Silk browser background cover center doesn't work if there is a div absolute

Question

body.page-id-444 {
    height: 100%;
    margin:0px;

background: url(picture) ; 
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-position: center; 
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
     background-size: cover;
}

.page-id-444 div#page {
   width: 500px;
   height: 450px;
   top: 0;
   bottom: 0;
   position: absolute;
   left :0;
   right: 0;}
}

On Fire HD 8 in Landscape mode , the background goes up(no in the center) , if I remove from div#page position: absolute; then the background goes in center.

Any suggestions?