/* ═══════════════════════════════════════════════
   AMGOO Global V2 — Design System
   深海蓝 + 中性灰 + 活力橙 | 移动端优先
   ═══════════════════════════════════════════════ */

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

:root {
  /* 深海蓝 */
  --blue-900: #0a1628;
  --blue-800: #0f2847;
  --blue-700: #143a66;
  --blue-600: #1a4d85;
  --blue-500: #2060a4;
  --blue-400: #3a7fc0;
  --blue-300: #6ba3d6;
  --blue-200: #a3c8ec;
  --blue-100: #dce8f5;

  /* 中性灰 */
  --gray-900: #1a1a2e;
  --gray-800: #2d2d44;
  --gray-700: #4a4a5a;
  --gray-600: #6b6b7b;
  --gray-500: #8e8e9e;
  --gray-400: #b0b0be;
  --gray-300: #d1d1da;
  --gray-200: #e8e8ee;
  --gray-100: #f4f4f7;
  --gray-50:  #fafafc;

  /* 活力橙 */
  --orange-600: #d4551a;
  --orange-500: #f5651a;
  --orange-400: #ff8a4c;
  --orange-300: #ffad7a;
  --orange-200: #ffd4b0;

  /* 语义色 */
  --success: #10b981;
  --warning: #f59e0b;
  --danger:  #ef4444;

  /* 字体 */
  --font-sans: 'Inter', 'Noto Sans SC', 'Noto Sans TC', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', Consolas, monospace;

  /* 间距 */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  /* 阴影 */
  --shadow-sm: 0 1px 3px rgba(10, 22, 40, 0.08);
  --shadow-md: 0 4px 12px rgba(10, 22, 40, 0.1);
  --shadow-lg: 0 8px 24px rgba(10, 22, 40, 0.12);
  --shadow-xl: 0 16px 48px rgba(10, 22, 40, 0.15);

  /* 过渡 */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;

  /* 容器 */
  --container-max: 1200px;
  --container-wide: 1400px;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--gray-900);
  background: #fff;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }
button { cursor: pointer; font-family: inherit; }
ul, ol { list-style: none; }

/* ── Container ── */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container-wide {
  max-width: var(--container-wide);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* ── Typography ── */
.heading-xl {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.heading-lg {
  font-size: clamp(1.5rem, 3.5vw, 2.5rem);
  font-weight: 700;
  line-height: 1.25;
}

.heading-md {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  font-weight: 600;
  line-height: 1.3;
}

.heading-sm {
  font-size: clamp(1.1rem, 2vw, 1.25rem);
  font-weight: 600;
  line-height: 1.4;
}

.text-body { font-size: 1rem; line-height: 1.7; }
.text-sm { font-size: 0.875rem; line-height: 1.6; }
.text-xs { font-size: 0.75rem; line-height: 1.5; }

.text-muted { color: var(--gray-600); }
.text-light { color: var(--gray-400); }

/* ── Section ── */
.section {
  padding: var(--space-4xl) 0;
}

.section-dark {
  background: var(--blue-900);
  color: #fff;
}

.section-gray {
  background: var(--gray-100);
}

.section-title {
  text-align: center;
  margin-bottom: var(--space-3xl);
}

.section-title h2 {
  margin-bottom: var(--space-md);
}

.section-title p {
  max-width: 640px;
  margin: 0 auto;
  color: var(--gray-600);
}

.section-dark .section-title p {
  color: var(--gray-300);
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 0.75rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  transition: all var(--transition-base);
  white-space: nowrap;
}

.btn-primary {
  background: var(--orange-500);
  color: #fff;
  border-color: var(--orange-500);
}

.btn-primary:hover {
  background: var(--orange-600);
  border-color: var(--orange-600);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 101, 26, 0.35);
}

.btn-secondary {
  background: transparent;
  color: #fff;
  border-color: rgba(255,255,255,0.5);
}

.btn-secondary:hover {
  background: rgba(255,255,255,0.1);
  border-color: #fff;
  transform: translateY(-2px);
}

.btn-outline {
  background: transparent;
  color: var(--blue-700);
  border-color: var(--blue-700);
}

.btn-outline:hover {
  background: var(--blue-700);
  color: #fff;
}

.btn-sm { padding: 0.5rem 1.25rem; font-size: 0.875rem; }
.btn-lg { padding: 1rem 2.25rem; font-size: 1.125rem; }

/* ── Cards ── */
.card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.card-dark {
  background: var(--blue-800);
  border: 1px solid rgba(255,255,255,0.08);
  color: #fff;
}

/* ── Grid ── */
.grid {
  display: grid;
  gap: var(--space-xl);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ── Data Card (数字卡片) ── */
.data-card {
  text-align: center;
  padding: var(--space-xl);
}

.data-card .number {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  color: var(--orange-500);
  line-height: 1.1;
}

.data-card .number .unit {
  font-size: 0.5em;
  font-weight: 600;
}

.data-card .label {
  margin-top: var(--space-sm);
  color: var(--gray-600);
  font-size: 0.95rem;
}

/* ── Badge ── */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-orange { background: var(--orange-200); color: var(--orange-600); }
.badge-blue { background: var(--blue-100); color: var(--blue-700); }

/* ── Icon wrapper ── */
.icon-box {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.icon-box-orange {
  background: linear-gradient(135deg, var(--orange-500), var(--orange-400));
  color: #fff;
}

.icon-box-blue {
  background: linear-gradient(135deg, var(--blue-600), var(--blue-400));
  color: #fff;
}

/* ── Divider ── */
.divider {
  height: 1px;
  background: var(--gray-200);
  margin: var(--space-xl) 0;
}

/* ═══════════════════════════════════════════════
   Responsive Breakpoints
   ═══════════════════════════════════════════════ */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .section { padding: var(--space-3xl) 0; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .container { padding: 0 var(--space-md); }
}