#login
{
    position: absolute;
    left: 50vh;
    top: calc(50% - 75px);
    opacity: 0; 
    width: 300px;
    height: 150px;
    border: 1px solid lightgrey;
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
    align-items: center;
}

#login > div
{
    display: flex;
    flex-direction: row;
    justify-content: space-evenly;
    align-items: center;
}

#login > div > div, #login input
{
     width: 120px;

}

#menu ul
{
    list-style-type: none;
    display: flex;
}

#menu
{
    display: none;
}

#menu ul li
{
   width: 150px;
   height: 20px;
   background-color: #ebe7e7;
   margin-right: 20px;
   text-align: center;
   border: 1px solid lightgrey;
   border-radius: 4px;
}

#contenido
{
    display: none;
}