jquery-mobile/css/structure/jquery.mobile.transitions.fade.css

@-webkit-keyframes fadein {
    from { opacity: 0; }
    to { opacity: 1; }
}

@-moz-keyframes fadein {
    from { opacity: 0; }
    to { opacity: 1; }
}

@-webkit-keyframes fadeout {
    from { opacity: 1; }
    to { opacity: 0; }
}

@-moz-keyframes fadeout {
    from { opacity: 1; }
    to { opacity: 0; }
}

.fade.out {
	opacity: 0;
	-webkit-animation-duration: 125ms;
	-webkit-animation-name: fadeout;
	-moz-animation-duration: 125ms;
	-moz-animation-name: fadeout;
}

.fade.in {
	opacity: 1;
	-webkit-animation-duration: 225ms;
	-webkit-animation-name: fadein;
	-moz-animation-duration: 225ms;
	-moz-animation-name: fadein;
}