.fadout {
animation: myfadout 2s linear 0s 1 normal;
-moz-animation: myfadout 2s linear 0s 1 normal;	/* Firefox */
-webkit-animation: myfadout 2s linear 0s 1 normal;	/* Safari 和 Chrome */
-o-animation: myfadout 2s linear 0s 1 normal;	/* Opera */
}


@keyframes myfadout
{
0%   {background-color:black;filter:alpha(opacity=50); -moz-opacity:0.5;opacity:0.5;}
100% {background-color:black;filter:alpha(opacity=0); -moz-opacity:0;opacity:0;}
}

@-moz-keyframes myfadout /* Firefox */
{
0%   {background-color:black;filter:alpha(opacity=50); -moz-opacity:0.5;opacity:0.5;}
100% {background-color:black;filter:alpha(opacity=0); -moz-opacity:0;opacity:0; }
}

@-webkit-keyframes myfadout /* Safari 和 Chrome */
{
0%   {background-color:black;filter:alpha(opacity=50); -moz-opacity:0.5;opacity:0.5;}
100% {background-color:black;filter:alpha(opacity=0); -moz-opacity:0;opacity:0; }
}

@-o-keyframes myfadout /* Opera */
{
0%   {background-color:black;filter:alpha(opacity=50); -moz-opacity:0.5;opacity:0.5;}
100% {background-color:black;filter:alpha(opacity=0); -moz-opacity:0;opacity:0;}
}