vue 首屏添加加载动画 loading

    <div id="app">
      <div id="Loading">
        <div class="loader-inner ball-beat">
          <div></div>
          <div></div>
          <div></div>
        </div>
      </div>
    </div>
 
    <style type="text/css">
      #Loading {
        top: 50%;
        left: 50%;
        position: absolute;
        -webkit-transform: translateY(-50%) translateX(-50%);
        transform: translateY(-50%) translateX(-50%);
        z-index: 100;
      }
 
      @-webkit-keyframes ball-beat {
        50% {
          opacity: 0.2;
          -webkit-transform: scale(0.75);
          transform: scale(0.75);
        }
 
        100% {
          opacity: 1;
          -webkit-transform: scale(1);
          transform: scale(1);
        }
      }
 
      @keyframes ball-beat {
        50% {
          opacity: 0.2;
          -webkit-transform: scale(0.75);
          transform: scale(0.75);
        }
 
        100% {
          opacity: 1;
          -webkit-transform: scale(1);
          transform: scale(1);
        }
      }
 
      .ball-beat > div {
        background-color: #4999ff;
        width: 10px;
        height: 10px;
        border-radius: 100% !important;
        margin: 2px;
        -webkit-animation-fill-mode: both;
        animation-fill-mode: both;
        display: inline-block;
        -webkit-animation: ball-beat 0.7s 0s infinite linear;
        animation: ball-beat 0.7s 0s infinite linear;
      }
 
      .ball-beat > div:nth-child(2n-1) {
        -webkit-animation-delay: 0.35s !important;
        animation-delay: 0.35s !important;
      }
    </style>