h5向上翻页图标晃动动画，css固定h5向上翻页图标在页面上

//html结构
<div class='upImg'><div>

//css
.upImg {
background-image: url(../images/01.png);
position: fixed;
background-repeat: no-repeat;
background-position: center;
background-size: cover;
z-index: 11;
width: 6.5625%;
height: 0;
padding-bottom: 4.063%;
left: 50%;
-webkit-transform: translate(-50%, 0);
-ms-transform: translate(-50%, 0);
transform: translate(-50%, 0);
bottom: 42px;
-webkit-animation: upDown_anim 2s ease-in-out infinite;
animation: upDown_anim 2s ease-in-out infinite;
}
@-webkit-keyframes upDown_anim {
0%,
100% {
-webkit-transform: translate(0, 0);
transform: translate(0, 0);
}
50% {
-webkit-transform: translate(0, 20px);
transform: translate(0, 20px);
}
}
@keyframes upDown_anim {
0%,
100% {
-webkit-transform: translate(0, 0);
transform: translate(0, 0);
}
50% {
-webkit-transform: translate(0, 20px);
transform: translate(0, 20px);
}
}