/* Cyberpunk Neon Style */
body {
    background: #0a0a0a;
}

.calculator {
    background: #1a1a1a;
    border: 2px solid #00f3ff;
    box-shadow: 
        0 0 10px #00f3ff,
        0 0 20px #00f3ff,
        0 0 40px #00f3ff;
    border-radius: 15px;
}

#display {
    background: #000;
    color: #00f3ff;
    text-shadow: 0 0 10px #00f3ff;
    border: 2px solid #00f3ff;
}

button {
    background: #1a1a1a;
    color: #00f3ff;
    border: 1px solid #00f3ff;
    box-shadow: 0 0 5px #00f3ff;
    transition: all 0.3s ease;
}

button:hover {
    background: #00f3ff;
    color: #000;
    box-shadow: 0 0 20px #00f3ff;
}

button.operator {
    color: #ff00ff;
    border-color: #ff00ff;
    box-shadow: 0 0 5px #ff00ff;
}

button.operator:hover {
    background: #ff00ff;
    color: #000;
    box-shadow: 0 0 20px #ff00ff;
}

button.equal {
    color: #00ff00;
    border-color: #00ff00;
    box-shadow: 0 0 5px #00ff00;
}

button.equal:hover {
    background: #00ff00;
    color: #000;
    box-shadow: 0 0 20px #00ff00;
}