paolochiodi/addCssClass.js

## addCssClass.js
(function(){

  var newStylesheet = null;

  window.addCssClass = function (selector, content){
    // ensure presence of head element
    if(typeof selector === 'string'){

      console.log('creating');

      if(!newStylesheet){

        var headElement = document.getElementsByTagName('head');

        if(!headElement.length){

          var htmlElement = document.getElementsByTagName('html');
          if(htmlElement.length === 0) return;
          htmlElement = htmlElement[0];

          headElement = document.createElement('head');
          htmlElement.insertChild(headElement, htmlElement.firstChild);

        }else{
          headElement = headElement[0];
        }

        var styleElement = document.createElement("style");
        styleElement.type = "text/css";

        // add to <head>
        headElement.appendChild(styleElement);

        if(document.styleSheets){
          var sss = document.styleSheets;
          newStylesheet = sss[sss.length - 1];
        }
      }

      if(newStylesheet){
        // stringify content
        var style = stringify(content),
            rules = (newStylesheet.cssRules || newStylesheet.rules);

        if(newStylesheet.insertRule){
          newStylesheet.insertRule(selector + '{' + style + '}', rules.length);
        }else if(newStylesheet.addRule){
          newStylesheet.addRule(selector, style)
        }
        return rules[rules.length - 1];
      }
    }else{

      // stringify content
      selector.style.cssText = stringify(content);
      return selector;
    }
  }

  function stringify(obj){
    var style = '';

    for(var attribute in obj){
      style += attribute + ':' + obj[attribute] + ';';
    }

    return style
  }

})();
	(function(){

	var newStylesheet = null;

	window.addCssClass = function (selector, content){
	// ensure presence of head element
	if(typeof selector === 'string'){

	console.log('creating');

	if(!newStylesheet){

	var headElement = document.getElementsByTagName('head');

	if(!headElement.length){

	var htmlElement = document.getElementsByTagName('html');
	if(htmlElement.length === 0) return;
	htmlElement = htmlElement[0];

	headElement = document.createElement('head');
	htmlElement.insertChild(headElement, htmlElement.firstChild);

	}else{
	headElement = headElement[0];
	}

	var styleElement = document.createElement("style");
	styleElement.type = "text/css";

	// add to <head>
	headElement.appendChild(styleElement);

	if(document.styleSheets){
	var sss = document.styleSheets;
	newStylesheet = sss[sss.length - 1];
	}
	}

	if(newStylesheet){
	// stringify content
	var style = stringify(content),
	rules = (newStylesheet.cssRules \|\| newStylesheet.rules);

	if(newStylesheet.insertRule){
	newStylesheet.insertRule(selector + '{' + style + '}', rules.length);
	}else if(newStylesheet.addRule){
	newStylesheet.addRule(selector, style)
	}
	return rules[rules.length - 1];
	}
	}else{

	// stringify content
	selector.style.cssText = stringify(content);
	return selector;
	}
	}

	function stringify(obj){
	var style = '';

	for(var attribute in obj){
	style += attribute + ':' + obj[attribute] + ';';
	}

	return style
	}

	})();