How to use the css.css function in css

function onAgent(err, agent) {
      if (err) { throw err; }

      if (files["css.css"]) {
        var css = files["css.css"].content;
        var klass = "Z" + (Math.random()* 0x100000000000000).toString(16);
        domContainer.setAttribute("class", klass);
        var scope = domContainer.tagName.toLowerCase() + "." + klass + " ";
        css = css.replace(/\{[^}]*\}/g, function (block) {
          return block.replace(/\s*\n\s*/g, ' ');
        }).split(/\n/).map(function (line) {
          line = line.trim();
          if (!line) return line;
          return scope + line;
        }).join("\n");
        var style = document.createElement('style');
        style.textContent = css;
        delete agent.css;
        document.head.appendChild(style);
      }

function onAgent(err, agent) {
      if (err) { throw err; }

      if (files["css.css"]) {
        var css = files["css.css"].content;
        var klass = "Z" + (Math.random()* 0x100000000000000).toString(16);
        domContainer.setAttribute("class", klass);
        var scope = domContainer.tagName.toLowerCase() + "." + klass + " ";
        css = css.replace(/\{[^}]*\}/g, function (block) {
          return block.replace(/\s*\n\s*/g, ' ');
        }).split(/\n/).map(function (line) {
          line = line.trim();
          if (!line) return line;
          return scope + line;
        }).join("\n");
        var style = document.createElement('style');
        style.textContent = css;
        delete agent.css;
        document.head.appendChild(style);
      }

function onLoad(evt) {
    var files = JSON.parse(req.responseText).files;
    values.css = files["css.css"] && files["css.css"].content;
    values.js = files["js.js"] && files["js.js"].content;
    values.lua = files["lua.lua"] && files["lua.lua"].content;
    window.location.search = "?agent=" + options.agent;
  }

xhr.addEventListener('load', function () {
			try {
				const data = JSON.parse(xhr.responseText);
				if (!(data && data.files && data.files['algo.js'] && data.files['css.css'])) {
					reject(data);
				} else {
					resolve(data);
				}
			} catch (err) {
				reject(err);
			}
		});
		xhr.addEventListener('error', reject);

.then(function (resp) {
				editors.algo.setValue(resp.files['algo.js'].content, -1);
				editors.css.setValue(resp.files['css.css'].content, -1);
				logger.info('loaded algo based on url!');
				loadIndicator.clear();
				setEditState(true);
			})
			.catch(function () {