/* CSS Reset and Base Variables */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* Color palette - White theme with gold accents */
  --color-background: #ffffff;
  --color-gold: #FFD700;
  --color-gold-light: #FFECB3;
  --color-gold-dark: #FFC107;
  --color-text: #333333;
  --color-text-light: #666666;
  --color-overlay: rgba(0, 0, 0, 0.8);
  
  /* Typography */
  --font-primary: 'Playfair Display', Georgia, serif;
  --font-decorative: 'Great Vibes', cursive;
  
  /* Spacing */
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-medium: 0.3s ease;
}

html, body {
  height: 100%;
}

body {
  font-family: var(--font-primary);
  background-color: var(--color-background);
  color: var(--color-text);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Confetti Canvas */
#confetti-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1000;
}

/* Celebration View Container */
.celebration-view {
  min-height: 100vh;
  background-color: var(--color-background);
  padding: var(--spacing-lg);
  position: relative;
}

/* Birthday Header */
.birthday-header {
  text-align: center;
  padding: var(--spacing-xl) var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.birthday-message {
  font-family: var(--font-decorative);
  font-size: clamp(3rem, 10vw, 6rem);
  color: var(--color-gold-dark);
  text-shadow: 2px 2px 4px rgba(255, 215, 0, 0.3);
  animation: fadeInDown 1s ease-out;
  margin-bottom: var(--spacing-sm);
}

.birthday-subtitle {
  font-family: var(--font-primary);
  font-size: clamp(1rem, 3vw, 1.5rem);
  color: var(--color-text-light);
  font-style: italic;
  animation: fadeInUp 1s ease-out 0.3s both;
}

/* Gold decorative border */
.birthday-header::after {
  content: '✨ 🎂 ✨';
  display: block;
  font-size: 1.5rem;
  margin-top: var(--spacing-md);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.8; transform: scale(1.1); }
}

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

/* Fade in animation */
@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Memory Gallery Grid */
.memory-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: var(--spacing-md);
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md);
}

/* Gallery Item */
.gallery-item {
  position: relative;
  aspect-ratio: 1;
  border-radius: 12px;
  overflow: hidden;
  cursor: pointer;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  border: 3px solid transparent;
  transition: transform var(--transition-medium), 
              box-shadow var(--transition-medium),
              border-color var(--transition-medium);
}

.gallery-item:hover {
  transform: translateY(-5px) scale(1.02);
  box-shadow: 0 8px 25px rgba(255, 215, 0, 0.3);
  border-color: var(--color-gold);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-medium);
}

.gallery-item:hover img {
  transform: scale(1.05);
}

/* Video play icon overlay */
.play-icon {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 60px;
  height: 60px;
  background: rgba(255, 215, 0, 0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: white;
  pointer-events: none;
  transition: transform var(--transition-fast);
}

.gallery-item:hover .play-icon {
  transform: translate(-50%, -50%) scale(1.1);
}

/* Empty gallery message */
.empty-message {
  grid-column: 1 / -1;
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-light);
  font-style: italic;
}

/* Responsive adjustments */
@media (max-width: 768px) {
  .memory-gallery {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: var(--spacing-sm);
  }
  
  .celebration-view {
    padding: var(--spacing-md);
  }
  
  .birthday-header {
    padding: var(--spacing-lg) var(--spacing-sm);
  }
}

@media (max-width: 480px) {
  .memory-gallery {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .play-icon {
    width: 40px;
    height: 40px;
    font-size: 1rem;
  }
}

/* Modal/Lightbox Overlay */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--color-overlay);
  backdrop-filter: blur(5px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-medium), visibility var(--transition-medium);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

/* Modal Content Container */
.modal-content {
  position: relative;
  max-width: 90vw;
  max-height: 90vh;
  background: var(--color-background);
  border-radius: 16px;
  padding: var(--spacing-md);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-medium);
  overflow: hidden;
}

.modal-overlay.active .modal-content {
  transform: scale(1) translateY(0);
}

/* Close Button */
.modal-close {
  position: absolute;
  top: var(--spacing-sm);
  right: var(--spacing-sm);
  width: 40px;
  height: 40px;
  border: none;
  background: var(--color-gold);
  color: white;
  font-size: 1.5rem;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition-fast), transform var(--transition-fast);
  z-index: 10;
}

.modal-close:hover {
  background: var(--color-gold-dark);
  transform: scale(1.1);
}

