没事闲的做了一个简单的loading动画 js就几行，却出了问题。。chrome下成功，但在Firefox下怎么改都显示不出来。。
提示window.event is not defined，在网上搜到了解决办法。原来FF跟不支持IE的JS标准，chrome却跟IE混的，太没节操了。 代码不支持IE因为这个动画是CSS3的。

DEMO:Loading Demo

HTML:

CSS:

#loading{
display:none; 

width:70px; 

position:fixed; 

top:50%; 

left:50%; 

margin-left:-40px; 

}
 .blockG{ background-color:#FFFFFF;
 border:3px solid #8896fa; 
float:left; height:50px; 

margin-left:7px; width:10px; 

opacity:0.1; 

-moz-animation-name:bounceG; 
-moz-animation-duration:1s; 
-moz-animation-iteration-count:infinite;
 -moz-animation-direction:linear;
 -moz-transform:scale(0.7); 
-webkit-animation-name:bounceG; 
-webkit-animation-duration:1s;
 -webkit-animation-iteration-count:infinite; 
-webkit-animation-direction:linear; 
-webkit-transform:scale(0.7);
 -ms-animation-name:bounceG;
 -ms-animation-duration:1s;
 -ms-animation-iteration-count:infinite;
 -ms-animation-direction:linear;
 -ms-transform:scale(0.7); 
-o-animation-name:bounceG;
 -o-animation-duration:1s; 
-o-animation-iteration-count:infinite; 
-o-animation-direction:linear; 
-o-transform:scale(0.7);
 animation-name:bounceG; 
animation-duration:1s; 

animation-iteration-count:infinite; 

animation-direction:linear; 

 transform:scale(0.7); }
 #blockG1{ -moz-animation-delay:0.39s; 
-webkit-animation-delay:0.39s;
 -ms-animation-delay:0.39s; 
-o-animation-delay:0.39s;
 animation-delay:0.39s; }
 #blockG2{ -moz-animation-delay:0.52s;
 -webkit-animation-delay:0.52s;
 -ms-animation-delay:0.52s; 
-o-animation-delay:0.52s; 
animation-delay:0.52s; } 


blockG_3{ -moz-animation-delay:0.65s;

-webkit-animation-delay:0.65s; 
-ms-animation-delay:0.65s; 
-o-animation-delay:0.65s; 
animation-delay:0.65s; } 

 @-moz-keyframes bounceG{
 0%{ -moz-transform:scale(1.2); opacity:1} 
100%{ -moz-transform:scale(0.7); opacity:0.1} } 

@-webkit-keyframes bounceG{ 
0%{ -webkit-transform:scale(1.2); opacity:1} 

100%{ -webkit-transform:scale(0.7); opacity:0.1} } 

 @-ms-keyframes bounceG{
 0%{ -ms-transform:scale(1.2); opacity:1}
 100%{ -ms-transform:scale(0.7); opacity:0.1} }
 @-o-keyframes bounceG{ 
0%{ -o-transform:scale(1.2); opacity:1} 

100%{ -o-transform:scale(0.7); opacity:0.1} } 

@keyframes bounceG{
0%{ transform:scale(1.2); opacity:1} 

 100%{ transform:scale(0.7); opacity:0.1} }

JS:

document.onclick = function(e)
{
src = e.target || window.event.srcElement; 

if (src.tagName=="A") 

{
document.getElementById('loading').style.display="block"; 

setTimeout("document.getElementById('loading').style.display='none'",3000); 

}
}