.arrow{width:0;height:0;border:5px solid #000}.arrow-black{border-color:#000}.arrow-white{border-color:#fff}.arrow-up{border-left-color:transparent;border-right-color:transparent;border-top:0 none}.arrow-down{border-left-color:transparent;border-right-color:transparent;border-bottom:0 none}.arrow-right{border-top-color:transparent;border-bottom-color:transparent;border-right:0 none}.arrow-left{border-top-color:transparent;border-bottom-color:transparent;border-left:0 none}