CSS Arrow Left

HTML

<a href=""><div class="arrow"></div></a>

CSS

.arrow {
    width:0px;
    height:0px;
    left:100px;
    top:200px;
    position:relative;
    }
.arrow:after,
.arrow:before {
    bottom:0%;
    left:0%;
    border:solid transparent;
    content:" ";
    height:0;
    width:0;
    position:absolute;
}
.arrow:after {
    bottom:3px;
    left:3px;
    border-right-color:#fff;
    border-width:50px;
    margin-left:-50px;
}
.arrow:before {
    border-right-color:#20204d;
    border-width:53px;
    margin-left:-53px;
    top:
}