/* 
   Animations Stylesheet
   Dedicated animation styles for University Site Modernization
   Uses GPU-accelerated properties (transform, opacity) for performance
*/

/* =========================================
   Entrance Animations
   ========================================= */

/* Fade Up Animation */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Fade In Animation */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* Fade In Up (for staggered cards) */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Scale In Animation */
@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* =========================================
   Animation Classes
   ========================================= */

/* Elements with data-animate attribute start hidden */
[data-animate] {
  opacity: 0;
}

/* Fade up animation trigger */
[data-animate="fade-up"] {
  animation: fadeUp 0.8s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* Fade in animation trigger */
[data-animate="fade-in"] {
  animation: fadeIn 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* Scale in animation trigger */
[data-animate="scale-in"] {
  animation: scaleIn 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* Animation delays for staggered effects */
[data-delay="100"] { animation-delay: 0.1s; }
[data-delay="200"] { animation-delay: 0.2s; }
[data-delay="300"] { animation-delay: 0.3s; }
[data-delay="400"] { animation-delay: 0.4s; }
[data-delay="500"] { animation-delay: 0.5s; }
[data-delay="600"] { animation-delay: 0.6s; }

/* =========================================
   Homepage Enhancements
   ========================================= */

/* Parallax Background Effect */
.hero-visual {
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: transform;
}

/* Enhanced Year Card Hover Effects */
.year-card {
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: transform, box-shadow;
}

.year-card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: 0 20px 40px -15px rgba(99, 102, 241, 0.4);
}

/* =========================================
   Year Pages - 3D Card Effects
   ========================================= */

/* Subject Card Base Styles */
.subject-card {
  transform-style: preserve-3d;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: transform;
  opacity: 0;
  animation: fadeInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

/* 3D Hover Effect */
.subject-card:hover {
  transform: perspective(1000px) rotateX(5deg) rotateY(-5deg) translateY(-10px);
}

/* Card Header with Animated Gradient */
.card-header-img {
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), 
              background-size 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  background-size: 150%;
  background-position: center;
  will-change: transform, background-size;
}

.subject-card:hover .card-header-img {
  transform: translateZ(20px);
  background-size: 160%;
}

/* Staggered Animation Delays for Subject Cards */
.subject-card:nth-child(1) { animation-delay: 0.1s; }
.subject-card:nth-child(2) { animation-delay: 0.2s; }
.subject-card:nth-child(3) { animation-delay: 0.3s; }
.subject-card:nth-child(4) { animation-delay: 0.4s; }
.subject-card:nth-child(5) { animation-delay: 0.5s; }
.subject-card:nth-child(6) { animation-delay: 0.6s; }
.subject-card:nth-child(7) { animation-delay: 0.7s; }
.subject-card:nth-child(8) { animation-delay: 0.8s; }
.subject-card:nth-child(9) { animation-delay: 0.9s; }
.subject-card:nth-child(10) { animation-delay: 1.0s; }

/* =========================================
   Portfolio & Stats Sections
   ========================================= */

/* Social Card Hover Effect */
.social-card {
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
              border-color 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: transform;
}

.social-card:hover {
  transform: translateY(-5px);
}

/* Stat Card Hover Effect */
.stat-card {
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
              border-color 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: transform;
}

.stat-card:hover {
  transform: translateY(-3px);
}

/* Battery Bar Animation */
.battery-bar {
  transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  will-change: width;
}

/* =========================================
   Performance Optimizations
   ========================================= */

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

/* GPU Acceleration Hints */
.year-card,
.subject-card,
.social-card,
.stat-card,
.hero-visual {
  transform: translateZ(0);
  backface-visibility: hidden;
}

/* =========================================
   Scroll Animations triggered by JS
   ========================================= */

.scroll-animate {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), 
                transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: opacity, transform;
}

.scroll-animate.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* Staggering modifiers for grouped items */
.scroll-animate.delay-100 { transition-delay: 0.1s; }
.scroll-animate.delay-200 { transition-delay: 0.2s; }
.scroll-animate.delay-300 { transition-delay: 0.3s; }
.scroll-animate.delay-400 { transition-delay: 0.4s; }