/**
 * Lazy Loading Styles
 */

/* 로딩 전 placeholder */
img[data-src],
img.lazy {
    background-color: #f0f0f0;
    background-image: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
}

/* 로딩 중 */
.lazy-loading {
    opacity: 0.5;
    transition: opacity 0.3s ease;
}

/* 로딩 완료 */
.lazy-loaded {
    opacity: 1;
    animation: fadeIn 0.3s ease;
}

/* 로딩 실패 */
.lazy-error {
    background-color: #f8f8f8;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100' height='100' viewBox='0 0 100 100'%3E%3Crect fill='%23f0f0f0' width='100' height='100'/%3E%3Ctext x='50' y='50' font-family='Arial' font-size='12' fill='%23999' text-anchor='middle' dy='.3em'%3ENo Image%3C/text%3E%3C/svg%3E");
    background-size: cover;
    background-position: center;
}

/* Shimmer 애니메이션 */
@keyframes shimmer {
    0% {
        background-position: -200% 0;
    }
    100% {
        background-position: 200% 0;
    }
}

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

/* iframe lazy loading */
iframe[data-src] {
    background-color: #f0f0f0;
}

/* 배경 이미지 lazy loading */
[data-bg] {
    background-color: #f0f0f0;
}

[data-bg].lazy-loaded {
    background-color: transparent;
}

/* Native lazy loading 지원 */
img[loading="lazy"] {
    /* 네이티브 지원 시 애니메이션 없음 */
}