/* Modal Media Container */
.modal-media {
  display: flex;
  align-items: center;
  justify-content: center;
  max-height: 70vh;
  overflow: hidden;
  border-radius: 8px;
}

.modal-media img {
  max-width: 100%;
  max-height: 70vh;
  object-fit: contain;
  border-radius: 8px;
}

.modal-media video {
  max-width: 100%;
  max-height: 70vh;
  border-radius: 8px;
}

/* Modal Caption */
.modal-caption {
  text-align: center;
  padding: var(--spacing-md) var(--spacing-sm);
  font-size: 1.1rem;
  color: var(--color-text);
  font-style: italic;
  border-top: 2px solid var(--color-gold-light);
  margin-top: var(--spacing-md);
}

/* Responsive modal */
@media (max-width: 768px) {
  .modal-content {
    max-width: 95vw;
    padding: var(--spacing-sm);
  }
  
  .modal-caption {
    font-size: 1rem;
    padding: var(--spacing-sm);
  }
  
  .modal-close {
    width: 35px;
    height: 35px;
    font-size: 1.2rem;
  }
}

/* Music Control Button */
.music-control {
  position: fixed;
  bottom: var(--spacing-lg);
  right: var(--spacing-lg);
  width: 60px;
  height: 60px;
  border: none;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-gold), var(--color-gold-dark));
  color: white;
  font-size: 1.5rem;
  cursor: pointer;
  box-shadow: 0 4px 15px rgba(255, 215, 0, 0.4);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
  z-index: 1500;
}

.music-control:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 20px rgba(255, 215, 0, 0.5);
}

.music-control.playing {
  animation: musicPulse 1s ease-in-out infinite;
}

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

@media (max-width: 480px) {
  .music-control {
    width: 50px;
    height: 50px;
    font-size: 1.2rem;
    bottom: var(--spacing-md);
    right: var(--spacing-md);
  }
}

/* Letter Mode Styles */
.letter-mode {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--color-background);
  z-index: 3000;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-lg);
}

.letter-mode.hidden {
  display: none;
}

.letter-close {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  width: 50px;
  height: 50px;
  border: none;
  background: var(--color-gold);
  color: white;
  font-size: 1.5rem;
  border-radius: 50%;
  cursor: pointer;
  transition: transform var(--transition-fast), background var(--transition-fast);
  z-index: 10;
}

.letter-close:hover {
  background: var(--color-gold-dark);
  transform: scale(1.1);
}

.letter-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xl);
  max-width: 1200px;
  width: 100%;
  flex: 1;
}

.letter-media {
  flex: 1;
  max-width: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.letter-media img,
.letter-media video {
  max-width: 100%;
  max-height: 70vh;
  border-radius: 12px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
  object-fit: contain;
}

.letter-content {
  flex: 1;
  max-width: 45%;
  padding: var(--spacing-lg);
}

.letter-text {
  font-family: var(--font-primary);
  font-size: clamp(1.1rem, 2.5vw, 1.4rem);
  line-height: 1.9;
  color: var(--color-text);
  white-space: pre-line;
}

.letter-nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  padding: var(--spacing-md);
}

.letter-nav-btn {
  width: 50px;
  height: 50px;
  border: 2px solid var(--color-gold);
  background: transparent;
  color: var(--color-gold-dark);
  font-size: 1.5rem;
  border-radius: 50%;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.letter-nav-btn:hover {
  background: var(--color-gold);
  color: white;
}

.letter-nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.letter-progress {
  font-family: var(--font-primary);
  font-size: 1rem;
  color: var(--color-text-light);
}

.hidden {
  display: none !important;
}

/* Responsive Letter Mode */
@media (max-width: 768px) {
  .letter-container {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .letter-media,
  .letter-content {
    max-width: 100%;
  }
  
  .letter-media img,
  .letter-media video {
    max-height: 40vh;
  }
  
  .letter-content {
    padding: var(--spacing-md);
    max-height: 35vh;
    overflow-y: auto;
  }
  
  .letter-text {
    font-size: 1rem;
  }
}

/* Modal Letter Text */
.modal-letter {
  text-align: center;
  padding: var(--spacing-md);
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.8;
  max-width: 600px;
  margin: 0 auto;
  background: linear-gradient(135deg, var(--color-gold-light) 0%, rgba(255, 236, 179, 0.3) 100%);
  border-radius: 12px;
  border-left: 4px solid var(--color-gold);
}

.modal-letter:empty {
  display: none;
}