/**
 * Loading States and Animations
 * Smooth loading experiences and micro-interactions
 */

/* Loading Spinner Animations */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

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

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

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes shimmer {
    0% {
        background-position: -200px 0;
    }
    100% {
        background-position: calc(200px + 100%) 0;
    }
}

/* Page Loading States */
.page-loading {
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
}

.page-loaded {
    opacity: 1;
    animation: fadeInUp 0.6s ease-out;
}

/* Button Loading States */
.btn-loading {
    position: relative;
    pointer-events: none;
    color: transparent !important;
}

.btn-loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 16px;
    height: 16px;
    margin: -8px 0 0 -8px;
    border: 2px solid #ffffff;
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 0.8s linear infinite;
}

.btn-loading.btn-primary::after {
    border-color: white;
    border-top-color: transparent;
}

.btn-loading.btn-secondary::after {
    border-color: #64abde;
    border-top-color: transparent;
}

/* Form Loading States */
.form-loading {
    position: relative;
    opacity: 0.6;
    pointer-events: none;
}

.form-loading::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.8);
    border-radius: 8px;
    z-index: 10;
}

.form-loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 24px;
    height: 24px;
    margin: -12px 0 0 -12px;
    border: 3px solid #64abde;
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s linear infinite;
    z-index: 11;
}

/* Input Loading States */
.input-loading {
    background: linear-gradient(90deg, #f0f0f0 25%, transparent 37%, transparent 63%, #f0f0f0 75%);
    background-size: 200px 100%;
    animation: shimmer 1.5s infinite;
    color: transparent;
}

/* Card Loading (Skeleton) */
.card-loading {
    background: #f8f9fa;
    border-radius: 8px;
    overflow: hidden;
    position: relative;
}

.card-loading::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.6), transparent);
    animation: shimmer 1.5s infinite;
}

.skeleton-text {
    background: #e2e8f0;
    border-radius: 4px;
    height: 1em;
    margin: 0.5em 0;
}

.skeleton-text:nth-child(odd) {
    width: 80%;
}

.skeleton-text:nth-child(even) {
    width: 60%;
}

/* Image Loading States */
.image-loading {
    background: #f0f0f0;
    background-image: linear-gradient(90deg, #f0f0f0 25%, transparent 37%, transparent 63%, #f0f0f0 75%);
    background-size: 200px 100%;
    animation: shimmer 1.5s infinite;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
    font-size: 14px;
}

.image-loading::before {
    content: '📸 Loading...';
}

/* Progressive Image Enhancement */
.progressive-image {
    opacity: 0;
    transition: opacity 0.3s ease;
}

.progressive-image.loaded {
    opacity: 1;
}

.progressive-image.blur {
    filter: blur(5px);
    transition: filter 0.3s ease;
}

.progressive-image.blur.loaded {
    filter: blur(0);
}

/* Page Transition Loading */
.page-transition {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #5fcbef, #f7966e);
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.page-transition.active {
    opacity: 1;
    visibility: visible;
}

.page-transition .loading-content {
    text-align: center;
    color: white;
}

.page-transition .loading-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

/* Micro-interactions */
.hover-lift {
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.hover-lift:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.hover-scale {
    transition: transform 0.2s ease;
}

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

.hover-glow {
    transition: box-shadow 0.2s ease;
}

.hover-glow:hover {
    box-shadow: 0 0 20px rgba(100, 171, 222, 0.3);
}

/* Focus animations */
.focus-ring {
    transition: box-shadow 0.2s ease;
}

.focus-ring:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(100, 171, 222, 0.3);
}

/* Stagger animations for lists */
.stagger-animation > * {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 0.6s ease-out forwards;
}

.stagger-animation > *:nth-child(1) { animation-delay: 0.1s; }
.stagger-animation > *:nth-child(2) { animation-delay: 0.2s; }
.stagger-animation > *:nth-child(3) { animation-delay: 0.3s; }
.stagger-animation > *:nth-child(4) { animation-delay: 0.4s; }
.stagger-animation > *:nth-child(5) { animation-delay: 0.5s; }
.stagger-animation > *:nth-child(6) { animation-delay: 0.6s; }

/* Content loading reveal */
.reveal-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Loading dots animation */
.loading-dots::after {
    content: '';
    animation: loadingDots 1.5s steps(4, end) infinite;
}

@keyframes loadingDots {
    0%, 20% {
        content: '.';
    }
    40% {
        content: '..';
    }
    60% {
        content: '...';
    }
    80%, 100% {
        content: '';
    }
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .page-transition,
    .loading-spinner,
    .btn-loading::after {
        display: none !important;
    }
}