1 <!DOCTYPE html>
2 <html >
3 <head>
4 <meta charset="UTF-8">
5 <title>Document</title>
6 <script>
7 window.onload=function(){
8 var arr=[-45,60,-75,90];
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10 box.onclick=function(){
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13 var oH=document.getElementsByTagName('head')[0];
14 var oS=document.createElement('style');
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16 oS.innerHTML=
17 '@keyframes rotate{'+
18 '0%{'+
19 'transform: rotate('+arr[i%4]+'deg);'+
20 '}'+
21 '100%{'+
22 'transform: rotate(-'+arr[i%4]+'deg);'+
23 '}'+
24 '}';
25 box.style.animation='1s rotate linear';
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28 ready=true;
29 document.getElementsByTagName('head')[0].removeChild(oS);
30 },false);
31 console.log(oS.innerHTML);
32 };
33
34 };
35 </script>
36 </head>
37 <body>
38 <div ></div>
39 </body>
40 </html>