.wk-close {
    margin: 0;
    border: 1px solid #000000;
    font: inherit;
    color: inherit;
    padding: 0;
    background: 0 0;
    display: inline-block;
    box-sizing: content-box;
    width: 40px;
    line-height: 40px;
    vertical-align: middle;
    opacity: .3;
}