CSS Triangle Box Arrow

by ConnorM

HTML

<div id="box"></div>

CSS

#box{
    margin:100px;
    width:200px;
    height:100px;
    border:1px solid #999;
    position:relative;
}

#box:after{
    content:'';
    width:20px;
    height:20px;
    border:1px solid #999;
    border-left:none;
    border-bottom:none;
    position:absolute;
    top:-11px;
    right:10px;
    background:white;
    transform:rotate(-45deg);
    -webkit-transform:rotate(-45deg);
}