/* 🎨 Modern Design System Implementation
   Based on UI_UX_ENHANCEMENT_PLAN.md specifications
   Mobile-first, accessible, modern component library
*/

/* ===================================
   DESIGN TOKENS & CSS VARIABLES
   ================================ */

:root {
  /* 
     MODERN CHARITY PALETTE (Proposal: Compassionate Modernity)
     Primary: Deep Blue for trust, stability
     Action: Gold/Star for high-priority actions
     Success: Emerald for positive reinforcement
  */

  /* Primary Brand Colors - Deep Blue Scale */
  --color-primary-50: #EFF6FF;
  --color-primary-100: #DBEAFE;
  --color-primary-200: #BFDBFE;
  --color-primary-300: #93C5FD;
  --color-primary-400: #60A5FA;
  --color-primary-500: #3B82F6;
  /* Standard Blue */
  --color-primary-600: #2563EB;
  --color-primary-700: #1D4ED8;
  /* New Primary Base */
  --color-primary-800: #1E40AF;
  --color-primary-900: #1E3A8A;
  /* Deep Anchor */

  /* Usage Aliases */
  --color-primary: var(--color-primary-700);
  --color-primary-light: var(--color-primary-400);
  --color-primary-dark: var(--color-primary-900);

  /* Action / Accent Color - Gold */
  --color-action: #F59E0B;
  --color-action-hover: #D97706;
  --color-action-light: #FCD34D;

  /* Success & Status Colors */
  --color-success: #10B981;
  --color-success-light: #34D399;
  --color-success-dark: #047857;
  --color-warning: #F59E0B;
  --color-warning-light: #FBBF24;
  --color-warning-dark: #D97706;
  --color-error: #EF4444;
  --color-error-light: #F87171;
  --color-error-dark: #DC2626;

  /* Neutral Colors */
  --color-gray-50: #F9FAFB;
  --color-gray-100: #F3F4F6;
  --color-gray-200: #E5E7EB;
  --color-gray-300: #D1D5DB;
  --color-gray-400: #9CA3AF;
  --color-gray-500: #6B7280;
  --color-gray-600: #4B5563;
  --color-gray-700: #374151;
  --color-gray-800: #1F2937;
  --color-gray-900: #111827;

  /* Gradient Presets */
  --gradient-primary: linear-gradient(135deg, var(--color-primary-900) 0%, var(--color-primary-600) 100%);
  --gradient-action: linear-gradient(135deg, #F59E0B 0%, #D97706 100%);
  --gradient-glass: linear-gradient(145deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
  --gradient-overlay: linear-gradient(to bottom, rgba(30, 58, 138, 0.4), rgba(30, 58, 138, 0.9));

  /* Typography Scale */
  --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-family-heading: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --font-size-xs: 0.75rem;
  /* 12px */
  --font-size-sm: 0.875rem;
  /* 14px */
  --font-size-base: 1rem;
  /* 16px */
  --font-size-lg: 1.125rem;
  /* 18px */
  --font-size-xl: 1.25rem;
  /* 20px */
  --font-size-2xl: 1.5rem;
  /* 24px */
  --font-size-3xl: 1.875rem;
  /* 30px */
  --font-size-4xl: 2.25rem;
  /* 36px */
  --font-size-5xl: 3rem;
  /* 48px */
  --font-size-hero: clamp(3rem, 5vw, 4.5rem);

  /* Font Weights */
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;

  /* Spacing Scale */
  --space-xs: 0.25rem;
  /* 4px */
  --space-sm: 0.5rem;
  /* 8px */
  --space-md: 1rem;
  /* 16px */
  --space-lg: 1.5rem;
  /* 24px */
  --space-xl: 2rem;
  /* 32px */
  --space-2xl: 3rem;
  /* 48px */
  --space-3xl: 4rem;
  /* 64px */
  --space-4xl: 6rem;
  /* 96px */

  /* Border Radius */
  --radius-sm: 0.25rem;
  /* 4px */
  --radius-md: 0.375rem;
  /* 6px */
  --radius-lg: 0.5rem;
  /* 8px */
  --radius-xl: 0.75rem;
  /* 12px */
  --radius-2xl: 1rem;
  /* 16px */
  --radius-full: 9999px;

  /* 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-glow: 0 0 15px rgba(59, 130, 246, 0.5);

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-base: 200ms ease-in-out;
  --transition-slow: 300ms ease-in-out;

  /* Glassmorphism */
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-bg-dark: rgba(17, 24, 39, 0.7);
  --glass-border: 1px solid rgba(255, 255, 255, 0.2);
  --glass-blur: blur(12px);

  /* Z-index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  --z-toast: 1080;
}

/* ===================================
   MODERN RESET & BASE STYLES
   ================================ */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  line-height: 1.15;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-primary);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-gray-900);
  background-color: var(--color-gray-50);
  margin: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===================================
   MODERN BUTTON SYSTEM
   ================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  font-family: var(--font-family-primary);
  font-weight: var(--font-weight-medium);
  font-size: var(--font-size-sm);
  line-height: 1.5;
  text-decoration: none;
  border: 2px solid transparent;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
  user-select: none;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

/* Primary Button */
.btn--primary {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

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

.btn--primary:active {
  transform: translateY(0);
  box-shadow: var(--shadow-md);
}

