body {
    font-family: sans-serif;
    background-color: #001f5b;
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}
.login-container, .alumnos-container {
    background: #000;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
}
.login-container img {
    width: 80px;
}
input, button {
    display: block;
    margin: 15px auto;
    padding: 10px;
    width: 80%;
}
button {
    background-color: #001f5b;
    color: #fff;
    border: none;
}
.error {
    color: red;
}

.menu-container {
    background: #000;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
}
.menu-container img {
    width: 80px;
    margin-bottom: 20px;
}
.menu-container h2 {
    margin-bottom: 30px;
}
.menu-container nav ul {
    list-style: none;
    padding: 0;
}
.menu-container nav ul li {
    margin: 15px 0;
}
.menu-container nav ul li a {
    color: #fff;
    text-decoration: none;
    font-size: 18px;
    background: #001f5b;
    padding: 10px 20px;
    border-radius: 8px;
    display: inline-block;
}
.menu-container nav ul li a:hover {
    background: #003580;
}