doemuu.js

function includeHTML() {
  var z, i, elmnt, file, xhttp;
  /*loop through a collection of all HTML elements:*/
  z = document.getElementsByTagName("*");
  for (i = 0; i < z.length; i++) {
    elmnt = z[i];
    /*search for elements with a certain atrribute:*/
    file = elmnt.getAttribute("include-html");
    if (file) {
      /*make an HTTP request using the attribute value as the file name:*/
      xhttp = new XMLHttpRequest();
      xhttp.onreadystatechange = function() {
        if (this.readyState == 4) {
          if (this.status == 200) {
            elmnt.innerHTML = this.responseText;
          }
          if (this.status == 404) {
            elmnt.innerHTML = "Page not found.";
          }
          /*remove the attribute, and call this function once more:*/
          elmnt.removeAttribute("include-html");
          includeHTML();
        }
      }
      xhttp.open("GET", file, true);
      xhttp.send();
      /*exit the function:*/
      return;
    }
  }
};

/* Toggle between adding and removing the "responsive" class to topnav when the user clicks on the icon */
function myFunction() {
  var x = document.getElementById("myTopnav");
  if (x.className === "topnav") {
    x.className += " responsive";
  } else {
    x.className = "topnav";
  }
}