/* ===== CSS VARIABLES ===== */
:root {
  /* Colors */
  --primary-50: #f0f9ff;
  --primary-100: #e0f2fe;
  --primary-500: #0ea5e9;
  --primary-600: #0284c7;
  --primary-700: #0369a1;
  --primary-900: #0c4a6e;
  
  --secondary-50: #fdf4ff;
  --secondary-100: #fae8ff;
  --secondary-500: #a855f7;
  --secondary-600: #9333ea;
  --secondary-700: #7c3aed;
  --secondary-900: #581c87;
  
  --success-50: #f0fdf4;
  --success-500: #22c55e;
  --success-600: #16a34a;
  --success-700: #15803d;
  
  --warning-50: #fffbeb;
  --warning-500: #f59e0b;
  --warning-600: #d97706;
  --warning-700: #b45309;
  
  --error-50: #fef2f2;
  --error-500: #ef4444;
  --error-600: #dc2626;
  --error-700: #b91c1c;
  
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  
  /* Dark theme colors */
  --dark-bg-primary: #0f172a;
  --dark-bg-secondary: #1e293b;
  --dark-bg-tertiary: #334155;
  --dark-text-primary: #f8fafc;
  --dark-text-secondary: #cbd5e1;
  --dark-text-muted: #94a3b8;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--primary-500), var(--secondary-500));
  --gradient-secondary: linear-gradient(135deg, var(--secondary-500), var(--primary-500));
  --gradient-success: linear-gradient(135deg, var(--success-500), var(--success-600));
  --gradient-warning: linear-gradient(135deg, var(--warning-500), var(--warning-600));
  --gradient-error: linear-gradient(135deg, var(--error-500), var(--error-600));
  --gradient-dark: linear-gradient(135deg, var(--dark-bg-primary), var(--dark-bg-secondary));
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
  
  /* Spacing */
  --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;
  
  /* Border radius */
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;
  --radius-2xl: 1rem;
  --radius-3xl: 1.5rem;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
  
  /* Typography */
  --font-family-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-family-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
  
  /* Font sizes */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  
  /* Line heights */
  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;
  
  /* Z-index */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* ===== RESET & BASE STYLES ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -ms-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--dark-text-primary);
  background: var(--gradient-dark);
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: var(--leading-tight);
  margin-bottom: var(--space-4);
}

h1 {
  font-size: var(--text-4xl);
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-align: center;
  margin-bottom: var(--space-8);
}

h2 {
  font-size: var(--text-2xl);
  color: var(--dark-text-primary);
}

h3 {
  font-size: var(--text-xl);
  color: var(--dark-text-secondary);
}

p {
  margin-bottom: var(--space-4);
  color: var(--dark-text-secondary);
}

/* ===== LAYOUT ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-6);
  width: 100%;
}

.main-content {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-8) var(--space-4);
}

/* ===== UTILITIES ===== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.hidden {
  display: none !important;
}

.fade-in {
  animation: fadeIn 0.5s ease-out forwards;
}

.fade-out {
  animation: fadeOut 0.3s ease-in forwards;
}

.slide-in-up {
  animation: slideInUp 0.4s ease-out forwards;
}

.slide-out-down {
  animation: slideOutDown 0.3s ease-in forwards;
}

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

@keyframes fadeOut {
  from {
    opacity: 1;
    transform: translateY(0);
  }
  to {
    opacity: 0;
    transform: translateY(-10px);
  }
}

@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideOutDown {
  from {
    opacity: 1;
    transform: translateY(0);
  }
  to {
    opacity: 0;
    transform: translateY(20px);
  }
}

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
}

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-10px);
  }
}

/* ===== FOCUS STYLES ===== */
:focus {
  outline: 2px solid var(--primary-500);
  outline-offset: 2px;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* ===== SELECTION STYLES ===== */
::selection {
  background-color: var(--primary-500);
  color: white;
}

::-moz-selection {
  background-color: var(--primary-500);
  color: white;
}