/**
 * DESIGN SYSTEM - Premium Mobile-First
 * Inspired by Apple iOS & modern premium apps
 */

:root {
  /* ============================================
     TYPOGRAPHY
     ============================================ */
  --font-primary: -apple-system, BlinkMacSystemFont, "SF Pro Display",
                  "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", Monaco, "Cascadia Code", "Consolas", monospace;

  /* Font sizes - Mobile first */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-base: 1rem;     /* 16px */
  --text-lg: 1.125rem;   /* 18px */
  --text-xl: 1.25rem;    /* 20px */
  --text-2xl: 1.5rem;    /* 24px */
  --text-3xl: 1.875rem;  /* 30px */
  --text-4xl: 2.25rem;   /* 36px */

  /* Font weights */
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;

  /* Line heights */
  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.75;

  /* ============================================
     COLORS - Dark Premium (Indigo Accent)
     ============================================ */

  /* Backgrounds - noir casse / anthracite */
  --bg-primary: #141416;
  --bg-secondary: #1C1C1F;
  --bg-tertiary: #252528;
  --bg-card: #1E1E21;
  --bg-input: #28282C;
  --bg-hover: #2A2A2E;

  /* Text - blanc casse, jamais pur */
  --text-primary: #E8E8ED;
  --text-secondary: #8E8E93;
  --text-tertiary: #636366;
  --text-disabled: #48484A;

  /* Accent unique - Indigo */
  --accent-primary: #6366F1;
  --accent-hover: #4F46E5;
  --accent-light: #818CF8;
  --accent-glow: rgba(99, 102, 241, 0.15);
  --accent-glow-strong: rgba(99, 102, 241, 0.25);

  /* Borders */
  --border-primary: rgba(255, 255, 255, 0.06);
  --border-secondary: rgba(255, 255, 255, 0.10);
  --border-card: rgba(255, 255, 255, 0.08);
  --border-accent: rgba(99, 102, 241, 0.3);

  /* Functional (minimal usage) */
  --color-success: #34D399;
  --color-error: #F87171;
  --color-warning: #FBBF24;

  /* ============================================
     SPACING
     ============================================ */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.25rem;   /* 20px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-10: 2.5rem;   /* 40px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */

  /* ============================================
     BORDER RADIUS
     ============================================ */
  --radius-sm: 0.375rem;  /* 6px */
  --radius-md: 0.5rem;    /* 8px */
  --radius-lg: 0.75rem;   /* 12px */
  --radius-xl: 1rem;      /* 16px */
  --radius-2xl: 1.5rem;   /* 24px */
  --radius-full: 9999px;

  /* ============================================
     SHADOWS - Dark mode (very light)
     ============================================ */
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.2);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-xl: 0 16px 40px rgba(0, 0, 0, 0.4);
  --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.25);
  --shadow-float: 0 8px 32px rgba(0, 0, 0, 0.4);

  /* ============================================
     TRANSITIONS
     ============================================ */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Spring animations */
  --spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);

  /* ============================================
     Z-INDEX LAYERS
     ============================================ */
  --z-base: 0;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal-backdrop: 400;
  --z-modal: 500;
  --z-popover: 600;
  --z-tooltip: 700;
  --z-fab: 800;

  /* ============================================
     LAYOUT
     ============================================ */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;

  --header-height: 56px;
  --header-height-desktop: 64px;

  /* ============================================
     SAFE AREAS (iOS)
     ============================================ */
  --safe-area-inset-top: env(safe-area-inset-top);
  --safe-area-inset-bottom: env(safe-area-inset-bottom);
  --safe-area-inset-left: env(safe-area-inset-left);
  --safe-area-inset-right: env(safe-area-inset-right);
}

/* ============================================
   LIGHT THEME OVERRIDE
   ============================================ */
[data-theme="light"] {
  --bg-primary: #FFFFFF;
  --bg-secondary: #F5F5F7;
  --bg-tertiary: #E8E8ED;
  --bg-card: #FFFFFF;
  --bg-input: #F0F0F5;
  --bg-hover: #E8E8ED;

  --text-primary: #1D1D1F;
  --text-secondary: #6E6E73;
  --text-tertiary: #98989D;
  --text-disabled: #C7C7CC;

  --accent-primary: #6366F1;
  --accent-hover: #4F46E5;
  --accent-light: #4F46E5;
  --accent-glow: rgba(99, 102, 241, 0.1);
  --accent-glow-strong: rgba(99, 102, 241, 0.18);

  --border-primary: rgba(0, 0, 0, 0.08);
  --border-secondary: rgba(0, 0, 0, 0.12);
  --border-card: rgba(0, 0, 0, 0.08);
  --border-accent: rgba(99, 102, 241, 0.25);

  --color-success: #16A34A;
  --color-error: #DC2626;
  --color-warning: #D97706;

  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-float: 0 8px 32px rgba(0, 0, 0, 0.1);
}

/* ============================================
   BASE STYLES
   ============================================ */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-primary);
  font-weight: var(--font-normal);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  overflow-x: hidden;
}

/* ============================================
   RESPONSIVE BREAKPOINTS
   ============================================ */
@media (min-width: 640px) {
  :root {
    --text-3xl: 2rem;     /* 32px */
    --text-4xl: 2.5rem;   /* 40px */
  }
}

@media (min-width: 1024px) {
  :root {
    --text-4xl: 3rem;     /* 48px */
  }
}