/* 主题 ② 深色高端商务 */
body.theme-dark {
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Inter, sans-serif;
  --maxw: 1140px;
  --gutter: 18px;
  --header-h: 64px;
  --radius: 12px;
  --radius-sm: 8px;
  --grid-gap: 16px;

  --bg: #0b0f14;
  --surface: #12181f;
  --text: #e8edf2;
  --muted: #8b9aab;
  --heading: #f1f5f9;
  --border: #243040;
  --link: #7cb8ff;
  --link-hover: #a8d0ff;

  --accent: #c9a227;
  --accent-ink: #0b0f14;

  --header-bg: rgba(11, 15, 20, 0.94);
  --header-blur: blur(14px);
  --nav-hover-bg: rgba(201, 162, 39, 0.1);
  --nav-active-bg: rgba(201, 162, 39, 0.18);
  --shadow-md: 0 16px 48px rgba(0, 0, 0, 0.45);

  --hero-title: #f8fafc;
  --hero-lead: #94a3b8;
  --hero-strong: #ffffff;

  --tag-border: #334155;
  --tag-bg: #1a2330;
  --tag-text: #cbd5e1;
  --code-bg: rgba(0, 0, 0, 0.35);

  --callout-border: #3d4f63;
  --callout-bg: #151d28;
  --callout-text: #cbd5e1;
  --callout-strong: #e2b84a;
  --callout-code-bg: rgba(0, 0, 0, 0.4);
  --callout-code-text: #93c5fd;

  --card-border: #243040;
  --card-bg: #12181f;
  --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.35);

  --codeblock-border: #334155;
  --codeblock-bg: #0a0e12;
  --codeblock-text: #cbd5e1;

  --footer-bg: #080b0e;
  --footer-text: #8b9aab;
  --footer-heading: #e8edf2;
  --footer-link: #8b9aab;

  --alert-error-bg: #3f1a1a;
  --alert-error-text: #fecaca;
  --alert-error-border: #7f1d1d;
  --alert-ok-bg: #0f2918;
  --alert-ok-text: #bbf7d0;
  --alert-ok-border: #14532d;
}

body.theme-dark .hero.hero-surface {
  background: radial-gradient(ellipse 100% 80% at 50% -30%, rgba(201, 162, 39, 0.12), transparent),
    linear-gradient(180deg, #12181f 0%, #0b0f14 100%);
  border-bottom: 1px solid var(--border);
}

body.theme-dark .section-alt {
  background: #0f1419;
}

body.theme-dark .select-mini,
body.theme-dark .btn,
body.theme-dark .input,
body.theme-dark .textarea {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border);
}

body.theme-dark .btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
  border-color: transparent;
}

body.theme-dark .btn-usdt {
  background: #26a17b;
  color: #fff;
  border-color: transparent;
}