/**
 * ============================================================================
 * ANIMATION PHILOSOPHY & KEYFRAMES - ANIMATIONS.CSS
 * Project: Malik Tayyab Jamil - Portfolio Architecture
 * Rules: 60fps GPU-Accelerated (transform & opacity only), Reduced Motion Safe
 * ============================================================================
 */

/* ==========================================================================
 * 1. KEYFRAME DEFINITIONS
 * ========================================================================== */

/* Fade In Up Reveal */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Subtle Floating Breathing Movement */
@keyframes floatSlow {
  0%, 100% {
    transform: translateY(0px) rotate(0deg);
  }
  50% {
    transform: translateY(-8px) rotate(0.5deg);
  }
}

/* Subtle Pulse Glow for Live Indicators */
@keyframes pulseGlow {
  0% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4);
  }
  70% {
    box-shadow: 0 0 0 10px rgba(16, 185, 129, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
  }
}

/* Gold Accent Shimmer */
@keyframes goldShimmer {
  0% {
    background-position: -200% 0;
  }
  100% {
    background-position: 200% 0;
  }
}

/* Progress Line Animation */
@keyframes fillProgress {
  from { width: 0%; }
  to { width: 100%; }
}

/* Ripple Click Wave Animation */
@keyframes rippleWave {
  0% {
    width: 0px;
    height: 0px;
    opacity: 0.5;
  }
  100% {
    width: 300px;
    height: 300px;
    opacity: 0;
  }
}

/* Subtitle Blinking Cursor */
@keyframes cursorBlink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

/* Tech Badge Gentle Pulse */
@keyframes badgeGlowPulse {
  0%, 100% {
    border-color: var(--color-border);
  }
  50% {
    border-color: var(--color-accent);
  }
}

/* ==========================================================================
 * 2. REUSABLE ANIMATION UTILITY CLASSES
 * ========================================================================== */
.animate-fade-in {
  animation: fadeInUp 0.6s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.delay-1 { animation-delay: 100ms; }
.delay-2 { animation-delay: 200ms; }
.delay-3 { animation-delay: 300ms; }
.delay-4 { animation-delay: 400ms; }

/* Gentle Floating Effect */
.animate-float {
  animation: floatSlow 6s ease-in-out infinite;
}

/* Scroll Reveal Classes (Driven by js/animations.js via IntersectionObserver) */
.reveal-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

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

.reveal-left {
  opacity: 0;
  transform: translateX(-35px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

.reveal-left.is-visible {
  opacity: 1;
  transform: translateX(0);
}

.reveal-right {
  opacity: 0;
  transform: translateX(35px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

.reveal-right.is-visible {
  opacity: 1;
  transform: translateX(0);
}

.reveal-scale {
  opacity: 0;
  transform: scale(0.92);
  transition: opacity 600ms cubic-bezier(0.16, 1, 0.3, 1), transform 600ms cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}

.reveal-scale.is-visible {
  opacity: 1;
  transform: scale(1);
}

/* Stagger Children Container */
.stagger-container .stagger-item {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 500ms ease-out, transform 500ms ease-out;
  will-change: opacity, transform;
}

.stagger-container.is-visible .stagger-item {
  opacity: 1;
  transform: translateY(0);
}

.stagger-container.is-visible .stagger-item:nth-child(1) { transition-delay: 60ms; }
.stagger-container.is-visible .stagger-item:nth-child(2) { transition-delay: 120ms; }
.stagger-container.is-visible .stagger-item:nth-child(3) { transition-delay: 180ms; }
.stagger-container.is-visible .stagger-item:nth-child(4) { transition-delay: 240ms; }
.stagger-container.is-visible .stagger-item:nth-child(5) { transition-delay: 300ms; }
.stagger-container.is-visible .stagger-item:nth-child(6) { transition-delay: 360ms; }
.stagger-container.is-visible .stagger-item:nth-child(7) { transition-delay: 420ms; }
.stagger-container.is-visible .stagger-item:nth-child(8) { transition-delay: 480ms; }

/* ==========================================================================
 * 3. HERO CANVAS & DYNAMIC TYPEWRITER
 * ========================================================================== */
.hero-section {
  position: relative;
  overflow: hidden;
}

