CSS background color keyframes animation

问题:

I'm trying to animate a simple fade in/out for a toolbar background color in firefox (themeing). Problem is, my color fades completely out to transparent. I would prefer my color to fade about half way then start easing back to full color.

I listed the code I've tried...

toolbar{
    animation-name: animation;
    animation-duration: 5s;
    animation-timing-function: ease-in-out;
    animation-iteration-count: infinite;    
    animation-play-state: running;
}

@keyframes animation {
    50.0%  {background-color:red;}
}

I've tried fiddling around with opacity settings with no luck. Any help is appreciated.

回答1:

@-webkit-keyframes animation {
    0%     {background-color:red;}
    50.0%  {background-color:#ff6666;} /* your chosen 'mid' color */
    100.0%  {background-color:red;}
}

@keyframes animation {
    0%     {background-color:red;}
    50.0%  {background-color:#ff6666;}
    100.0%  {background-color:red;}
}

JSfiddle Demo