Need help with scrolling divs with mouse and UI arrows

If you take a look at this page:

http://174.121.8.194/~unab/practice/special-medical-needs-shelter/

You'll notice that if you hover your mouse over the post content that you can scroll through it. You'll also notice the arrows just to the bottom-right of the post content. The arrows are currently non-functional but the client wants them to be able to be used to scroll through the content along with the mouse. Previously I thought they just wanted the arrows and no mouse scrolling so I found this piece of javascript to do that...

Scrolling post content var total = $("#inner").outerHeight(); var step = 15; function scrollUpFunction() { if(parseInt($("#inner").css('marginTop')) >= -(total)+20) { $("#inner").css('marginTop', parseInt($("#inner").css('marginTop'))-step); $("#down").css('color', '#9a9a9a');
} else { $("#up").css('color', 'red'); } } function scrollDownFunction() { if(parseInt($("#inner").css('marginTop')) <= 0) {
$("#inner").css('marginTop', parseInt($("#inner").css('marginTop'))+step); $("#up").css('color', '#9a9a9a');
} else { $("#down").css('color', 'red'); } } $("#down").mousedown(function() { scrollUpInt = setInterval(scrollUpFunction, 100); }).mouseup(function() { clearInterval(scrollUpInt); }); $("#up").mousedown(function() { scrollDownInt = setInterval(scrollDownFunction, 100); }).mouseup(function() { clearInterval(scrollDownInt); });

Since they want both the mouse and the arrows to scroll the content, is there a way I can edit this code to make it work? Right now you'll notice it scrolls the margin (which hides the content)... but that's problematic for obvious reasons when scrolling with the mouse as well.