Free Online Code Editor | Write, Run & Share Code Instantly

HTML

<!DOCTYPE html>
<html>
<head>
    <title>My App</title>
</head>
<body>
    <h1 class="title">Hello World!</h1>
    <p>Edit this code to see live changes.</p>
    <button id="demo-btn">Click Me</button>
</body>
</html>

CSS

body {
    font-family: 'Inter', sans-serif;
    text-align: center;
    padding: 2rem;
    background: #f8fafc;
}

.title {
    color: #6366f1;
    margin-bottom: 1rem;
}

#demo-btn {
    padding: 0.75rem 1.5rem;
    background: #6366f1;
    color: white;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

#demo-btn:hover {
    background: #4f46e5;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

JavaScript

document.getElementById('demo-btn').addEventListener('click', function() {
    alert('Button clicked!');
});