 0.5;
}
.pricing-card.featured:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 50px rgba(102, 126, 234, 0.25);
}

/* Price number: gradient text */
.pricing-price {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Card hover enhancement */
.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.08);
}

/* Feature icon: gradient background */
.feature-icon, .feature-card .icon {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  box-shadow: 0 8px 20px rgba(102, 126, 234, 0.3);
}

/* Link: animated underline */
a {
  position: relative;
  text-decoration: none;
}
a:hover {
  text-decoration: none;
}
.footer a, .nav-links a,
.site-footer a, .nav-link,
.footer-list a, .footer-legal a {
  background-image: linear-gradient(135deg, #667eea, #764ba2);
  background-size: 0% 2px;
  background-position: 0 100%;
  background-repeat: no-repeat;
  transition: background-size 0.3s ease;
}
.footer a:hover, .nav-links a:hover,
.site-footer a:hover, .nav-link:hover,
.footer-list a:hover, .footer-legal a:hover {
  background-size: 100% 2px;
}

/* Glass effect enhancement */
.glass {
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  background: rgba(255, 255, 255, 0.7);
  border-bottom: 1px solid rgba(102, 126, 234, 0.1);
}

/* Gradient text utility */
.text-gradient {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Section tinted background utility */
.section-tinted {
  background: linear-gradient(180deg, #f8f9ff 0%, #ffffff 100%);
}

/* Responsive: mobile button full-width */
@media (max-width: 480px) {
  .btn-lg {
    width: 100%;
    display: block;
  }
  .hero-cta {
    flex-direction: column;
    gap: var(--space-3);
  }
}

/* Dark mode enhancements */
[data-theme="dark"] ::selection {
  background: rgba(102, 126, 234, 0.4);
  color: white;
}
[data-theme="dark"] .glass {
  background: rgba(30, 30, 40, 0.7);
  border-bottom: 1px solid rgba(102, 126, 234, 0.2);
}