/*
 * Modern Design System - Mobile First
 * Created: 2026-02-06
 * 
 * Features:
 * - CSS Variables (Light + Dark Mode)
 * - Glassmorphism Effects
 * - Mobile-First Responsive
 * - Touch-Optimized (44x44px minimum)
 * - Smooth Animations
 */

/* ========================================
   CSS VARIABLES - LIGHT MODE (DEFAULT)
   ======================================== */
:root {
  /* Primary Colors */
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-primary-light: #dbeafe;
  --color-primary-dark: #1e40af;
  
  /* Background */
  --color-bg-primary: #ffffff;
  --color-bg-secondary: #f8fafc;
  --color-bg-tertiary: #f1f5f9;
  
  /* Surface (Cards) */
  --color-surface: #ffffff;
  --color-surface-hover: #f8fafc;
  --color-surface-elevated: #ffffff;
  
  /* Text */
  --color-text-primary: #0f172a;
  --color-text-secondary: #475569;
  --color-text-tertiary: #94a3b8;
  --color-text-inverse: #ffffff;
  
  /* Border */
  --color-border: #e2e8f0;
  --color-border-hover: #cbd5e1;
  --color-border-light: #f1f5f9;
  
  /* Status Colors */
  --color-success: #10b981;
  --color-success-bg: #d1fae5;
  --color-error: #ef4444;
  --color-error-bg: #fee2e2;
  --color-warning: #f59e0b;
  --color-warning-bg: #fef3c7;
  --color-info: #3b82f6;
  --color-info-bg: #dbeafe;
  
  /* Glassmorphism */
  --glass-bg: rgba(255, 255, 255, 0.8);
  --glass-bg-light: rgba(255, 255, 255, 0.6);
  --glass-border: rgba(255, 255, 255, 0.2);
  --glass-shadow: rgba(0, 0, 0, 0.05);
  --glass-shadow-hover: rgba(0, 0, 0, 0.1);
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px rgba(0, 0, 0, 0.15);
  
  /* Spacing Scale */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-2xl: 24px;
  --radius-full: 9999px;
  
  /* 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);
  
  /* Z-Index Scale */
  --z-base: 0;
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 2040;
  --z-modal: 2050;
  --z-popover: 2060;
  --z-tooltip: 1070;
}

/* Dark mode removed - light only */

/* ========================================
   BASE RESET & SMOOTH TRANSITIONS
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

/* Smooth theme transitions */
*,
*::before,
*::after {
  transition-property: background-color, border-color, color, fill, stroke;
  transition-duration: var(--transition-base);
  transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ========================================
   TYPOGRAPHY
   ======================================== */
html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
}

/* Heading Styles */
.text-display {
  font-size: 2rem;
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.text-h1 {
  font-size: 1.75rem;
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.text-h2 {
  font-size: 1.5rem;
  line-height: 1.4;
  font-weight: 600;
}

.text-h3 {
  font-size: 1.25rem;
  line-height: 1.4;
  font-weight: 600;
}

.text-body {
  font-size: 1rem;
  line-height: 1.6;
  font-weight: 400;
}

.text-small {
  font-size: 0.875rem;
  line-height: 1.5;
}

.text-xs {
  font-size: 0.75rem;
  line-height: 1.4;
}

/* Text Colors */
.text-primary { color: var(--color-text-primary); }
.text-secondary { color: var(--color-text-secondary); }
.text-tertiary { color: var(--color-text-tertiary); }

/* ========================================
   GLASSMORPHISM COMPONENTS
   ======================================== */

/* Glass Card */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-base);
}

.glass-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-border-hover);
}

/* Glass Header */
.glass-header {
  background: linear-gradient(135deg, 
    rgba(37, 99, 235, 0.95) 0%,
    rgba(29, 78, 216, 0.98) 100%
  );
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  box-shadow: var(--shadow-lg);
}

/* Frosted Overlay */
.frosted-overlay {
  background: rgba(15, 23, 42, 0.4);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

/* ========================================
   BUTTONS - TOUCH OPTIMIZED
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  min-height: 44px;
  min-width: 44px;
  padding: 12px 24px;
  border: none;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: all var(--transition-fast);
  -webkit-user-select: none;
  user-select: none;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--color-surface);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-surface-hover);
  border-color: var(--color-border-hover);
}

.btn-glass {
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  color: var(--color-text-primary);
  border: 1px solid var(--glass-border);
}

