/**
 * Documento pronto
 */
$(function(){

	setHeight();
	
	$(window).resize(function(){
		setHeight();
	});
});

/**
 * Seta altura do conteudo principal
 *
 * @return void
 */
function setHeight()
{
	var windowHeight = $(window).height();
	
	var topHeight = $("#top").outerHeight();
	var botHeight = $("#bot").outerHeight();
	var midHeight = $("#mid").outerHeight();
	
	var sum = topHeight + botHeight;
	
	if (sum + midHeight <= windowHeight) {
		$("#mid").height(windowHeight - sum - 50);
	}
};