/**
 * 🎬 Smooth Animations - 60fps GPU-Accelerated
 * Zero-jank animations for app-like feel
 */

/* ========================================
   KEYFRAMES
   ======================================== */

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

@keyframes fadeOut {
  from {
    opacity: 1;
  }
  to {
    opacity: 0;
  }
}

/* Slide animations - GPU accelerated */
@keyframes slideInRight {
  from {
    transform: translate3d(100%, 0, 0);
    opacity: 0;
  }
  to {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
}

@keyframes slideOutLeft {
  from {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
  to {
    transform: translate3d(-100%, 0, 0);
    opacity: 0;
  }
}

@keyframes slideInLeft {
  from {
    transform: translate3d(-100%, 0, 0);
    opacity: 0;
  }
  to {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
}

@keyframes slideOutRight {
  from {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
  to {
    transform: translate3d(100%, 0, 0);
    opacity: 0;
  }
}

@keyframes slideInUp {
  from {
    transform: translate3d(0, 100%, 0);
    opacity: 0;
  }
  to {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
}

@keyframes slideOutDown {
  from {
    transform: translate3d(0, 0, 0);
    opacity: 1;
  }
  to {
    transform: translate3d(0, 100%, 0);
    opacity: 0;
  }
}

/* Scale animations */
@keyframes scaleIn {
  from {
    transform: scale3d(0.9, 0.9, 1);
    opacity: 0;
  }
  to {
    transform: scale3d(1, 1, 1);
    opacity: 1;
  }
}

@keyframes scaleOut {
  from {
    transform: scale3d(1, 1, 1);
    opacity: 1;
  }
  to {
    transform: scale3d(0.9, 0.9, 1);
    opacity: 0;
  }
}

/* Bounce */
@keyframes bounceIn {
  0% {
    transform: scale3d(0.3, 0.3, 1);
    opacity: 0;
  }
  50% {
    transform: scale3d(1.05, 1.05, 1);
  }
  70% {
    transform: scale3d(0.95, 0.95, 1);
  }
  100% {
    transform: scale3d(1, 1, 1);
    opacity: 1;
  }
}

/* Spinner */
@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

/* Pulse */
@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

/* Shimmer loading effect */
@keyframes shimmer {
  0% {
    background-position: -468px 0;
  }
  100% {
    background-position: 468px 0;
  }
}

/* Gradient animation */
@keyframes gradientShift {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

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

/* Page transitions */
.page-enter {
  animation: slideInRight var(--duration-normal) var(--ease-out) forwards;
}

.page-exit {
  animation: slideOutLeft calc(var(--duration-normal) * 0.8) var(--ease-in) forwards;
}

.page-enter-reverse {
  animation: slideInLeft var(--duration-normal) var(--ease-out) forwards;
}

.page-exit-reverse {
  animation: slideOutRight calc(var(--duration-normal) * 0.8) var(--ease-in) forwards;
}

/* Modal transitions */
.modal-enter {
  animation: scaleIn var(--duration-normal) var(--ease-out) forwards;
}

.modal-exit {
  animation: scaleOut calc(var(--duration-normal) * 0.8) var(--ease-in) forwards;
}

/* Sheet transitions (bottom drawer) */
.sheet-enter {
  animation: slideInUp var(--duration-normal) var(--ease-out) forwards;
}

.sheet-exit {
  animation: slideOutDown calc(var(--duration-normal) * 0.8) var(--ease-in) forwards;
}

/* Fade transitions */
.fade-enter {
  animation: fadeIn var(--duration-normal) var(--ease-out) forwards;
}

.fade-exit {
  animation: fadeOut calc(var(--duration-normal) * 0.8) var(--ease-in) forwards;
}

/* Loading states */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--gray-200) 0px,
    var(--gray-100) 40px,
    var(--gray-200) 80px
  );
  background-size: 468px;
  animation: shimmer 1.2s ease-in-out infinite;
}

.spinner {
  width: 24px;
  height: 24px;
  border: 2px solid var(--gray-200);
  border-top-color: var(--primary);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
}

.pulse {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* ========================================
   GESTURE FEEDBACK
   ======================================== */

/* Tap/Click feedback */
.tap-feedback {
  position: relative;
  overflow: hidden;
}

.tap-feedback::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width var(--duration-fast), height var(--duration-fast);
}

.tap-feedback:active::after {
  width: 100%;
  height: 100%;
}

/* Hover states (desktop) */
@media (hover: hover) {
  .hover-lift {
    transition: transform var(--duration-fast) var(--ease-out);
  }
  
  .hover-lift:hover {
    transform: translateY(-2px);
  }
  
  .hover-scale {
    transition: transform var(--duration-fast) var(--ease-out);
  }
  
  .hover-scale:hover {
    transform: scale(1.02);
  }
}

/* ========================================
   PERFORMANCE OPTIMIZATIONS
   ======================================== */

/* GPU acceleration hints */
.gpu-accelerated {
  transform: translateZ(0);
  will-change: transform;
}

.gpu-accelerated-opacity {
  transform: translateZ(0);
  will-change: opacity;
}

/* Prevent layout shifts during animations */
.no-layout-shift {
  contain: layout;
}

/* Smooth momentum scrolling (iOS) */
.smooth-scroll {
  -webkit-overflow-scrolling: touch;
  overflow-y: auto;
}

/* ========================================
   REDUCED MOTION
   ======================================== */

@media (prefers-reduced-motion: reduce) {
  .page-enter,
  .page-exit,
  .page-enter-reverse,
  .page-exit-reverse,
  .modal-enter,
  .modal-exit,
  .sheet-enter,
  .sheet-exit,
  .fade-enter,
  .fade-exit {
    animation: none !important;
  }
  
  .skeleton {
    animation: none !important;
    background: var(--gray-200);
  }
  
  .spinner {
    animation: spin 2s linear infinite;
  }
}