/* 
 * RecyclingCoach Optimized Styles
 * Performance-focused CSS with modern features
 */

/* CSS Variables for consistent theming */
:root {
    --green-50: #f0fdf4;
    --green-100: #dcfce7;
    --green-200: #bbf7d0;
    --green-300: #86efac;
    --green-400: #4ade80;
    --green-500: #22c55e;
    --green-600: #16a34a;
    --green-700: #15803d;
    --green-800: #166534;
    --green-900: #14532d;
    
    --yellow-300: #fcd34d;
    --yellow-400: #fbbf24;
    --yellow-500: #f59e0b;
    
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    
    --radius-sm: 0.125rem;
    --radius: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --gray-50: #111827;
        --gray-100: #1f2937;
        --gray-800: #f3f4f6;
        --gray-900: #f9fafb;
    }
}

/* Performance: Use hardware acceleration */
* {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Smooth scrolling with reduced motion support */
@media (prefers-reduced-motion: no-preference) {
    html {
        scroll-behavior: smooth;
    }
}

/* Responsive container with fluid typography */
.container {
    width: 100%;
    margin-inline: auto;
    padding-inline: clamp(1rem, 5vw, 2rem);
}

@media (min-width: 640px) {
    .container { max-width: 640px; }
}

@media (min-width: 768px) {
    .container { max-width: 768px; }
}

@media (min-width: 1024px) {
    .container { max-width: 1024px; }
}

@media (min-width: 1280px) {
    .container { max-width: 1280px; }
}

@media (min-width: 1536px) {
    .container { max-width: 1536px; }
}

/* Optimized Hero Styles */
.hero-container {
    position: relative;
    width: 100%;
    height: clamp(300px, 50vw, 600px);
    overflow: hidden;
    background-color: var(--gray-100);
}

.hero-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
    will-change: transform;
}

/* Loading skeleton for images */
.image-skeleton {
    background: linear-gradient(90deg, var(--gray-200) 25%, var(--gray-100) 50%, var(--gray-200) 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

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

/* Enhanced card styles with modern effects */
.card {
    background-color: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: all var(--transition-base);
    contain: layout style paint;
}

.card-hover {
    position: relative;
    transform: translateZ(0);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    will-change: transform;
}

.card-hover::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, transparent, rgba(255, 255, 255, 0.2));
    opacity: 0;
    transition: opacity var(--transition-base);
    pointer-events: none;
}

.card-hover:hover {
    transform: translateY(-4px) scale(1.01);
    box-shadow: var(--shadow-xl);
}

.card-hover:hover::before {
    opacity: 1;
}

/* Optimized image containers */
.card-image-container {
    position: relative;
    height: 200px;
    overflow: hidden;
    background-color: var(--gray-100);
}

.card-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
    will-change: transform;
}

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

/* Featured cards with gradient overlay */
.featured-card {
    position: relative;
    overflow: hidden;
}

.featured-card::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.6), transparent 50%);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.featured-card:hover::after {
    opacity: 1;
}

/* Modern button styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    text-decoration: none;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transform: translateZ(0);
}

.btn::before {
    content: '';
    position: absolute;
    inset: 0;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.3) 0%, transparent 70%);
    transform: scale(0);
    transition: transform var(--transition-base);
}

.btn:hover::before {
    transform: scale(2);
}

.btn-primary {
    background-color: var(--green-600);
    color: white;
    box-shadow: var(--shadow);
}

.btn-primary:hover {
    background-color: var(--green-700);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: var(--yellow-400);
    color: var(--gray-900);
    box-shadow: var(--shadow);
}

.btn-secondary:hover {
    background-color: var(--yellow-500);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

/* Responsive grid with auto-fit */
.auto-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr));
    gap: 1.5rem;
}

/* Modern animations */
@keyframes fadeIn {
    from { 
        opacity: 0;
        transform: translateY(10px);
    }
    to { 
        opacity: 1;
        transform: translateY(0);
    }
}

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

.animate-fade-in {
    animation: fadeIn var(--transition-slow) ease-out;
}

.animate-slide-in {
    animation: slideIn var(--transition-slow) ease-out;
}

/* Lazy loading placeholder */
img[loading="lazy"] {
    background-color: var(--gray-100);
    min-height: 100px;
}

/* Improved accessibility */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.focus-visible:focus {
    outline: 2px solid var(--green-500);
    outline-offset: 2px;
}

/* Skip to content link */
.skip-link {
    position: absolute;
    top: -100%;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--green-600);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    text-decoration: none;
    z-index: 9999;
    transition: top var(--transition-fast);
}

.skip-link:focus {
    top: 1rem;
}

/* Responsive utilities */
@media (max-width: 767px) {
    .mobile-hide { display: none !important; }
}

@media (min-width: 768px) {
    .desktop-hide { display: none !important; }
}

/* Print styles for eco-friendly printing */
@media print {
    * {
        background: transparent !important;
        color: black !important;
        box-shadow: none !important;
        text-shadow: none !important;
    }
    
    a, a:visited {
        text-decoration: underline;
    }
    
    a[href]:after {
        content: " (" attr(href) ")";
    }
    
    img {
        max-width: 100% !important;
        page-break-inside: avoid;
    }
    
    @page {
        margin: 2cm;
    }
    
    h2, h3 {
        page-break-after: avoid;
    }
}

/* Performance: Reduce paint areas */
.will-change-transform {
    will-change: transform;
}

.will-change-opacity {
    will-change: opacity;
}

/* Custom scrollbar for better UX */
@supports (scrollbar-width: thin) {
    * {
        scrollbar-width: thin;
        scrollbar-color: var(--green-600) var(--gray-100);
    }
}

/* Webkit scrollbar */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--green-600);
    border-radius: var(--radius);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--green-700);
}

/* Focus trap for modals */
.focus-trap {
    position: fixed;
    inset: 0;
    z-index: 9998;
}

/* Responsive text utilities */
.text-balance {
    text-wrap: balance;
}

.text-pretty {
    text-wrap: pretty;
}

/* Modern aspect ratios */
.aspect-square { aspect-ratio: 1 / 1; }
.aspect-video { aspect-ratio: 16 / 9; }
.aspect-4-3 { aspect-ratio: 4 / 3; }

/* Optimized transitions */
.transition-colors {
    transition-property: background-color, border-color, color, fill, stroke;
    transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
    transition-duration: 150ms;
}

.transition-transform {
    transition-property: transform;
    transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
    transition-duration: 150ms;
}

.transition-all {
    transition-property: all;
    transition-timing-function: cubic-bezier(0.4, 0, 0.2, 1);
    transition-duration: 150ms;
}