body {
    opacity: 1;
    -webkit-transition:opacity .5s ease-out 0s;
    -moz-transition:opacity .5s ease-out 0s;
    -o-transition:opacity .5s ease-out 0s;
    transition:opacity .5s ease-out 0s}
    
body.fadeout {
    opacity: 0;
    transition: none
}