Option for Excluding Comments Section, Fix for Responsive Design Issues

I suppose this is more of a feature request, but this code also helped solve an issue for me.

The theme I am using has responsive design, and when I was looking at my site on a small device, the bar was calculating incorrectly (by not being completely full even when at the very end of the document). I was also looking to exclude my comments section from being calculated in the document length, and this is what I came up with that solves both of those issues, by using the post class instead of using the entire document in the getMax(); function:

reading-position-indicator/scripts/iworks_position.js, lines 15-17:

	var getMax = function(){
		return $(".post").height() - $(window).height();
	}

I suppose there is probably a way to make it include the comments as well, by selecting the right <div>? (maybe .single-wrapper?) It might come down to personal preference, but perhaps you could add those as options.

Thanks for this amazing plugin! The rest of it works fantastically.

Cheers!

https://ww.wp.xz.cn/plugins/reading-position-indicator/