:root {
  /* ==========================================================================
     Base CSS & Variables — ColorLab Pro Design System
     Senior UI/UX Strategy: Minimal, Professional, Developer-focused.
     ========================================================================== */

  /* 1. Brand & Identity Colors */
  --brand-primary: #111111;
  --brand-accent: #7C3AED;      /* Vibrant Purple */
  --brand-accent-soft: rgba(124, 58, 237, 0.1);
  --brand-blue: #2563EB;
  --brand-cyan: #06B6D4;
  --brand-pink: #DB2777;
  --brand-yellow: #EAB308;

  /* 2. Neutral Palette (Modern Layers & Borders) */
  --bg-main: #FFFFFF;
  --bg-muted: #F8FAFC;
  --bg-surface: #FFFFFF;
  --bg-card: #FFFFFF;
  --bg-interactive: #F1F5F9;

  /* Unified Border System */
  --border-width: 1px;
  --border-main: #E2E8F0;
  --border-subtle: rgba(0, 0, 0, 0.05);
  --border-hover: rgba(124, 58, 237, 0.2);
  --border-interactive: var(--brand-accent);
  --border-focus: rgba(124, 58, 237, 0.4);

  /* 3. Typography Colors */
  --text-main: #0F172A;
  --text-muted: #64748B;
  --text-light: #94A3B8;
  --text-inverse: #FFFFFF;

  /* 4. Typography Scale (Minor Third) */
  --text-hero: clamp(2.75rem, 6vw, 4.5rem);
  --text-h1: 2.5rem;
  --text-h2: 2rem;
  --text-h3: 1.5rem;
  --text-h4: 1.25rem;
  --text-base: 1rem;
  --text-sm: 0.875rem;
  --text-xs: 0.75rem;

  /* 5. 8px Grid Spacing System */
  --s-1: 4px;
  --s-2: 8px;
  --s-3: 12px;
  --s-4: 16px;
  --s-6: 24px;
  --s-8: 32px;
  --s-10: 40px;
  --s-12: 48px;
  --s-16: 64px;
  --s-20: 80px;

  /* 6. Border Radius system (Aligned with UI Spec) */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Shorthand Aliases */
  --r-sm: var(--radius-sm);
  --r-md: var(--radius-md);
  --r-lg: var(--radius-lg);
  --r-xl: var(--radius-xl);
  --r-full: var(--radius-full);

  /* 7. Elevation / Shadows (Premium Multi-layered) */
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.07), 0 4px 6px -2px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 10px 10px -5px rgba(0,0,0,0.04);
  --shadow-premium: 0 1px 1px rgba(0,0,0,0.05), 0 2px 2px rgba(0,0,0,0.05), 0 4px 4px rgba(0,0,0,0.05), 0 8px 8px rgba(0,0,0,0.05), 0 16px 16px rgba(0,0,0,0.05);

  /* 8. Animations & Transitions */
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --transition-base: 0.3s var(--ease-out-expo);
  --transition-relax: 0.5s var(--ease-out-expo);
  --transition-fast: 0.15s var(--ease-out-expo);

  /* Font Families */
  --font-primary: "Outfit", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-arabic: "Readex Pro", "Outfit", sans-serif;
}

/* Base Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  scrollbar-width: thin;
  scrollbar-color: var(--brand-primary) transparent;
}

::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--border-hover);
  border-radius: var(--r-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-light);
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Ensure all form elements and buttons inherit the design system fonts */
input, 
button, 
select, 
textarea,
optgroup {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
}

[lang="ar"] body,
[dir="rtl"] body {
  font-family: var(--font-arabic);
}

/* Typography Scale Implementation */
h1 { font-size: var(--text-h1); }
h2 { font-size: var(--text-h2); }
h3 { font-size: var(--text-h3); }
h4 { font-size: var(--text-h4); }

h1, h2, h3, h4 {
  line-height: 1.2;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.03em;
}

[lang="ar"] h1,
[lang="ar"] h2,
[lang="ar"] h3,
[lang="ar"] h4 {
  letter-spacing: 0;
  line-height: 1.4;
}

a {
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-text-muted);
}

ul {
  list-style: none;
}

/* Generic Utility Classes — Using logical properties where possible */
.text-center {
  text-align: center;
}
.text-left {
  text-align: left;
}
.text-right {
  text-align: right;
}

.text-muted {
  color: var(--color-text-muted);
}
.text-sm {
  font-size: 0.875rem;
}

/* Backgrounds */
.bg-primary {
  background-color: var(--color-bg);
}
.bg-alt {
  background-color: var(--color-bg-alt);
}

/* Spacing Helpers (8px Grid) */
.mt-1 { margin-top: var(--s-1); }
.mt-2 { margin-top: var(--s-2); }
.mt-4 { margin-top: var(--s-4); }
.mt-6 { margin-top: var(--s-6); }
.mt-8 { margin-top: var(--s-8); }
.mt-12 { margin-top: var(--s-12); }
.mt-16 { margin-top: var(--s-16); }

.mb-1 { margin-bottom: var(--s-1); }
.mb-2 { margin-bottom: var(--s-2); }
.mb-4 { margin-bottom: var(--s-4); }
.mb-6 { margin-bottom: var(--s-6); }
.mb-8 { margin-bottom: var(--s-8); }

.p-4 { padding: var(--s-4); }
.p-6 { padding: var(--s-6); }
.p-8 { padding: var(--s-8); }

.px-4 { padding-left: var(--s-4); padding-right: var(--s-4); }
.px-6 { padding-left: var(--s-6); padding-right: var(--s-6); }

.py-12 { padding-top: var(--s-12); padding-bottom: var(--s-12); }
.py-16 { padding-top: var(--s-16); padding-bottom: var(--s-16); }

/* Display Helpers */
.w-100 {
  width: 100%;
}
.w-80 {
  width: 80%;
}
.w-60 {
  width: 60%;
}

/* Fade in Animation */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in {
  animation: fadeIn 0.4s ease forwards;
}

[dir="rtl"] .rtl-flip {
  transform: scaleX(-1);
}