body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: #f4f7f6;
    color: #333;
    margin: 0;
}

header {
    width: 100%;
    text-align: center;
    padding: 1rem 0;
    background-color: #005f73;
    color: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: relative;
}

header a {
    position: absolute;
    top: 50%;
    left: 20px;
    transform: translateY(-50%);
    color: white;
    text-decoration: none;
    font-weight: bold;
}

.controls {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 20px;
    padding: 20px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin: 20px;
}

.controls label {
    font-weight: bold;
}

.controls select, .controls input {
    padding: 8px;
    border-radius: 4px;
    border: 1px solid #ccc;
}

canvas {
    border: 1px solid #ddd;
    background-color: white;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    max-width: 100%;
    height: auto;
}

@media (max-width: 600px) {
    .controls {
        flex-direction: column;
        align-items: stretch;
    }
    header h1 {
        font-size: 1.5rem;
    }
}