CSS Animations not working in Firefox - pseudo

Question

I have some CSS animations that will not work in Firefox. They are applied to a pseudo element (:after) and all work fine in every other browser.

The animations are applied here

:after
{
    display:block;
    background:url('../img/snow.png'), url('../img/snow2.png') ;
    -webkit-animation: snow 15s linear infinite;
    -moz-animation: snow 15s linear infinite;
    -ms-animation: snow 15s linear infinite;
    animation-name:snow;
    animation-duration:15s;
    animation-timing-function:linear;
    height:500px;
    width:100%;
    content:'';
    position:absolute;
    top:0;
    left:0;
}

And the animations themselves are here:

@-webkit-keyframes snow {
 0% {background-position: 0px 0px;}
 100% {background-position: 0px 1000px, 0 500px;}
}
@keyframes snow {
 0% {background-position: 0px 0px;}
 100% {background-position: 0px 1000px, 0 500px;}
}

@-moz-keyframes snow {
 0% {background-position: 0px 0px;}
 100% {background-position: 0px 1000px, 0 500px;}
}
@-ms-keyframes snow {
 0% {background-position: 0px 0px;}
 100% {background-position: 0px 1000px, 0 500px;}
}

Any help or advice would be greatly appreicated!

Answer 1

Your issue is that your keyframes have different-length lists for background-position. It looks like Gecko doesn't allow interpolation between different-length background-position lists. I filed https://bugzilla.mozilla.org/show_bug.cgi?id=945600

In the meantime, simply using

0% {background-position: 0px 0px, 0px 0px;}

in your keyframes should make this work, I believe.

Answer 2

有时，如果您打开了萤火虫或其他任何Web开发人员工具都已打开，则CSS无法正常工作。