.ou_fixFoot4 {
    display: block;
    width: 100%;
    max-width: 640px;
    position: fixed;
    bottom: 0;
    /* background-color: #fff; */
    /* border-top: solid 1px #E1E1E1; */

    left: 50%;
    z-index: 999;
    /* -webkit-transition: all .7s ease-out;
                    transition: all .7s ease-out; */
    -webkit-transform: translate(-50%, 0);
    transform: translate(-50%, 0);
}

.ou_box {
    /* padding: 0; */
    margin: 0 auto;
    width: 100%;
    max-width: 640px;
    min-width: 320px;
}

#bodyBottom4 {
    margin-bottom: 49px;
    height: 0;
}

.ou_channel4 {
    box-sizing: border-box;
    display: inline-block;
    position: relative;
    vertical-align: top;
    float: left;
    width: 25%;
    line-height: 0;
}

.ou_channel4 img {
    width: 100%;
}