body{
    background-color: #003366;
}
header,div:not(#out){
    border-radius: 5px;
    padding: 10px;
    margin: 5px;
    background-color: white;
}
button{
    background-color: white;
    border-radius: 25px;
}
nav{
    background-color: white;
    padding: 10px;
    margin: 5px;
    border-radius: 5px;
    position: -webkit-sticky; /* Safari */
    position: sticky;
    top:0;
    bottom: 0;
}
#out a{
    color: white;
}
nav:hover,header:hover,div:hover:not(#out){
    background-color: #0080ff !important;
    color:white;
}
div:hover a,nav:hover a{
    color:white; 
}
@media screen and ( min-width : 800px)
{
    body{
        display: grid;
        grid-template-columns: 250px auto ;
    }
    header{
        grid-column: 1/3;
    }
    div{
        grid-column: 1/3;
    }
    nav{
        grid-column: 1;
        grid-row: 2;
    }
    
}