function loadCSS(filename){ 
      var file = document.createElement("link");
      file.setAttribute("rel", "stylesheet");
      file.setAttribute("type", "text/css");
      file.setAttribute("href", filename);
      document.head.appendChild(file);
   }

   //just call a function to load your CSS
   //this path should be relative your HTML location
   loadCSS("https://api.akasa.lk/websites/musp.org.css");