.contenido {
    background: linear-gradient(to bottom, #f0fdff, white);
}
.footer {
    position: relative;
    bottom: 0;
    width: 100%;
    height: 60px; /* Set the fixed height of the footer here */
    line-height: 60px; /* Vertically center the text there */
    background-color: #1e1e1e;
}