body {
    background-color: rgba(240,240,240,1.00);
    color: green;
}

/* Style the header */
header {
    background-color: rgb(240, 240, 240);
    padding: 30px;
    text-align: center;
    font-size: 35px;
    color: black;
}

h2 {
    font-size: 14px;
}

hr {
    margin-top: 1rem;
    margin-bottom: 1rem;
    border: 0;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

#nav1
{  
    background-color:#888; /*whichever you want*/
    opacity: 0.95; 
    filter:(opacity=95);
    font-size: large;     
}