.button.drodown::after {
    display: block;
    width: 0;
    height: 0;
    border: inset 0.4em;
    content: "";
    border-bottom-width: 0;
    bordr-top-style: solid;
    border-color: #fefefe transparent transparent;
    position: relative;
    top: 0.4em;
    display: inline-block;
    float: right;
    margin-left: 1em;