function setActiveStyleSheet(title) {
    var i, a, main;
    var listo = 0;
    for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
        if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
            a.disabled = true;
            if(a.getAttribute("title") == title){
                listo = 1;
                a.disabled = false;
            }
        }
    }
    if(listo == 0) {
    	document.getElementsByTagName("link")[0].disabled = false;
    }
}

function getActiveStyleSheet() {
    var i, a;
    for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
        if(a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title") && !a.disabled) {
			//alert(a.getAttribute("title"));
			return a.getAttribute("title");
		  }
    }
    return null;
}

function getPreferredStyleSheet() {
    var i, a;
    for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
        if(a.getAttribute("rel").indexOf("style") != -1
           && a.getAttribute("rel").indexOf("alt") == -1
           && a.getAttribute("title")
        ) return a.getAttribute("title");
    }
    return null;
}

function createCookie(name,value,days) {
    if (days) {
        var date = new Date();
        date.setTime(date.getTime()+(days*24*60*60*1000));
        var expires = "; expires="+date.toGMTString();
    }
    else expires = "";
    document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for(var i=0;i < ca.length;i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1,c.length);
        if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
    }
    return null;
}


window.addEvent('unload', function() {
    var title = getActiveStyleSheet();
    createCookie("style", title, 365);
})

function estiloMenos() {
    var estiloActual = getActiveStyleSheet();
    //alert(estiloActual)
    numEstiloActual = (estiloActual.substring(5,6)*1);
    if (numEstiloActual>0){
        numEstilo = numEstiloActual - 1;
        nombreEstilo ="style" + numEstilo;        
        setActiveStyleSheet(nombreEstilo, 1);
    }   
}

function estiloMas() {
    var estiloActual = getActiveStyleSheet();
    //alert(estiloActual)
    numEstiloActual = (estiloActual.substring(5,6) * 1);
    if (numEstiloActual<3){
        numEstilo = numEstiloActual + 1;
        nombreEstilo ="style" + numEstilo;        
        setActiveStyleSheet(nombreEstilo, 1);
    }
}