/* ============================================
   ETC AdBlue — Design Tokens
   CSS Custom Properties (Variables)
   ============================================ */

:root {
  /* ── Primary Colors ── */
  --color-primary: #0052CC;
  --color-primary-dark: #003D99;
  --color-primary-darker: #002E73;
  --color-primary-light: #3378DB;
  --color-primary-lighter: #E6F0FF;
  --color-primary-ghost: rgba(0, 82, 204, 0.08);

  /* ── Navy / Dark ── */
  --color-navy: #0A1628;
  --color-navy-light: #142240;
  --color-navy-mid: #1B2D4F;

  /* ── Accent ── */
  --color-accent: #00B4D8;
  --color-accent-dark: #0096B4;
  --color-accent-light: #48CAE4;
  --color-accent-ghost: rgba(0, 180, 216, 0.1);

  /* ── Neutral ── */
  --color-white: #FFFFFF;
  --color-gray-50: #F8FAFC;
  --color-gray-100: #F1F5F9;
  --color-gray-200: #E2E8F0;
  --color-gray-300: #CBD5E1;
  --color-gray-400: #94A3B8;
  --color-gray-500: #64748B;
  --color-gray-600: #475569;
  --color-gray-700: #334155;
  --color-gray-800: #1E293B;
  --color-gray-900: #0F172A;

  /* ── Semantic ── */
  --color-success: #10B981;
  --color-success-light: #D1FAE5;
  --color-warning: #F59E0B;
  --color-warning-light: #FEF3C7;
  --color-danger: #EF4444;
  --color-danger-light: #FEE2E2;
  --color-info: #3B82F6;
  --color-info-light: #DBEAFE;

  /* ── Typography ── */
  --font-heading: 'Montserrat', sans-serif;
  --font-body: 'Roboto', sans-serif;

  --fw-regular: 400;
  --fw-medium: 500;
  --fw-semibold: 600;
  --fw-bold: 700;

  --fs-xs: 0.75rem;     /* 12px */
  --fs-sm: 0.875rem;    /* 14px */
  --fs-base: 1rem;      /* 16px */
  --fs-md: 1.125rem;    /* 18px */
  --fs-lg: 1.25rem;     /* 20px */
  --fs-xl: 1.375rem;    /* 22px */
  --fs-2xl: 1.75rem;    /* 28px */
  --fs-3xl: 2.25rem;    /* 36px */
  --fs-4xl: 2.5rem;     /* 40px */
  --fs-5xl: 3.5rem;     /* 56px */
  --fs-6xl: 4rem;       /* 64px */

  --lh-tight: 1.2;
  --lh-snug: 1.3;
  --lh-normal: 1.5;
  --lh-relaxed: 1.65;
  --lh-loose: 1.8;

  --ls-tight: -0.02em;
  --ls-normal: 0;
  --ls-wide: 0.02em;
  --ls-wider: 0.05em;
  --ls-widest: 0.1em;

  /* ── Spacing (4px base) ── */
  --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-14: 3.5rem;   /* 56px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  --space-24: 6rem;     /* 96px */
  --space-32: 8rem;     /* 128px */

  /* ── Border Radius ── */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-2xl: 24px;
  --radius-full: 9999px;

  /* ── Shadows ── */
  --shadow-xs: 0 1px 2px rgba(10, 22, 40, 0.04);
  --shadow-sm: 0 2px 4px rgba(10, 22, 40, 0.06);
  --shadow-md: 0 4px 12px rgba(10, 22, 40, 0.08);
  --shadow-lg: 0 8px 24px rgba(10, 22, 40, 0.1);
  --shadow-xl: 0 16px 48px rgba(10, 22, 40, 0.12);
  --shadow-2xl: 0 24px 64px rgba(10, 22, 40, 0.16);
  --shadow-inner: inset 0 2px 4px rgba(10, 22, 40, 0.06);
  --shadow-primary: 0 4px 16px rgba(0, 82, 204, 0.3);
  --shadow-card-hover: 0 12px 32px rgba(10, 22, 40, 0.14);

  /* ── Transitions ── */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);

  --duration-fast: 150ms;
  --duration-base: 250ms;
  --duration-slow: 400ms;
  --duration-slower: 600ms;

  --transition-colors: color var(--duration-base) var(--ease-out),
                        background-color var(--duration-base) var(--ease-out),
                        border-color var(--duration-base) var(--ease-out);
  --transition-transform: transform var(--duration-base) var(--ease-out);
  --transition-shadow: box-shadow var(--duration-base) var(--ease-out);
  --transition-all: all var(--duration-base) var(--ease-out);

  /* ── Z-Index Scale ── */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-overlay: 300;
  --z-modal: 400;
  --z-toast: 500;

  /* ── Layout ── */
  --container-max: 1280px;
  --container-narrow: 960px;
  --container-wide: 1440px;
  --container-padding: var(--space-6);

  --header-height: 80px;
  --header-height-scrolled: 64px;

  /* ── Glassmorphism ── */
  --glass-bg: rgba(255, 255, 255, 0.85);
  --glass-bg-dark: rgba(10, 22, 40, 0.8);
  --glass-blur: 16px;
  --glass-border: rgba(255, 255, 255, 0.2);
}

/* ── Dark mode adjustments (for future) ── */
@media (prefers-color-scheme: dark) {
  :root {
    /* Reserved for future dark mode tokens */
  }
}