/* BlooTube Voice 2026 — Apple iOS 18 Cupertino Design Tokens */
:root {
  /* ─── Apple Canvas & Materials (OLED Pure Black & Liquid Glass) ─── */
  --bt-bg-app: #000000;
  --bt-bg-surface: #121214;
  --bt-bg-card: rgba(28, 28, 30, 0.72);
  --bt-bg-card-opaque: #1C1C1E;
  --bt-bg-elevated: rgba(44, 44, 46, 0.70);
  --bt-bg-input: rgba(24, 24, 26, 0.85);
  --bt-bg-hover: rgba(255, 255, 255, 0.08);
  --bt-bg-active: rgba(255, 255, 255, 0.14);
  --bt-bg-glass: rgba(28, 28, 30, 0.78);
  --bt-bg-glass-card: rgba(28, 28, 30, 0.68);
  --bt-bg-glass-thick: rgba(28, 28, 30, 0.92);

  /* ─── Apple Human Interface Guidelines System Colors ─── */
  --bt-apple-blue: #007AFF;
  --bt-apple-indigo: #5856D6;
  --bt-apple-purple: #AF52DE;
  --bt-apple-pink: #FF2D55;
  --bt-apple-teal: #30B0C7;
  --bt-apple-mint: #00C7BE;
  --bt-apple-green: #34C759;
  --bt-apple-orange: #FF9500;
  --bt-apple-yellow: #FFCC00;
  --bt-apple-red: #FF3B30;

  /* Aliases mapped to Apple Palette */
  --bt-neon-cyan: #007AFF;
  --bt-neon-blue: #007AFF;
  --bt-neon-electric-blue: #5AC8FA;
  --bt-neon-indigo: #5856D6;
  --bt-neon-purple: #AF52DE;
  --bt-neon-violet: #AF52DE;
  --bt-neon-magenta: #AF52DE;
  --bt-neon-pink: #FF2D55;

  --bt-brand-cyan: #007AFF;
  --bt-brand-blue: #007AFF;
  --bt-brand-purple: #AF52DE;
  --bt-brand-violet: #AF52DE;
  --bt-brand-magenta: #AF52DE;

  /* ─── Apple Gradients & Material Vibrancy ─── */
  --bt-gradient-brand: linear-gradient(135deg, #007AFF 0%, #5856D6 50%, #AF52DE 100%);
  --bt-gradient-cyan-magenta: linear-gradient(90deg, #007AFF 0%, #5856D6 50%, #AF52DE 100%);
  --bt-gradient-cyan-violet: linear-gradient(90deg, #007AFF 0%, #5856D6 50%, #AF52DE 100%);
  --bt-gradient-btn: linear-gradient(180deg, #007AFF 0%, #0062D2 100%);
  --bt-gradient-card: linear-gradient(180deg, rgba(255, 255, 255, 0.05) 0%, rgba(255, 255, 255, 0.01) 100%);
  --bt-gradient-glass: linear-gradient(180deg, rgba(255, 255, 255, 0.10) 0%, rgba(255, 255, 255, 0.02) 100%);
  --bt-gradient-text: linear-gradient(180deg, #FFFFFF 30%, #A1A1A6 100%);

  /* ─── Specular Borders & Apple Shadows ─── */
  --bt-border-subtle: rgba(255, 255, 255, 0.08);
  --bt-border-strong: rgba(255, 255, 255, 0.16);
  --bt-border-brand: rgba(0, 122, 255, 0.40);
  --bt-border-violet: rgba(175, 82, 222, 0.40);
  --bt-border-magenta: rgba(175, 82, 222, 0.40);
  --bt-border-focus: #007AFF;

  /* Refined Apple Diffuse Shadows (no harsh neon glow) */
  --bt-glow-cyan: 0 4px 16px rgba(0, 122, 255, 0.28);
  --bt-glow-violet: 0 4px 16px rgba(175, 82, 222, 0.28);
  --bt-glow-magenta: 0 4px 16px rgba(175, 82, 222, 0.28);
  --bt-glow-btn: 0 4px 20px rgba(0, 122, 255, 0.35);

  --bt-shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --bt-shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --bt-shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.50);

  /* ─── Apple Typography Colors (SF Pro Hierarchy) ─── */
  --bt-text-primary: #FFFFFF;
  --bt-text-secondary: #8E8E93;
  --bt-text-dim: #636366;
  --bt-text-cyan: #007AFF;
  --bt-text-violet: #AF52DE;
  --bt-text-magenta: #AF52DE;

  /* ─── Apple Semantics ─── */
  --bt-success: #34C759;
  --bt-warning: #FF9500;
  --bt-error: #FF3B30;
  --bt-info: #007AFF;

  /* ─── Spacings & Metrics ─── */
  --bt-space-xs: 4px;
  --bt-space-sm: 8px;
  --bt-space-md: 12px;
  --bt-space-lg: 16px;
  --bt-space-xl: 20px;
  --bt-space-xxl: 24px;

  /* ─── Apple Squircles (Continuous Corners Scale) ─── */
  --bt-radius-sm: 10px;
  --bt-radius-md: 14px;
  --bt-radius-lg: 18px;
  --bt-radius-xl: 24px;
  --bt-radius-2xl: 32px;
  --bt-radius-pill: 999px;

  /* ─── Apple Control Heights ─── */
  --bt-control-sm: 32px;
  --bt-control-md: 40px;
  --bt-control-lg: 48px;
  --bt-control-hero: 52px;

  /* ─── Apple System Typography Stack ─── */
  --bt-family-ui: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  --bt-family-mono: "SF Mono", Menlo, Monaco, Consolas, monospace;

  /* ─── 2026 Liquid Glass & Refractive Caustics Tokens ─── */
  --bt-liquid-glass: rgba(30, 32, 38, 0.65);
  --bt-liquid-glass-thick: rgba(24, 26, 32, 0.85);
  --bt-liquid-specular-border: 1px solid rgba(255, 255, 255, 0.14);
  --bt-liquid-refract-bevel: inset 0 1px 1px 0 rgba(255, 255, 255, 0.25), inset 0 -1px 1px 0 rgba(0, 0, 0, 0.45);
  --bt-liquid-lens-shadow: 0 14px 40px -4px rgba(0, 0, 0, 0.65), 0 4px 12px -2px rgba(0, 0, 0, 0.35);
  --bt-liquid-pill-track: rgba(120, 120, 128, 0.24);
  --bt-liquid-pill-lens: linear-gradient(180deg, rgba(255, 255, 255, 0.95) 0%, rgba(215, 220, 230, 0.82) 100%);
  --bt-liquid-pill-shadow: 0 3px 10px rgba(0, 0, 0, 0.3), 0 1px 3px rgba(0, 0, 0, 0.2);

  /* ─── Apple Intelligence 2026 Chroma Aura ─── */
  --bt-chroma-aura: linear-gradient(135deg, #007AFF 0%, #AF52DE 35%, #FF2D55 70%, #5AC8FA 100%);
  --bt-chroma-glow: 0 0 25px rgba(0, 122, 255, 0.45), 0 0 45px rgba(175, 82, 222, 0.3);

  /* ─── Apple Spring Physics Timing Functions ─── */
  --bt-spring-tap: cubic-bezier(0.25, 1, 0.5, 1);
  --bt-spring-bounce: cubic-bezier(0.175, 0.885, 0.32, 1.275);
  --bt-spring-sheet: cubic-bezier(0.32, 0.72, 0, 1);
}