/* Secondary Button */
.btn--secondary {
  background-color: var(--color-gray-100);
  color: var(--color-gray-900);
  border-color: var(--color-gray-300);
}

.btn--secondary:hover {
  background-color: var(--color-gray-200);
  border-color: var(--color-gray-400);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Outline Button */
.btn--outline {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

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

/* Ghost Button */
.btn--ghost {
  background-color: transparent;
  color: var(--color-gray-700);
  border-color: transparent;
}

.btn--ghost:hover {
  background-color: var(--color-gray-100);
  color: var(--color-gray-900);
}

/* Success Button */
.btn--success {
  background-color: var(--color-success);
  color: white;
  border-color: var(--color-success);
}

.btn--success:hover {
  background-color: var(--color-success-dark);
  border-color: var(--color-success-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}

/* Button Sizes */
.btn--sm {
  padding: var(--space-xs) var(--space-md);
  font-size: var(--font-size-xs);
}

.btn--lg {
  padding: var(--space-lg) var(--space-2xl);
  font-size: var(--font-size-lg);
}

.btn--full {
  width: 100%;
}

/* Loading State */
.btn--loading {
  color: transparent;
  pointer-events: none;
}

.btn--loading::after {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  top: 50%;
  left: 50%;
  margin-left: -8px;
  margin-top: -8px;
  border: 2px solid transparent;
  border-top-color: currentColor;
  border-radius: 50%;
  animation: btn-loading-spin 1s ease infinite;
}

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

/* ===================================
   MODERN CARD COMPONENT
   ================================ */

.card {
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
  transition: all var(--transition-base);
  overflow: hidden;
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.card__header {
  padding: var(--space-lg);
  border-bottom: 1px solid var(--color-gray-200);
}

.card__title {
  margin: 0;
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
}

.card__content {
  padding: var(--space-lg);
}

.card__footer {
  padding: var(--space-lg);
  background-color: var(--color-gray-50);
  border-top: 1px solid var(--color-gray-200);
}

/* ===================================
   CAUSE CARD COMPONENT
   ================================ */

.cause-card {
  background: white;
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
}

.cause-card:hover {
  box-shadow: var(--shadow-xl);
  transform: translateY(-4px);
}

.cause-card__image {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
}

.cause-card__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.cause-card:hover .cause-card__image img {
  transform: scale(1.05);
}

.cause-card__badge {
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  background: var(--color-error);
  color: white;
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-full);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.cause-card__content {
  padding: var(--space-lg);
}

.cause-card__title {
  margin: 0 0 var(--space-md) 0;
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-semibold);
  color: var(--color-gray-900);
  line-height: 1.4;
}

.cause-card__excerpt {
  margin: 0 0 var(--space-lg) 0;
  color: var(--color-gray-600);
  line-height: 1.6;
}

.cause-card__stats {
  display: flex;
  justify-content: space-between;
  margin-top: var(--space-lg);
  padding-top: var(--space-md);
  border-top: 1px solid var(--color-gray-200);
}

.stat {
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
  font-weight: var(--font-weight-medium);
}

/* ===================================
   PROGRESS BAR COMPONENT
   ================================ */

.progress-bar {
  position: relative;
  width: 100%;
  height: 8px;
  background-color: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin: var(--space-md) 0;
}

.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  border-radius: var(--radius-full);
  transition: width var(--transition-slow) ease-out;
  position: relative;
}

.progress-bar__fill::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 20px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  animation: progress-shine 2s infinite;
}

@keyframes progress-shine {
  0% {
    transform: translateX(-20px);
  }

  100% {
    transform: translateX(100px);
  }
}

.progress-bar__label {
  display: flex;
  justify-content: space-between;
  margin-top: var(--space-sm);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-700);
}

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

/* Mobile First Approach */
@media (min-width: 640px) {
  .cause-card__content {
    padding: var(--space-xl);
  }

  .btn--lg {
    padding: var(--space-xl) var(--space-3xl);
  }
}

@media (min-width: 768px) {
  .cause-card__title {
    font-size: var(--font-size-2xl);
  }
}

@media (min-width: 1024px) {
  .cause-card:hover {
    transform: translateY(-6px);
  }
}

/* ===================================
   NEW UTILITIES (Phase 1)
   ================================ */

/* Glassmorphism Utilities */
.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  /* Safari support */
  border: var(--glass-border);
  box-shadow: var(--shadow-lg);
}

.glass-panel-dark {
  background: var(--glass-bg-dark);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: white;
}

/* Gradient Utilities */
.bg-gradient-primary {
  background: var(--gradient-primary);
  color: white;
}

.bg-gradient-action {
  background: var(--gradient-action);
  color: white;
}

.bg-gradient-glass {
  background: var(--gradient-glass);
}

.text-gradient {
  background: linear-gradient(135deg, var(--color-primary-400), var(--color-success-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.text-gradient-gold {
  background: linear-gradient(135deg, #FCD34D, #F59E0B);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Modern Text Utilities */
.text-hero {
  font-family: var(--font-family-heading);
  font-size: var(--font-size-hero);
  font-weight: var(--font-weight-extrabold);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.text-display {
  font-family: var(--font-family-heading);
  font-weight: var(--font-weight-bold);
  letter-spacing: -0.01em;
}

/* Animation Utilities */
.hover-lift {
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.hover-lift:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.hover-glow:hover {
  box-shadow: var(--shadow-glow);
}