function fontsizeup() {
	if(document.body.style.zoom) {
		var cursize = parseInt(document.body.style.zoom);
	}
	else {
		var cursize = 100;
	}		
	
	if(cursize < 400) {
		cursize = cursize + 25;
	}
	
	document.body.style.zoom = cursize+"%";
	document.getElementById("hidden_f").src="set_env.php?ZOOM="+cursize;
}

function fontsizedown() {
	if(document.body.style.zoom) {
		var cursize = parseInt(document.body.style.zoom);
	}
	else {
		var cursize = 100;
	}		
	
	if(cursize > 100) {
		cursize = cursize - 25;
	}
	
	document.body.style.zoom = cursize+"%";
	document.getElementById("hidden_f").src="set_env.php?ZOOM="+cursize;
}