/**
 * Krioft Enhanced Lazy Loading CSS
 * Advanced styles for progressive image loading with smooth transitions
 */

/* Base styles for lazy loading images */
.krioft-lazy {
    opacity: 0;
    transition: opacity 0.4s cubic-bezier(0.4, 0, 0.2, 1), 
                transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    background-color: #f8f9fa;
    background-image: linear-gradient(45deg, #e9ecef 25%, transparent 25%), 
                      linear-gradient(-45deg, #e9ecef 25%, transparent 25%), 
                      linear-gradient(45deg, transparent 75%, #e9ecef 75%), 
                      linear-gradient(-45deg, transparent 75%, #e9ecef 75%);
    background-size: 16px 16px;
    background-position: 0 0, 0 8px, 8px -8px, -8px 0px;
    will-change: opacity, transform;
}

/* Loading state - when image is being fetched */
.krioft-lazy.krioft-lazy-loading {
    opacity: 0.7;
    animation: krioft-pulse 1.2s ease-in-out infinite;
    background-image: linear-gradient(45deg, #dee2e6 25%, transparent 25%), 
                      linear-gradient(-45deg, #dee2e6 25%, transparent 25%), 
                      linear-gradient(45deg, transparent 75%, #dee2e6 75%), 
                      linear-gradient(-45deg, transparent 75%, #dee2e6 75%);
}

/* Enhanced pulse animation for loading state */
@keyframes krioft-pulse {
    0%, 100% {
        opacity: 0.7;
        transform: scale(1);
    }
    50% {
        opacity: 0.9;
        transform: scale(1.01);
    }
}

/* Loaded state with smooth transition */
.krioft-lazy.krioft-lazy-loaded {
    opacity: 1;
    transform: scale(1);
    background: none;
    animation: krioft-fade-in-scale 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    will-change: auto;
}

/* Enhanced fade-in animation with subtle scale */
@keyframes krioft-fade-in-scale {
    0% {
        opacity: 0;
        transform: scale(0.98);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

/* Enhanced error state */
.krioft-lazy.krioft-lazy-error {
    opacity: 0.6;
    background: linear-gradient(135deg, #ffebee 0%, #ffcdd2 100%);
    background-image: none;
    animation: none;
    position: relative;
    border: 1px solid #ffcdd2;
    border-radius: 4px;
}

.krioft-lazy.krioft-lazy-error::after {
    content: "⚠️";
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: clamp(16px, 4vw, 24px);
    color: #d32f2f;
    text-shadow: 0 1px 2px rgba(0,0,0,0.1);
}

/* Observed state - prevents duplicate processing */
.krioft-lazy.krioft-lazy-observed {
    /* No visual changes, just a marker class */
}

/* Performance optimization for images outside viewport */
.krioft-lazy:not(.krioft-lazy-loaded):not(.krioft-lazy-loading) {
    content-visibility: auto;
    contain-intrinsic-size: 300px 200px;
}

/* Enhanced responsive improvements */
@media (max-width: 768px) {
    .krioft-lazy {
        background-size: 12px 12px;
        background-position: 0 0, 0 6px, 6px -6px, -6px 0px;
        transition-duration: 0.3s; /* Faster transitions on mobile */
    }

    .krioft-lazy.krioft-lazy-loading {
        animation-duration: 1s; /* Faster animation on mobile */
    }

    .krioft-lazy.krioft-lazy-loaded {
        animation-duration: 0.4s;
    }

    /* Smaller error icon on mobile */
    .krioft-lazy.krioft-lazy-error::after {
        font-size: clamp(14px, 3vw, 20px);
    }
}

/* Performance optimizations for slow connections */
@media (max-width: 480px) {
    .krioft-lazy {
        will-change: opacity; /* Reduce GPU usage on very small screens */
    }

    .krioft-lazy.krioft-lazy-loaded {
        animation: none; /* Skip animation on very small screens for performance */
        transition: opacity 0.2s ease;
    }
}

/* Accessibility: Reduce motion for users who prefer it */
@media (prefers-reduced-motion: reduce) {
    .krioft-lazy,
    .krioft-lazy.krioft-lazy-loading {
        animation: none;
        transition: opacity 0.2s ease;
    }

    .krioft-lazy {
        background: #f8f9fa;
        background-image: none;
    }

    .krioft-lazy.krioft-lazy-loading {
        background: #e9ecef;
    }

    .krioft-lazy.krioft-lazy-loaded {
        animation: none;
        transition: opacity 0.2s ease;
    }

    @keyframes krioft-pulse {
        0%, 100% { opacity: 0.7; }
        50% { opacity: 0.9; }
    }
}

/* High contrast mode support */
@media (prefers-contrast: more) {
    .krioft-lazy {
        background-color: #e0e0e0;
        background-image: linear-gradient(45deg, #d0d0d0 25%, transparent 25%), 
                          linear-gradient(-45deg, #d0d0d0 25%, transparent 25%), 
                          linear-gradient(45deg, transparent 75%, #d0d0d0 75%), 
                          linear-gradient(-45deg, transparent 75%, #d0d0d0 75%);
        border: 1px solid #bdbdbd;
    }

    .krioft-lazy.krioft-lazy-loading {
        background-color: #d0d0d0;
        border-color: #9e9e9e;
    }

    .krioft-lazy.krioft-lazy-error {
        background: #ffcdd2;
        border-color: #f44336;
    }

    .krioft-lazy.krioft-lazy-error::after {
        color: #b71c1c;
        text-shadow: none;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    .krioft-lazy {
        background-color: #2d3748;
        background-image: linear-gradient(45deg, #4a5568 25%, transparent 25%), 
                          linear-gradient(-45deg, #4a5568 25%, transparent 25%), 
                          linear-gradient(45deg, transparent 75%, #4a5568 75%), 
                          linear-gradient(-45deg, transparent 75%, #4a5568 75%);
    }

    .krioft-lazy.krioft-lazy-loading {
        background-image: linear-gradient(45deg, #718096 25%, transparent 25%), 
                          linear-gradient(-45deg, #718096 25%, transparent 25%), 
                          linear-gradient(45deg, transparent 75%, #718096 75%), 
                          linear-gradient(-45deg, transparent 75%, #718096 75%);
    }

    .krioft-lazy.krioft-lazy-error {
        background: linear-gradient(135deg, #742a2a 0%, #9b2c2c 100%);
        border-color: #fc8181;
    }
}

/* Print styles */
@media print {
    .krioft-lazy:not(.krioft-lazy-loaded) {
        opacity: 1 !important;
        background: none !important;
        animation: none !important;
    }
}