function show_block(show_id, hide_id)
{
	var show_div = document.getElementById(show_id);
	show_div.style.display = "block";
	
	var hide_div = document.getElementById(hide_id);
	hide_div.style.display = "none";
}

function replace_image(big_id, new_source)
{
	var big = document.getElementById(big_id);
	
	big.style.backgroundImage = 'url(' + new_source + ')';
}