Replace arrow functions with standard functions

script.js

@@ -7,10 +7,18 @@ const diff_enum = {
 };
 
 // Utility Functions
-const mv_x = (what, x) => what.style.left = x,
-    mv_y = (what, y) => what.style.top = y,
-    rand = (limit) => Math.random() * limit,
-    inRange = (lower, upper, what) => what >= lower && what <= upper;
+const mv_x = function mv_x(what, x) {
+    return what.style.left = x;
+},
+    mv_y = function mv_y(what, y) {
+    return what.style.top = y;
+},
+    rand = function rand(limit) {
+    return Math.random() * limit;
+},
+    inRange = function inRange(lower, upper, what) {
+    return what >= lower && what <= upper;
+};
 
 // Selectors. Duh!
 const catch_me = document.getElementById("catch_me"),
@@ -22,12 +30,22 @@ const catch_height = 50,
     catch_width = 100,
     difficulty = diff_enum.HARD; // CHANGE THIS FOR MORE FUN
 
-const incr_counter = () => counter.innerText = +counter.innerText + 1;
+const incr_counter = function incr_counter() {
+    return counter.innerText = +counter.innerText + 1;
+};
 // Next positions should be within the visible portion of the window.
-const rand_x = () => rand(window.innerWidth - catch_width),
-    rand_y = () => rand(window.innerHeight - catch_height),
-    mv_catch_x = () => mv_x(catch_me, rand_x()),
-    mv_catch_y = () => mv_y(catch_me, rand_y());
+const rand_x = function rand_x() {
+    return rand(window.innerWidth - catch_width);
+},
+    rand_y = function rand_y() {
+    return rand(window.innerHeight - catch_height);
+},
+    mv_catch_x = function mv_catch_x() {
+    return mv_x(catch_me, rand_x());
+},
+    mv_catch_y = function mv_catch_y() {
+    return mv_y(catch_me, rand_y());
+};
 
 // Initial State
 catch_me.style.position = "absolute";
@@ -39,14 +57,14 @@ mv_catch_y();
 
 // If you can get your mouse inside here you get a point.
 // But the question is, can you? ;)
-catch_me.addEventListener("mouseenter", () => {
+catch_me.addEventListener("mouseenter", function () {
     mv_catch_x();
     mv_catch_y();
     incr_counter();
 });
 
 // Track mouse movent inside body.
-body.addEventListener("mousemove", e => {
+body.addEventListener("mousemove", function (e) {
     const delta_x = e.offsetX - catch_me.offsetLeft,
         delta_y = e.offsetY - catch_me.offsetTop,
         xInRange = inRange(-difficulty, difficulty + catch_width, delta_x),