51help具 V2

码：

<!DOCTYPE html>
<html>
<head>
<style> 
div
{
width:100px;
height:100px;
background:red;
position:relative;
animation-name:myfirst;
animation-duration:5s;
animation-timing-function:linear;
animation-delay:2s;
animation-iteration-count:infinite;
animation-direction:alternate;
animation-play-state:running;
/* Firefox: */
-moz-animation-name:myfirst;
-moz-animation-duration:5s;
-moz-animation-timing-function:linear;
-moz-animation-delay:2s;
-moz-animation-iteration-count:infinite;
-moz-animation-direction:alternate;
-moz-animation-play-state:running;
/* Safari and Chrome: */
-webkit-animation-name:myfirst;
-webkit-animation-duration:5s;
-webkit-animation-timing-function:linear;
-webkit-animation-delay:2s;
-webkit-animation-iteration-count:infinite;
-webkit-animation-direction:alternate;
-webkit-animation-play-state:running;
/* Opera: */
-o-animation-name:myfirst;
-o-animation-duration:5s;
-o-animation-timing-function:linear;
-o-animation-delay:2s;
-o-animation-iteration-count:infinite;
-o-animation-direction:alternate;
-o-animation-play-state:running;
}

@keyframes myfirst
{
0%   {background:red; left:0px; top:0px;}
25%  {background:yellow; left:200px; top:0px;}
50%  {background:blue; left:200px; top:200px;}
75%  {background:green; left:0px; top:200px;}
100% {background:red; left:0px; top:0px;}
}

@-moz-keyframes myfirst /* Firefox */
{
0%   {background:red; left:0px; top:0px;}
25%  {background:yellow; left:200px; top:0px;}
50%  {background:blue; left:200px; top:200px;}
75%  {background:green; left:0px; top:200px;}
100% {background:red; left:0px; top:0px;}
}

@-webkit-keyframes myfirst /* Safari and Chrome */
{
0%   {background:red; left:0px; top:0px;}
25%  {background:yellow; left:200px; top:0px;}
50%  {background:blue; left:200px; top:200px;}
75%  {background:green; left:0px; top:200px;}
100% {background:red; left:0px; top:0px;}
}

@-o-keyframes myfirst /* Opera */
{
0%   {background:red; left:0px; top:0px;}
25%  {background:yellow; left:200px; top:0px;}
50%  {background:blue; left:200px; top:200px;}
75%  {background:green; left:0px; top:200px;}
100% {background:red; left:0px; top:0px;}
}
</style>
</head>
<body>

<p><b>注释：</b>本例在 Internet Explorer 中无效。</p>

</body>
</html>

51help TIY

码：

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