Editor HTML y CSS en Tiempo Real

body {
    font-family: 'Segoe UI', Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
}

header {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    padding: 2rem;
    text-align: center;
    color: white;
    margin-bottom: 2rem;
    border-bottom: 2px solid rgba(255, 255, 255, 0.2);
}

header h1 {
    font-size: 3rem;
    margin: 0;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.2rem;
    margin: 0.5rem 0 0 0;
    opacity: 0.9;
}

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.card {
    background: white;
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}

.card h2 {
    color: #667eea;
    margin-top: 0;
    font-size: 1.8rem;
}

.card ul {
    list-style: none;
    padding: 0;
}

.card li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #eee;
    position: relative;
    padding-left: 1.5rem;
}

.card li:before {
    content: "✨";
    position: absolute;
    left: 0;
}

.card button {
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.3s ease;
    margin-top: 1rem;
}

.card button:hover {
    transform: scale(1.05);
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    main {
        grid-template-columns: 1fr;
        padding: 0 1rem;
    }
    
    .card {
        padding: 1.5rem;
    }
}

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🚀 Editor HTML & CSS