CSS3 按鈕 打鉤

css:

 /*打鉤 */

        .u-icon-radioSB
        {
            width: 22px;
            height: 22px;
            border-radius: 100%;
            position: relative;
            background: #4288E3;
        }

       .u-icon-radioSB::after
        {
            position: absolute;
           top: 2px;
           left: 7px;
           width: 6px;
           height: 12px;
            border-style: solid;
            border-color: #fff;
            border-width: 0 2px 2px 0;
            -webkit-transform: rotateZ(45deg);
            content: "";
        }

HTML

<span class="u-icon-radioSB"></span>