code: function buildJsFileContent(lines) {
      var ls = lines
          .map(l => l
              // remove space at beginning of line
              .replace(/^\s*/g, "")
              // remove space at end of line
              .replace(/\s*$/g, "")
              // convert \ to \\
              .replace(/\\/g, "\\\\")
              // convert " to \"
              .replace(/"/g, "\\\"")
              // convert " { " to "{"
              .replace(/\s*\{\s*/g, "{")
              // convert " : " to ":"
              .replace(/\s*:\s*/g, ":"))
          .join("")
          // remove comments
          .replace(/\/\*.+?\*\//g, "");
  
      return [
          // add css string
          `var css = "${ls}";`,
          "var enabled = false;",
          "",
          // add function which injects css into page
          "function enable () {",
          "\tif (enabled) return;",
          "\tenabled = true;",
          "",
          "\tvar el = document.createElement('style');",
          "\tel.innerHTML = css;",
          "",
          "\tvar parent = document.head || document.body;",
          "\tparent.firstChild ?",
          "\t\tparent.insertBefore(el, parent.firstChild) :",
          "\t\tparent.appendChild(el);",
          "}",
          "",
          "export {",
          "\tenable",
          "}"
      ].join("\n");
  }
docs: Create the js content of the file to add css