body {
    font-family: -apple-system, Segoe UI, Roboto, sans-serif;
    background: #f4f6f8;
    margin: 0;
    padding: 2rem;
}

.container {
    max-width: 640px;
    margin: 0 auto;
    background: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.1);
}

h1 {
    margin-top: 0;
}

form {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

label {
    font-weight: 600;
    font-size: 0.9rem;
}

input[type="file"],
input[type="number"] {
    padding: 0.5rem;
    border: 1px solid #ccc;
    border-radius: 4px;
}

button {
    margin-top: 0.5rem;
    padding: 0.65rem 1.25rem;
    background: #2563eb;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
}

button:hover {
    background: #1d4ed8;
}

.alert {
    padding: 0.75rem 1rem;
    border-radius: 4px;
    margin-top: 1rem;
}

.alert.error {
    background: #fee2e2;
    color: #991b1b;
}

.downloads a {
    display: inline-block;
    margin-right: 1rem;
    padding: 0.6rem 1.1rem;
    background: #16a34a;
    color: #fff;
    border-radius: 4px;
    text-decoration: none;
}

.downloads a:hover {
    background: #15803d;
}