* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Arial', sans-serif;
}

body {
    background-color: #f5f5f5;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

h1 {
    color: #333;
    margin-bottom: 30px;
    text-align: center;
}

.form-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: bold;
}

input[type="number"],
input[type="text"] {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
}

input[type="text"] {
    font-family: monospace;
}

small {
    color: #888;
    font-size: 12px;
}

button {
    background-color: #4CAF50;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 5px;
    font-size: 16px;
    cursor: pointer;
    width: 100%;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #45a049;
}

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

.loading {
    text-align: center;
    padding: 20px;
}

.spinner {
    width: 40px;
    height: 40px;
    margin: 0 auto;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #4CAF50;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.result {
    margin-top: 20px;
    padding: 20px;
    border-radius: 5px;
}

.success {
    color: #28a745;
    margin-bottom: 10px;
    font-weight: bold;
}

.error {
    color: #dc3545;
    margin-bottom: 10px;
}

.download-link {
    display: inline-block;
    background-color: #007bff;
    color: white;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    transition: background-color 0.3s;
}

.download-link:hover {
    background-color: #0056b3;
}

.hidden {
    display: none;
}

.error-text {
    color: #dc3545;
    font-size: 12px;
    margin-top: 4px;
}