pre{
    font-size: 20px;
}
hr{
    border-bottom: 2px solid #fff;
}
.ans{
    color:brown;
    font-size: 20px;
    font-weight: bold;
    display: none;
}
.sans{
     color:forestgreen;
    font-size: 20px;
    font-weight: bold;
}
#programming li{
    font-size:26px;
}
 .btn-success{
            background-color:#65af3e;
            color:white;
        }