body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

header {
    background-color: #333;
    color: #fff;
    padding: 20px;
    text-align: center;
}

main {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: calc(100vh - 160px);
}

section {
    margin: 0 20px;
}

.login-form {
    width: 300px;
}

.login-form h2 {
    border-bottom: 2px solid #333;
    padding-bottom: 10px;
}

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

.form-group label {
    display: block;
    margin-bottom: 5px;
}

.form-group input {
    width: 100%;
    padding: 8px;
    border: 1px solid #ccc;
    border-radius: 4px;
}

button {
    padding: 10px 20px;
    background-color: #333;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

button:hover {
    background-color: #555;
}

.opciones {
    width: 200px;
}

.opciones h2 {
    border-bottom: 2px solid #333;
    padding-bottom: 10px;
}

.opciones ul {
    list-style: none;
    padding: 0;
}

.opciones ul li {
    margin-bottom: 10px;
}

footer {
    background-color: #333;
    color: #fff;
    text-align: center;
    padding: 10px 0;
    position: fixed;
    bottom: 0;
    width: 100%;
}