backtotop tablet

gistfile1.txt

document.addEventListener("touchmove", ScrollStart, false);
document.addEventListener("scroll", Scroll, false);
document.addEventListener("touchcancel", Scroll, false);

function ScrollStart() {
    //hide back to top button now if it exists
}

function Scroll() {
    //show back to top button now if scroll far enough
}

-webkit-animation: fadein 2s; /* Safari and Chrome */
   -moz-animation: fadein 2s; /* Firefox */
    -ms-animation: fadein 2s; /* Internet Explorer */
     -o-animation: fadein 2s; /* Opera */
        animation: fadein 2s;

}

@Keyframes fadein {
from { opacity: 0; }
to { opacity: 1; }
}

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

/* Safari and Chrome */
@-webkit-keyframes fadein {
from { opacity: 0; }
to { opacity: 1; }
}

/* Internet Explorer */
@-ms-keyframes fadein {
from { opacity: 0; }
to { opacity: 1; }
}​

Guide for css animation:
http://css-tricks.com/snippets/css/keyframe-animation-syntax/