/**
 * Lazy Loading Images CSS
 * Story 1.5 - Skeleton Loaders + Fade-in Transitions
 *
 * @package SmartDuck
 * @since Story 1.5
 */

/* AC 5.3-5.4: Skeleton loader pour images lazy (réutilise pattern Story 1.2) */
.lazy-image-container {
    position: relative;
    overflow: hidden;
}

/* AC 5.3: Shimmer animation pendant chargement (Story 1.2 pattern) */
.lazy-image-container.loading::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: skeleton-shimmer 1.5s infinite linear;
    z-index: 1;
}

/* Shimmer animation avec transform (Story 1.2 learning: GPU-accelerated) */
@keyframes skeleton-shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* AC 4.4: Fade-in 300ms après chargement (Story 1.3 timing standard) */
.lazy-image {
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
}

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

/* Error state styling */
.lazy-image.error {
    opacity: 0.5;
    filter: grayscale(100%);
}

/* AC 6.2: Aspect ratio CSS pour images responsive (CLS < 0.1) */
.lazy-image-container {
    position: relative;
}

.lazy-image-container img {
    width: 100%;
    height: auto;
    display: block;
}

/* prefers-reduced-motion support (Story 1.3 learning: WCAG 2.1 AA) */
@media (prefers-reduced-motion: reduce) {
    .lazy-image {
        transition: none !important;
    }

    .lazy-image-container.loading::before {
        animation: none !important;
    }
}