Today you will learn how to add an arrow in boostrap menu because Twitter bootstrap has no class to an arrow in activated tab or page in menu. So i have written a simple class for all of you to putt an arrow in your bootstrap menu.




This is simple class just copy and paste in your custom class.
#main_menu.navbar-default .navbar-nav > .active > a:after {
content: "";
position: absolute;
bottom: -10px;
left: 45%;
border-width: 0px 5px 5px;
border-style: solid;
border-color: #c32033 transparent;
display: block;
width: 0;
}