code: function(content) {
  			var root = new CSSSection(null, content);
  			var rules = this.findAllRules(content);
  
  			// rules are sorted in order they appear in CSS source
  			// so we can optimize their nesting routine
  			var insert = function(range, ctx) {
  				while (ctx && ctx.range) {
  					if (ctx.range.contains(range)) {
  						return ctx.addChild(range);
  					}
  
  					ctx = ctx.parent;
  				}
  
  				// if we are here then given range is a top-level section
  				return root.addChild(range);
  			};
  
  			var ctx = root;
  			rules.forEach(function(r) {
  				ctx = insert(r, ctx);
  			});
  
  			return root;
  		}
docs: Parses and returns all sections in given CSS
  as tree-like structure, e.g. provides nesting
  info
  @param  {String} content CSS content
  @return {CSSSection}