Récupérer toutes les feuilles de styles CSS d'une page en JS

var css = [];
for (var i=0; i<document.styleSheets.length; i++)
{
    var sheet = document.styleSheets[i];
    var rules = ('cssRules' in sheet)? sheet.cssRules : sheet.rules;
    if (rules)
    {
        css.push('\n/* Stylesheet : '+(sheet.href||'[inline styles]')+' */');
        for (var j=0; j<rules.length; j++)
        {
            var rule = rules[j];
            if ('cssText' in rule)
                css.push(rule.cssText);
            else
                css.push(rule.selectorText+' {\n'+rule.style.cssText+'\n}\n');
        }
    }
}
var cssInline = css.join('\n')+'\n';
cssInline;