融合粘滞效果

CSS代码：

body {
    background-color: #000;
    filter: blur(10px) contrast(5);
    padding: 100px;
}
.box {
    width: 100px; height: 100px;
    border-radius: 50%;
    position: absolute;
}
.box-1 {
    background-color: deepskyblue;
    animation: fly-r 5s infinite alternate;
}
.box-2 {
    width: 60px; height: 60px;
    margin-top: 20px;
    background-color: white;
    animation: fly-l 5s infinite alternate;
}
@keyframes fly-r {
    from { transform: translateX(0); }
    to   { transform: translateX(120px); }
}
@keyframes fly-l {
    from { transform: translateX(120px); }
    to   { transform: translateX(0); }
}

HTML代码：

<div class="box box-1"></div>
<div class="box box-2"></div>