button{

        display:none;

        width:$rem*45;

        height:$rem*33;

        //我这里Android 4.4.3 hack 写法

        height:calc(1/16*32px);

        font-size:$rem*12;

        background-color:#b41a1a;

        border:1px solid #fff;

        color:#fff;

        padding:$rem*10 0;

        position:absolute;

        right:;

        top:;

        border-bottom-right-radius: 4px;

        border-top-right-radius: 4px;

    }