css center and fadeIn

HTML

<div class="fadeInRight" style="background:red;height:100%;display:block">as
<div style="background: blue;width:100px;height:200px" class="alignC_VH">
patata
</div>
</div>

CSS

html, body{ width:100%;height:100%; margin:0px;padding:0px;
   overflow:hidden;}
.fadeInRight {
    animation-name: fadeInRight;
        animation-duration: 0.5s;
}


@keyframes fadeInRight {
	0% {
	    opacity: 0;
	    transform: translateX(40px);
	}
	100% {
	    opacity: 1;
	    transform: translateX(0px);
	}
}

.alignC_VH {
	position: absolute;
	left: 50%;
	transform: translate(-50%, 0%);
}