html 页面等待效果

<div class="loading">
        <span></span>
        <span></span>
        <span></span>
        <span></span>
        <span></span>
</div>

css

.loading{
            width: 80px;
            height: 40px;
            margin: 0 auto;
            margin-top:100px;
        }
        .loading span{
            display: inline-block;
            width: 8px;
            height: 100%;
            border-radius: 4px;
            background: lightgreen;
            -webkit-animation: load 1s ease infinite;
        }
        @-webkit-keyframes load{
            0%,100%{
                height: 40px;
                background: lightgreen;
            }
            50%{
                height: 70px;
                margin: -15px 0;
                background: lightblue;
            }
        }
        .loading span:nth-child(2){
            -webkit-animation-delay:0.2s;
        }
        .loading span:nth-child(3){
            -webkit-animation-delay:0.4s;
        }
        .loading span:nth-child(4){
            -webkit-animation-delay:0.6s;
        }
        .loading span:nth-child(5){
            -webkit-animation-delay:0.8s;
        }