Fixes OpenClassrooms-Student-Center#1: modal btn now closes the modal

modal.js

@@ -11,6 +11,7 @@ function editNav() {
 const modalbg = document.querySelector(".bground");
 const modalBtn = document.querySelectorAll(".modal-btn");
 const formData = document.querySelectorAll(".formData");
+const closeBtn = document.getElementById("closeBtn");
 
 // launch modal event
 modalBtn.forEach((btn) => btn.addEventListener("click", launchModal));
@@ -20,4 +21,5 @@ function launchModal() {
   modalbg.style.display = "block";
 }
 
-
+// close modal form
+closeBtn.addEventListener("click", () => (modalbg.style.display = "none"));