body {
    font-family: Arial, sans-serif;
    text-align: center;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
}

.navbar {
    background-color: #007bff;
    color: white;
    padding: 15px;
    text-align: center;
    font-size: 1.5rem;
}

.cardre {
    max-width: 400px;
    margin: 50px auto;
    padding: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.1);
}

input, select, button {
    width: 90%;
    padding: 10px;
    margin: 10px 0;
    border-radius: 5px;
    border: 1px solid #ccc;
}

button {
    background-color: #007bff;
    color: white;
    border: none;
    cursor: pointer;
    transition: 0.3s;
}

button:hover {
    background-color: #0056b3;
}

.select-group {
    display: flex;
    justify-content: space-between;
}

#swap {
    width: 40px;
    border: none;
    background: #007bff;
    color: white;
    cursor: pointer;
}