:root {
  /* sidebar (kept dark — persistent wayfinding anchor, matches reference) */
  --sidebar-bg: #060813;
  --sidebar-border: rgba(0, 240, 255, 0.08);
  --sidebar-hover: rgba(0, 240, 255, 0.05);
  --sidebar-active: rgba(0, 240, 255, 0.08);
  --sidebar-text: #94a3b8;
  --sidebar-text-active: #ffffff;
  --sidebar-brand: #00f0ff;

  /* main content surfaces (sleek dark mode - default) */
  --surface-0: #030712;
  --surface-1: #090d1a;
  --surface-2: rgba(15, 23, 42, 0.65);
  --surface-3: #1e293b;
  --border: rgba(0, 240, 255, 0.1);
  --border-strong: rgba(0, 240, 255, 0.2);

  /* RGB triplets of the surface tones above, for rgba(var(--x-rgb), alpha)
     usage where layout.css needs a surface color at a custom opacity —
     keeps those spots theme-aware instead of hardcoding a fixed dark literal */
  --surface-0-rgb: 3, 7, 18;
  --surface-1-rgb: 9, 13, 26;
  --surface-2-rgb: 15, 23, 42;
  --surface-3-rgb: 30, 41, 59;

  /* ink */
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  /* accent (neon electric cyan/blue & purple) */
  --accent: #00f0ff;
  --accent-hover: #00d8e6;
  --accent-soft: rgba(0, 240, 255, 0.08);
  --accent-violet: #a855f7;
  --accent-violet-soft: rgba(168, 85, 247, 0.08);

  /* status triad (vibrant neon status colors suitable for dark background) */
  --status-good: #10b981;
  --status-good-soft: rgba(16, 185, 129, 0.08);
  --status-warning: #fbbf24;
  --status-warning-soft: rgba(251, 191, 36, 0.08);
  --status-warning-rgb: 251, 191, 36;
  --status-critical: #f43f5e;
  --status-critical-soft: rgba(244, 63, 94, 0.08);
  --status-critical-rgb: 244, 63, 94;
  --status-muted: #64748b;
  --status-muted-soft: rgba(100, 116, 139, 0.12);

  /* elevation (neon glow & dark shadows) */
  --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.05);
  --shadow-modal: 0 24px 64px rgba(0, 0, 0, 0.7), 0 0 24px rgba(0, 240, 255, 0.05);

  /* type */
  --font-ui: "Plex Sans Thai", "Segoe UI", sans-serif;
  --font-mono: "Plex Mono", "Plex Sans Thai", monospace;

  --text-xs: 12px;
  --text-sm: 13px;
  --text-base: 14px;
  --text-md: 16px;
  --text-lg: 20px;
  --text-xl: 28px;

  /* spacing */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;

  /* radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;

  --sidebar-width: 224px;
  --topbar-height: 56px;

  /* custom buttons text color and theme parameters */
  --btn-primary-text: #030712;
  --backdrop-blur: 16px;
  --mesh-opacity-purple: 0.12;
  --mesh-opacity-cyan: 0.08;
  --grid-line-opacity: 0.003;
}

html[data-theme="light"] {
  /* main content surfaces (sleek light mode) */
  --surface-0: #f1f5f9;
  --surface-1: #ffffff;
  --surface-2: rgba(255, 255, 255, 0.75);
  --surface-3: #e2e8f0;
  --border: rgba(47, 125, 225, 0.1);
  --border-strong: rgba(47, 125, 225, 0.25);

  --surface-0-rgb: 241, 245, 249;
  --surface-1-rgb: 255, 255, 255;
  --surface-2-rgb: 255, 255, 255;
  --surface-3-rgb: 226, 232, 240;

  /* ink */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;

  /* accent (maritime blue — primary actions, active nav, links, chart hue) */
  --accent: #2f7de1;
  --accent-hover: #1f68c9;
  --accent-soft: rgba(47, 125, 225, 0.08);
  --accent-violet: #7c5cd6;
  --accent-violet-soft: rgba(124, 92, 214, 0.08);

  /* status triad (vibrant but high contrast on light backgrounds) */
  --status-good: #0d9488;
  --status-good-soft: rgba(13, 148, 136, 0.08);
  --status-warning: #d97706;
  --status-warning-soft: rgba(217, 119, 6, 0.08);
  --status-warning-rgb: 217, 119, 6;
  --status-critical: #e11d48;
  --status-critical-soft: rgba(225, 29, 72, 0.08);
  --status-critical-rgb: 225, 29, 72;
  --status-muted: #94a3b8;
  --status-muted-soft: rgba(148, 163, 184, 0.12);

  /* elevation (softer shadows for light theme) */
  --shadow-card: 0 4px 20px rgba(15, 23, 42, 0.05), inset 0 1px 0 rgba(255, 255, 255, 0.8);
  --shadow-modal: 0 24px 64px rgba(15, 23, 42, 0.15), 0 0 24px rgba(47, 125, 225, 0.05);

  /* custom buttons text color and theme parameters */
  --btn-primary-text: #ffffff;
  --backdrop-blur: 12px;
  --mesh-opacity-purple: 0.04;
  --mesh-opacity-cyan: 0.02;
  --grid-line-opacity: 0.015;
}