:root {
    --primary-color: #3b82f6;
    --secondary-color: #10b981;
    --accent-color: #f59e0b;
    --text-color: #374151;
    --text-light: #6b7280;
    --bg-color: #f9fafb;
    --card-bg: #ffffff;
    --border-color: #e5e7eb;
    --code-bg: #f3f4f6;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
}

* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
}

header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-align: center;
    padding: 2rem 1rem;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2.5rem;
    margin: 0 0 0.5rem 0;
    font-weight: 700;
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin: 0;
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem 2rem 1rem;
}

.section {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--border-color);
}

.section h2 {
    color: var(--primary-color);
    font-size: 1.8rem;
    margin: 0 0 1.5rem 0;
    font-weight: 600;
}

.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.info-card {
    background: var(--bg-color);
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    text-align: center;
}

.info-card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin: 0 0 1rem 0;
    color: var(--text-color);
}

.info-card .value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.info-card .description {
    font-size: 0.9rem;
    color: var(--text-light);
}

.example-container {
    margin: 2rem 0;
}

.example-container h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.image-comparison {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1rem;
}

.image-example {
    text-align: center;
}

.test-image {
    width: 100px;
    height: 100px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    display: block;
    margin-bottom: 0.5rem;
}

.image-label {
    font-size: 0.9rem;
    color: var(--text-light);
    font-weight: 500;
}

.media-query-demo {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.density-box {
    padding: 1rem;
    text-align: center;
    border-radius: 8px;
    font-weight: 600;
    color: white;
    background: var(--text-light);
}

.density-box.ldpi {
    background: #9ca3af;
}

.density-box.mdpi {
    background: var(--primary-color);
}

.density-box.hdpi {
    background: var(--secondary-color);
}

.density-box.xhdpi {
    background: var(--accent-color);
}

.density-box.xxhdpi {
    background: #8b5cf6;
}

.density-box.xxxhdpi {
    background: #ef4444;
}

/* Density-specific media queries */
@media screen and (-webkit-device-pixel-ratio: 0.75) {
    .density-box.ldpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

@media screen and (-webkit-device-pixel-ratio: 1) {
    .density-box.mdpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

@media screen and (-webkit-device-pixel-ratio: 1.5) {
    .density-box.hdpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

@media screen and (-webkit-device-pixel-ratio: 2) {
    .density-box.xhdpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

@media screen and (-webkit-device-pixel-ratio: 3) {
    .density-box.xxhdpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

@media screen and (-webkit-device-pixel-ratio: 4) {
    .density-box.xxxhdpi {
        background: #10b981;
        transform: scale(1.1);
    }
}

.test-container {
    margin: 2rem 0;
    padding: 1.5rem;
    background: var(--bg-color);
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.test-container h3 {
    font-size: 1.2rem;
    margin: 0 0 1rem 0;
    color: var(--text-color);
}

.canvas-container {
    text-align: center;
}

#pixel-canvas {
    border: 2px solid var(--border-color);
    border-radius: 4px;
    background: white;
    display: block;
    margin: 0 auto 1rem auto;
}

.canvas-controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.canvas-controls button {
    padding: 0.5rem 1rem;
    border: 1px solid var(--primary-color);
    background: var(--primary-color);
    color: white;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.2s;
}

.canvas-controls button:hover {
    background: #2563eb;
}

#responsive-image-container {
    text-align: center;
}

#responsive-image {
    border: 2px solid var(--border-color);
    border-radius: 8px;
    max-width: 100%;
    height: auto;
}

.image-info {
    margin-top: 1rem;
    font-size: 0.9rem;
    color: var(--text-light);
}

.code-container {
    margin: 1.5rem 0;
}

.code-container h3 {
    font-size: 1.2rem;
    margin: 0 0 1rem 0;
    color: var(--text-color);
}

pre {
    background: var(--code-bg);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 1rem;
    overflow-x: auto;
    margin: 0;
}

code {
    font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
    font-size: 0.85rem;
    line-height: 1.5;
}

footer {
    background: var(--text-color);
    color: white;
    text-align: center;
    padding: 2rem;
    margin-top: 2rem;
}

footer p {
    margin: 0;
    opacity: 0.8;
}

/* Responsive design */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .info-grid {
        grid-template-columns: 1fr;
    }
    
    .image-comparison {
        gap: 1rem;
    }
    
    .media-query-demo {
        grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    }
    
    .section {
        padding: 1.5rem;
        margin-bottom: 1.5rem;
    }
}

@media (max-width: 480px) {
    main {
        padding: 0 0.5rem 1rem 0.5rem;
    }
    
    header {
        padding: 1.5rem 1rem;
    }
    
    .section {
        padding: 1rem;
    }
    
    .canvas-controls {
        flex-direction: column;
        align-items: center;
    }
    
    .canvas-controls button {
        width: 100%;
        max-width: 200px;
    }
}

/* High DPI optimizations */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .test-image {
        image-rendering: -webkit-optimize-contrast;
        image-rendering: crisp-edges;
    }
}

/* Animation for density boxes */
.density-box {
    transition: all 0.3s ease;
}

.density-box:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}