.btn-glass:hover {
  background: var(--glass-bg-light);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Icon Button */
.btn-icon {
  min-width: 44px;
  min-height: 44px;
  width: 44px;
  height: 44px;
  padding: 0;
  border-radius: var(--radius-full);
}

/* ========================================
   CARDS - MOBILE OPTIMIZED
   ======================================== */

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  min-height: 80px;
  cursor: pointer;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary-light);
}

.card:active {
  transform: translateY(0);
}

/* Glass Card Variant */
.card-glass {
  background: var(--glass-bg);
  backdrop-filter: blur(16px) saturate(180%);
  -webkit-backdrop-filter: blur(16px) saturate(180%);
  border: 1px solid var(--glass-border);
}

/* ========================================
   BOTTOM NAVIGATION (Mobile)
   ======================================== */

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: var(--glass-bg);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-top: 1px solid var(--glass-border);
  padding: var(--space-sm) 0;
  padding-bottom: calc(var(--space-sm) + env(safe-area-inset-bottom));
  z-index: var(--z-fixed);
  box-shadow: 0 -4px 24px var(--glass-shadow);
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm);
  min-height: 56px;
  border: none;
  background: transparent;
  color: var(--color-text-secondary);
  font-size: 0.75rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: all var(--transition-fast);
  -webkit-tap-highlight-color: transparent;
}

.nav-item:active {
  transform: scale(0.95);
}

.nav-item.active {
  color: var(--color-primary);
}

.nav-item .icon {
  font-size: 1.5rem;
  transition: transform var(--transition-fast);
}

.nav-item.active .icon {
  transform: scale(1.1);
}

/* ========================================
   LOADING STATES
   ======================================== */

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--color-bg-secondary) 0%,
    var(--color-bg-tertiary) 50%,
    var(--color-bg-secondary) 100%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s ease-in-out infinite;
  border-radius: var(--radius-md);
}

@keyframes skeleton-loading {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* Shimmer Effect */
.shimmer {
  position: relative;
  overflow: hidden;
}

.shimmer::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  transform: translateX(-100%);
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.2),
    transparent
  );
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  100% { transform: translateX(100%); }
}

/* Spinner */
.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
}

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

/* Theme toggle removed - light only */

/* ========================================
   UTILITY CLASSES
   ======================================== */

/* Safe Areas */
.safe-area-top {
  padding-top: env(safe-area-inset-top);
}

.safe-area-bottom {
  padding-bottom: env(safe-area-inset-bottom);
}

.safe-area-left {
  padding-left: env(safe-area-inset-left);
}

.safe-area-right {
  padding-right: env(safe-area-inset-right);
}

/* Spacing */
.p-0 { padding: 0; }
.p-xs { padding: var(--space-xs); }
.p-sm { padding: var(--space-sm); }
.p-md { padding: var(--space-md); }
.p-lg { padding: var(--space-lg); }
.p-xl { padding: var(--space-xl); }

.m-0 { margin: 0; }
.m-xs { margin: var(--space-xs); }
.m-sm { margin: var(--space-sm); }
.m-md { margin: var(--space-md); }
.m-lg { margin: var(--space-lg); }
.m-xl { margin: var(--space-xl); }

/* Flex */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

/* Grid */
.grid { display: grid; }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

/* Shadows */
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }

/* Border Radius */
.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

/* ========================================
   RESPONSIVE BREAKPOINTS
   ======================================== */

/* Small tablets (≥ 640px) */
@media (min-width: 640px) {
  .text-display { font-size: 2.5rem; }
  .text-h1 { font-size: 2rem; }
  .text-h2 { font-size: 1.75rem; }
  
  .bottom-nav {
    display: none; /* Hide on desktop */
  }
}

/* Tablets (≥ 768px) */
@media (min-width: 768px) {
  .container {
    max-width: 768px;
    margin: 0 auto;
  }
  
  .grid-md-2 { grid-template-columns: repeat(2, 1fr); }
}

/* Desktop (≥ 1024px) */
@media (min-width: 1024px) {
  .container {
    max-width: 1024px;
  }
  
  .grid-lg-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-lg-4 { grid-template-columns: repeat(4, 1fr); }
}

/* Large Desktop (≥ 1280px) */
@media (min-width: 1280px) {
  .container {
    max-width: 1280px;
  }
}