/* ==========================================================================
   PIXIFLOW DESIGN SYSTEM - CSS CUSTOM PROPERTIES & TOKENS
   ========================================================================== */

:root {
  /* Brand Palette */
  --color-primary: #2563EB;
  --color-primary-hover: #1D4ED8;
  --color-primary-active: #1E40AF;
  --color-primary-light: #EFF6FF;
  
  --color-secondary: #0F172A;
  --color-secondary-hover: #1E293B;
  
  --color-accent: #14B8A6;
  --color-accent-hover: #0D9488;
  
  --color-success: #16A34A;
  --color-success-bg: #DCFCE7;
  --color-warning: #F59E0B;
  --color-warning-bg: #FEF3C7;
  --color-danger: #DC2626;
  --color-danger-bg: #FEE2E2;

  /* Neutral Scale (Light Theme) */
  --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;

  /* Semantic Theme Colors (Light Default) */
  --bg-app: var(--gray-50);
  --bg-surface: #FFFFFF;
  --bg-surface-elevated: #FFFFFF;
  --bg-surface-hover: var(--gray-100);
  --border-color: var(--gray-200);
  --border-color-hover: var(--gray-300);
  
  --text-main: var(--gray-900);
  --text-muted: var(--gray-600);
  --text-disabled: var(--gray-400);
  --text-inverse: #FFFFFF;

  --focus-ring-color: rgba(37, 99, 235, 0.4);

  /* Glassmorphism Defaults */
  --glass-bg: rgba(255, 255, 255, 0.85);
  --glass-border: rgba(226, 232, 240, 0.8);
  --glass-backdrop-blur: 12px;

  /* Typography Scale */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  --text-xs: clamp(0.7rem, 0.68rem + 0.1vw, 0.75rem);
  --text-sm: clamp(0.8rem, 0.78rem + 0.12vw, 0.875rem);
  --text-base: clamp(0.95rem, 0.92rem + 0.15vw, 1rem);
  --text-lg: clamp(1.1rem, 1.05rem + 0.25vw, 1.125rem);
  --text-xl: clamp(1.2rem, 1.12rem + 0.4vw, 1.25rem);
  --text-2xl: clamp(1.35rem, 1.22rem + 0.65vw, 1.5rem);
  --text-3xl: clamp(1.6rem, 1.4rem + 1vw, 1.875rem);
  --text-4xl: clamp(2.1rem, 1.8rem + 1.5vw, 2.25rem);
  --text-5xl: clamp(2.5rem, 2rem + 2.5vw, 3rem);

  /* Font Weights */
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;

  /* Line Heights */
  --leading-tight: 1.2;
  --leading-snug: 1.375;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;

  /* Spacing Tokens */
  --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;

  /* Border Radii */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows (Material Elevation) */
  --shadow-sm: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.03);
  --shadow-xl: 0 20px 25px -5px rgba(15, 23, 42, 0.1), 0 8px 10px -6px rgba(15, 23, 42, 0.04);
  --shadow-inner: inset 0 2px 4px 0 rgba(15, 23, 42, 0.06);

  /* Transitions */
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: 150ms var(--ease-in-out);
  --transition-normal: 250ms var(--ease-in-out);
  --transition-slow: 350ms var(--ease-in-out);

  /* Layering Z-Index */
  --z-back: -1;
  --z-base: 1;
  --z-sticky: 100;
  --z-dropdown: 200;
  --z-modal-backdrop: 500;
  --z-modal: 600;
  --z-toast: 700;
  --z-tooltip: 800;
}

/* Dark Theme Variant Overrides */
[data-theme="dark"] {
  --bg-app: #0B0F17;
  --bg-surface: #1E293B;
  --bg-surface-elevated: #334155;
  --bg-surface-hover: #2D3748;
  --border-color: #334155;
  --border-color-hover: #475569;
  
  --text-main: #F8FAFC;
  --text-muted: #CBD5E1;
  --text-disabled: #64748B;
  
  --color-primary-light: rgba(37, 99, 235, 0.2);
  --color-success-bg: rgba(22, 163, 74, 0.2);
  --color-warning-bg: rgba(245, 158, 11, 0.2);
  --color-danger-bg: rgba(220, 38, 38, 0.2);

  --focus-ring-color: rgba(59, 130, 246, 0.5);

  --glass-bg: rgba(30, 41, 59, 0.85);
  --glass-border: rgba(51, 65, 85, 0.8);

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -2px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.35), 0 4px 6px -4px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
}