var text_size_step = 20;

function text_size(percent)
{
	if ($('contenedor_textsize'))
	{
		if (document.getElementById("contenedor_textsize").style.fontSize == "")
			document.getElementById("contenedor_textsize").style.fontSize = "100%";
		
		var numpercent = document.getElementById("contenedor_textsize").style.fontSize.substring(0,3);
		
		if (percent == 0)
			document.getElementById("contenedor_textsize").style.fontSize = "100%";
		else if ((percent + parseInt(numpercent)) <= 140 && (percent + parseInt(numpercent)) >= 100)
			document.getElementById("contenedor_textsize").style.fontSize = (percent + parseInt(numpercent)) + '%';
	}
}

function reset_text_size()
{
	text_size(0);
}

function increment_text_size()
{
	text_size(+text_size_step);
}

function decrement_text_size()
{
	text_size(-text_size_step);
}

Event.observe(window, 'load', function initializeTextSizeEvents()
{
	if ($('tamano_texto')) $('tamano_texto').observe('click', reset_text_size);
	if ($('tamano_texto_mas')) $('tamano_texto_mas').observe('click', increment_text_size);
	if ($('tamano_texto_menos')) $('tamano_texto_menos').observe('click', decrement_text_size);
});