Add web-vanilla

web-vanilla/shared.js

@@ -0,0 +1,13 @@
+
+function create_prologue() {
+    let back_to_index = document.createElement("a");
+    back_to_index.setAttribute("href", "../index.html");
+    back_to_index.innerHTML = "Back to index";
+
+    let title = document.createElement("h1");
+    title.innerText = document.title;
+
+    let body = document.getElementsByTagName("body")[0];
+    body.insertBefore(title, body.firstChild);
+    body.insertBefore(back_to_index, body.firstChild);
+}