prova così
codice:
function elenca_rules()
{
var styles = document.styleSheets;
if(!styles) return;
var n = styles.length; //1 foglio di stile
var stile = styles[0];
var rules = (stile.rules)? stile.rules : stile.cssRules;//IE, altri
if(!rules) return;
var nrs = rules.length;
var txt = "<table rules=\"rows\" style='border-collapse: collapse;'>";
for(var i = 0; i < nrs; i++)
{
var rule = rules[i];
var cssText = (rule.style.cssText)? rule.style.cssText : rule.cssText//IE, altri
txt += "<tr>"
+ "<td valign='top'>" + i + "</td><td>" + cssText + "</td>"
+ "</tr>";
}
txt += "</table>";
document.getElementById("div1").innerHTML = txt;
}