.backbutton{
    max-width:50px;
}
.navbar-nav > li {
    float: left;
    position: relative;
}
.navbar-light .navbar-nav .active a::after {
    border-bottom: 5px solid #5bc0eb;
    bottom: -10px;
    content: " ";
    left: 0;
    position: absolute;
    right: 0;
    max-width: 30px;
}
.pbfs{
    font-size:1rem
}
.xyz { 
    background-size: auto; 
    text-align: center; 
    padding-top: 100px; 
} 
.btn-circle.btn-sm { 
    width: 30px; 
    height: 30px; 
    padding: 6px 0px; 
    border-radius: 50%; 
    text-align: center; 
} 
.btn-circle.btn-md { 
    width: 50px; 
    height: 50px; 
    padding: 7px 10px; 
    border-radius: 50%; 
    text-align: center; 
}
.btn-circle.btn-md :active{ 
    width: 50px; 
    height: 50px; 
    padding: 7px 10px; 
    border-radius: 50%; 
    text-align: center; 
}
.btn-circle.btn-xl { 
    width: 70px; 
    height: 70px; 
    padding: 10px 16px; 
    border-radius: 50%; 
    text-align: center; 
}