body {
    font-family: Arial, sans-serif;
    background: #f2f4f7;
    margin: 0;
    padding: 30px;
    color: #1f2937;
}

.container {
    max-width: 900px;
    margin: auto;
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

h2 {
    margin-top: 0;
    font-size: 22px;
}

.controls {
    display: flex;
    gap: 10px;
    margin: 15px 0;
    flex-wrap: wrap;
}

input[type="file"] {
    padding: 6px;
}

button {
    padding: 8px 14px;
    border: 1px solid #d1d5db;
    background: #fff;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.15s;
}

button:hover {
    background: #f3f4f6;
}

textarea {
    width: 100%;
    height: 180px;
    margin-top: 10px;
    padding: 10px;
    border: 1px solid #d1d5db;
    border-radius: 8px;
    font-family: monospace;
    background: #fafafa;
}

#preview {
    margin-top: 15px;
    width: 100%;
    max-height: 420px;
    object-fit: contain;
    border-radius: 10px;
    border: 1px solid #e5e7eb;
    background: #fff;
}