body {
    font-family: Arial, sans-serif;
    background: #f5f5f5;
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 500px;
    margin: 0 auto;
    background: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h1 {
    text-align: center;
    margin-bottom: 20px;
}

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

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

select, input[type="number"] {
    width: 100%;
    padding: 8px;
    font-size: 1em;
    border: 1px solid #ccc;
    border-radius: 4px;
}

button {
    width: 100%;
    padding: 12px;
    font-size: 1em;
    color: #fff;
    background: #007BFF;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button:hover {
    background: #0056b3;
}

.result {
    margin-top: 30px;
    background: #f0f0f0;
    padding: 15px;
    border-radius: 6px;
    min-height: 50px;
}