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    var overscroll = function(el) {
	  	el.addEventListener('touchstart', function() {
	    	var top = el.scrollTop
	      	, totalScroll = el.scrollHeight
	    	, currentScroll = top + el.offsetHeight
	    //If we're at the top or the bottom of the containers
	    //scroll, push up or down one pixel.
	    //
	    //this prevents the scroll from "passing through" to
	    //the body.
		    if(top === 0) {
		      el.scrollTop = 1
		    } else if(currentScroll === totalScroll) {
		      el.scrollTop = top - 1
		    }
	    })
	  	el.addEventListener('touchmove', function(evt) {
		    //if the content is actually scrollable, i.e. the content is long enough
		    //that scrolling can occur
		    if(el.offsetHeight < el.scrollHeight)
		      evt._isScroller = true
		})
	}
	overscroll(document.querySelector('.outer'));
	document.body.addEventListener('touchmove', function(evt) {
		//In this case, the default behavior is scrolling the body, which
		//would result in an overflow.  Since we don't want that, we preventDefault.
		if(!evt._isScroller) {
		  evt.preventDefault()
		}
	})    var overscroll = function(el) {