/* Claude AI Performance CSS - Optimizations & Best Practices */

/* === GPU ACCELERATION === */

/* Force GPU acceleration for smooth animations */
.gpu-accelerated,
.generate-btn,
.template-card,
.model-card,
.selection-btn,
.filter-btn,
.editor-btn,
.modal-overlay,
.toast {
    will-change: transform;
    transform: translateZ(0);
    backface-visibility: hidden;
    perspective: 1000px;
}

/* === EFFICIENT TRANSITIONS === */

/* Only animate specific properties for better performance */
.template-card,
.model-card,
.history-item {
    transition: 
        transform var(--transition-normal),
        box-shadow var(--transition-normal),
        border-color var(--transition-normal);
}

.selection-btn {
    transition: 
        transform var(--transition-normal),
        box-shadow var(--transition-normal),
        border-color var(--transition-normal),
        background-color var(--transition-normal);
}

.generate-btn {
    transition:
        transform var(--transition-normal),
        box-shadow var(--transition-normal),
        filter var(--transition-normal);
}

/* === CONTAIN LAYOUT SHIFTS === */

/* Prevent layout recalculation during animations */
.template-gallery,
.model-gallery,
.modal {
    contain: layout style paint;
}

.gallery-content,
.modal-content {
    contain: layout style paint;
    transform: translateZ(0);
}

.templates-grid,
.models-grid,
.history-grid {
    contain: layout style paint;
}

/* === OPTIMIZE REPAINTS === */

/* Minimize repaint area */
.toast-container {
    contain: layout style paint;
}

.editor-container {
    contain: layout;
}

.progress-spinner {
    contain: strict;
}

/* === SKELETON LOADERS === */

/* High-performance skeleton loading */
.skeleton-loader {
    background: linear-gradient(
        90deg,
        var(--gray-100) 25%,
        var(--gray-200) 50%,
        var(--gray-100) 75%
    );
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s infinite;
    border-radius: var(--radius-md);
    will-change: background-position;
}

@keyframes skeleton-loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* Skeleton variants */
.skeleton-text {
    height: 1rem;
    margin-bottom: 0.5rem;
}

.skeleton-title {
    height: 1.5rem;
    width: 70%;
    margin-bottom: 1rem;
}

.skeleton-card {
    height: 140px;
    border-radius: var(--radius-xl);
}

.skeleton-button {
    height: 40px;
    width: 120px;
    border-radius: var(--radius-lg);
}

/* === LOADING INDICATORS === */

/* Optimized spinner */
.loading-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--gray-200);
    border-top: 2px solid var(--orange-500);
    border-radius: var(--radius-full);
    animation: spin 1s linear infinite;
    will-change: transform;
    contain: strict;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Large spinner for main loading states */
.loading-spinner-lg {
    width: 32px;
    height: 32px;
    border-width: 3px;
}

/* Small spinner for inline loading */
.loading-spinner-sm {
    width: 16px;
    height: 16px;
    border-width: 2px;
}

/* === MEMORY OPTIMIZATIONS === */

/* Limit animations on low-end devices */
@media (max-width: 480px) and (max-height: 640px) {
    .template-card,
    .model-card,
    .selection-btn {
        transition-duration: 0.15s;
    }
    
    .hover-lift:hover,
    .card-float:hover {
        transform: translateY(-1px);
    }
    
    .skeleton-loading {
        animation-duration: 2s;
    }
}

/* Reduce complexity on very small screens */
@media (max-width: 320px) {
    .template-card,
    .model-card,
    .history-item {
        box-shadow: var(--shadow-sm);
    }
    
    .template-card:hover,
    .model-card:hover,
    .history-item:hover {
        box-shadow: var(--shadow-md);
        transform: none;
    }
    
    .generate-btn::before,
    .selection-btn::before {
        display: none;
    }
}

/* === CRITICAL CSS INLINING === */

/* Mark critical above-the-fold styles */
.critical-layout {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.critical-header {
    flex-shrink: 0;
}

