* {
    box-sizing: border-box;
}

body {
    background: #02213d url("../img/Home.jpg") no-repeat 0 0 / 100%;
    overflow-x: hidden;
}

.flex {
    display: flex;
    justify-content: flex-start;
    align-items: center;
}

img {
    -webkit-touch-callout: none;
}

.relative {
    position: relative;
}

.absolute {
    position: absolute;
}

.center {
    text-align: center;
}

.empty {
    padding: 1em;
    text-align: center;
}

.back {
    background: url(//starcdn.mengliaoba.cn/starface/yy/pk1v1_2109/rts.png) no-repeat left center / 90%;
    height: 69px;
    width: 40px;
    position: absolute;
    top: 0;
    left: 5px;
    z-index: 100;
}