.hidden>div {
       display:none;
}

.visible>div {
       display:block;
}

div[id^='grad_opt_']
{
       display:inline-table;
}

#grade{
       display:inline-table;
       width:15%;
}

#cot{
       position:relative;
       margin-bottom:50px;
       margin-top:10%;
}