* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
    padding: 20px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background-color: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    color: #2c3e50;
}

h2 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.input-container {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 25px;
    align-items: flex-end;
}

.input-group {
    flex: 1;
    min-width: 150px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
}

button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #2980b9;
}

#download-btn {
    background-color: #27ae60;
    margin-top: 15px;
}

#download-btn:hover {
    background-color: #219653;
}

#result-preview {
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 4px;
    overflow-x: auto;
    max-height: 400px;
    border: 1px solid #ddd;
}

.hidden {
    display: none;
}

#loading {
    text-align: center;
    margin: 20px 0;
}

#error-container {
    background-color: #ffebee;
    color: #c62828;
    padding: 15px;
    border-radius: 4px;
    margin-top: 20px;
}