.critical-main {
    flex: 1;
}

/* === FONT LOADING OPTIMIZATIONS === */

/* Prevent layout shift during font loading */
.font-loading {
    font-display: swap;
    font-family: 
        'Inter', 
        system-ui, 
        -apple-system, 
        'Segoe UI', 
        Roboto, 
        sans-serif;
}

/* === INTERSECTION OBSERVER OPTIMIZATIONS === */

/* Lazy loading states */
.lazy-load {
    opacity: 0;
    transform: translateY(20px);
    transition: 
        opacity 0.3s ease-out,
        transform 0.3s ease-out;
}

.lazy-load.loaded {
    opacity: 1;
    transform: translateY(0);
}

.lazy-load.loading {
    opacity: 0.5;
}

/* === SCROLL PERFORMANCE === */

/* Smooth scrolling with GPU acceleration */
.smooth-scroll {
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    transform: translateZ(0);
    will-change: scroll-position;
}

/* Optimize scroll containers */
.gallery-content,
.modal-content {
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    transform: translateZ(0);
}

/* === HOVER PERFORMANCE === */

/* Efficient hover states using transform */
.hover-optimize {
    transition: transform var(--transition-normal);
}

.hover-optimize:hover {
    transform: translateY(-2px) translateZ(0);
}

/* === ANIMATION PERFORMANCE === */

/* Use transform and opacity for better performance */
@keyframes fade-in-optimized {
    from { 
        opacity: 0;
        transform: translateZ(0);
    }
    to { 
        opacity: 1;
        transform: translateZ(0);
    }
}

@keyframes slide-up-optimized {
    from {
        opacity: 0;
        transform: translateY(20px) translateZ(0);
    }
    to {
        opacity: 1;
        transform: translateY(0) translateZ(0);
    }
}

/* === PREFETCH OPTIMIZATIONS === */

/* Preload critical resources */
.preload-fonts {
    font-family: 'Inter', sans-serif;
}

.preload-images {
    content: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg"/>');
}

/* === BROWSER COMPATIBILITY === */

/* Ensure compatibility with older browsers */
.compat-fallback {
    /* Fallback for browsers that don't support CSS variables */
    border-radius: 12px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

/* CSS Grid fallback */
@supports not (display: grid) {
    .templates-grid,
    .models-grid,
    .history-grid {
        display: flex;
        flex-wrap: wrap;
        gap: 1rem;
    }
    
    .template-card,
    .model-card,
    .history-item {
        flex: 1 1 300px;
        max-width: calc(50% - 0.5rem);
    }
}

/* Flexbox gap fallback */
@supports not (gap: 1rem) {
    .templates-grid > *,
    .models-grid > *,
    .history-grid > * {
        margin-bottom: 1rem;
        margin-right: 1rem;
    }
    
    .templates-grid > *:last-child,
    .models-grid > *:last-child,
    .history-grid > *:last-child {
        margin-right: 0;
    }
}

/* === PERFORMANCE MONITORING === */

/* Add performance hints */
.performance-hint {
    content-visibility: auto;
    contain-intrinsic-size: 1px 500px;
}

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

@media (prefers-reduced-motion: reduce) {
    .gpu-accelerated,
    .template-card,
    .model-card,
    .selection-btn {
        transition: none;
        animation: none;
        transform: none;
        will-change: auto;
    }
    
    .loading-spinner {
        animation: none;
        border: 2px solid var(--orange-500);
    }
    
    .skeleton-loader {
        animation: none;
        background: var(--gray-200);
    }
}

/* === PRINT OPTIMIZATIONS === */

@media print {
    .gpu-accelerated,
    .loading-spinner,
    .skeleton-loader {
        animation: none !important;
        transition: none !important;
        transform: none !important;
        will-change: auto !important;
    }
    
    .template-card,
    .model-card,
    .history-item {
        box-shadow: none !important;
        break-inside: avoid;
    }
}