.hero-particles-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  opacity: 0.65;
}

.hero-content, .hero-portrait-wrapper {
  position: relative;
  z-index: 1;
}

/* Typewriter Subtitle Container */
.hero-subtitle {
  display: inline-flex;
  align-items: center;
  min-height: 1.4em;
}

.typewriter-cursor {
  display: inline-block;
  width: 2.5px;
  height: 1.1em;
  background-color: var(--color-accent);
  margin-left: 4px;
  animation: cursorBlink 0.9s step-end infinite;
  vertical-align: middle;
  border-radius: 1px;
}

/* ==========================================================================
 * 4. 3D INTERACTIVE CARD TILT & GLARE REFLECTION
 * ========================================================================== */
.tilt-card {
  transition: transform 150ms cubic-bezier(0.16, 1, 0.3, 1), box-shadow 150ms cubic-bezier(0.16, 1, 0.3, 1);
  transform-style: preserve-3d;
  perspective: 1000px;
  position: relative;
  overflow: hidden;
}

.card-glare {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.22), transparent 70%);
  opacity: 0;
  transition: opacity 250ms ease;
  z-index: 10;
  border-radius: inherit;
}

.tilt-card:hover .card-glare {
  opacity: 1;
}

/* ==========================================================================
 * 5. CLICK RIPPLE EFFECT & MAGNETIC BUTTONS
 * ========================================================================== */
.btn, .icon-btn, .tech-badge, .nav-link, .stat-card, .fact-card {
  position: relative;
  overflow: hidden;
}

.ripple-wave {
  position: absolute;
  border-radius: 50%;
  background: rgba(212, 175, 55, 0.35);
  transform: translate(-50%, -50%);
  pointer-events: none;
  animation: rippleWave 600ms cubic-bezier(0, 0, 0.2, 1) forwards;
}

[data-theme="dark"] .ripple-wave {
  background: rgba(255, 255, 255, 0.25);
}

/* ==========================================================================
 * 6. FLOATING BACK TO TOP BUTTON WITH SVG PROGRESS RING
 * ========================================================================== */
.back-to-top-btn {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 52px;
  height: 52px;
  border-radius: var(--radius-full);
  background-color: var(--color-surface);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: var(--z-fixed);
  transition: opacity 300ms ease, transform 200ms cubic-bezier(0.16, 1, 0.3, 1), background-color 200ms ease, border-color 200ms ease;
}

.back-to-top-btn .progress-ring {
  position: absolute;
  inset: -1px;
  width: 52px;
  height: 52px;
  transform: rotate(-90deg);
  pointer-events: none;
}

.back-to-top-btn .progress-ring-circle {
  transition: stroke-dashoffset 100ms linear;
}

.back-to-top-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background-color: var(--color-surface-hover);
  transform: translateY(-4px) scale(1.08);
  box-shadow: var(--shadow-gold);
}

.back-to-top-btn:active {
  transform: translateY(0) scale(0.95);
}

.back-to-top-btn:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
}

/* ==========================================================================
 * 7. UTILITIES & ACCESSIBILITY
 * ========================================================================== */
.section-divider {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, transparent 0%, var(--color-border) 25%, var(--color-accent) 50%, var(--color-border) 75%, transparent 100%);
  margin-top: var(--space-12);
  margin-bottom: var(--space-12);
  opacity: 0.7;
}

.pulse-dot {
  width: 10px;
  height: 10px;
  background-color: var(--color-success);
  border-radius: 50%;
  display: inline-block;
  animation: pulseGlow 2s infinite;
}

/* ACCESSIBILITY: Prefers Reduced Motion override */
@media (prefers-reduced-motion: reduce) {
  .reveal-on-scroll,
  .reveal-left,
  .reveal-right,
  .reveal-scale,
  .stagger-container .stagger-item,
  .animate-fade-in,
  .animate-float {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
    animation: none !important;
  }

  .typewriter-cursor {
    animation: none !important;
    opacity: 1 !important;
  }

  .pulse-dot {
    animation: none !important;
  }

  .tilt-card {
    transform: none !important;
  }

  html {
    scroll-behavior: auto !important;
  }
}