body {
    font-family: Arial, Helvetica, sans-serif;
    background: #f0f0f0;
    margin: 0;
    padding: 10px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: #ffffff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

h1 {
    text-align: center;
    color: #333;
}

p {
    text-align: center;
    color: #666;
}

.controls {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 15px;
    margin: 20px 0;
    justify-content: center;
}

.controls label {
    font-weight: bold;
}

#thickness {
    width: 250px;
}

#thicknessValue {
    min-width: 30px;
    font-weight: bold;
}

.buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin: 20px 0;
}

button {
    padding: 12px 24px;
    font-size: 16px;
    background: #007bff;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}

button:hover:not(:disabled) {
    background: #0056b3;
}

button:disabled {
    background: #cccccc;
    cursor: not-allowed;
}

input[type="file"] {
    display: block;
    margin: 20px auto;
    padding: 10px;
    font-size: 16px;
}

.preview {
    margin-top: 30px;
    text-align: center;
}

#canvas {
    max-width: 100%;
    height: auto;
    border: 3px solid #ddd;
    background: white;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}