var max_size = 20;
var min_size = 10;
var default_size = 13;
var current_size = 13;

$( document ).ready( function(){

	$('.increase-size').click(function(){
		if( current_size < max_size) current_size++;
		set_size(current_size);
		
		return false;
	});
	
	$('.reset-size').click(function(){
		set_size(default_size);
		return false;
	});
	
	$('.decrease-size').click(function(){
		if( current_size > min_size) current_size--;
		set_size(current_size);
		
		return false;
	});
});

function set_size( new_size ) {
	$('.text').css({ 'font-size' : new_size + 'px' });
	
	current_size = new_size;
}