CSS3实现的文字弹出特效

<div></div> 
<div> 
  <span>https://www.jb51.net</span>
</div>


<p>a css3 animation demo</p>

@import url('https://fonts.googleapis.com/css?family=roboto:300');

body {
  text-align:center;
  background:linear-gradient(141deg, #ccc 25%, #eee 40%, #ddd 55%);
  color:#555;
  font-family:'roboto';
  font-weight:300;
  font-size:32px;
  padding-top:40vh;
  height:100vh;
  overflow:hidden;
  -webkit-backface-visibility: hidden;
  -webkit-perspective: 1000;
  -webkit-transform: translate3d(0,0,0);
}

div {
  display:inline-block;
  overflow:hidden;
  white-space:nowrap;
}

div:first-of-type {    /* for increasing performance 
                       id/class should've been used. 
                       for a small demo 
                       it's okaish for now */
  animation: showup 7s infinite;
}

div:last-of-type {
  width:0px;
  animation: reveal 7s infinite;
}

div:last-of-type span {
  margin-left:-355px;
  animation: slidein 7s infinite;
}

@keyframes showup {
    0% {opacity:0;}
    20% {opacity:1;}
    80% {opacity:1;}
    100% {opacity:0;}
}

@keyframes slidein {
    0% { margin-left:-800px; }
    20% { margin-left:-800px; }
    35% { margin-left:0px; }
    100% { margin-left:0px; }
}

@keyframes reveal {
    0% {opacity:0;width:0px;}
    20% {opacity:1;width:0px;}
    30% {width:355px;}
    80% {opacity:1;}
    100% {opacity:0;width:355px;}
}


p {
  font-size:12px;
  color:#999;
  margin-top:200px;
}