纯css实现乌云密布的天气图标效果

<div class="container">
    <div class="cloudy"></div>
</div>

body{
    background: rgba(73, 74, 95, 1);
}
.container{
    width: 170px;
    height: 170px;
    position: relative;
    margin: 250px auto;
}

.cloudy{
    width: 50px;
    height: 50px;
    position: absolute;
    top: 70px;
    left: 80px;
    margin-left: -60px;
    background: #ccc;
    border-radius: 50%;
    box-shadow: #ccc 65px -10px 0 -5px,
        #ccc 25px -25px,
        #ccc 30px 10px,
        #ccc 60px 15px  0 -10px,
        #ccc 85px 5px 0 -5px;
    animation: cloudy 5s ease-in-out infinite;
}
@keyframes cloudy{
    50%{
        transform: translateY(-20px);
    }
}

.cloudy::after{
    content: '';
    width: 120px;
    height: 15px;
    position: absolute;
    bottom: -60px;
    left: 5px;
    background: #000;
    border-radius: 50%;
    opacity: 0.2;
    animation: cloudy-shadow 5s ease-in-out infinite;
    transform: scale(0.7);
}

@keyframes cloudy-shadow{
    50%{
        transform: translateY(20px) scale(1);
        opacity: 0.05;
    }
}