diff --git a/example/adder-test.html b/example/adder-test.html
index 040f155..8608810 100644
--- a/example/adder-test.html
+++ b/example/adder-test.html
@@ -1,16 +1,14 @@
 <script src="../tinytest.js"></script>
 <script src="adder.js"></script>
 <script>
-tests({
+  tests({
+    'adds numbers': function () {
+      eq(6, add(2, 4));
+      eq(6.6, add(2.6, 4));
+    },
 
-  'adds numbers': function() {
-    eq(6, add(2, 4));
-    eq(6.6, add(2.6, 4));
-  },
-
-  'subtracts numbers': function() {
-    eq(-2, add(2, -4));
-  },
-
-});
+    'subtracts numbers': function () {
+      eq(-2, add(2, -4));
+    },
+  });
 </script>
diff --git a/tinytest.js b/tinytest.js
index 183d0eb..4140fda 100644
--- a/tinytest.js
+++ b/tinytest.js
@@ -38,54 +38,55 @@
  * MIT License. See https://github.com/joewalnes/jstinytest/
  */
 const TinyTest = {
+  run(tests) {
+    let failures = 0;
 
-    run: function(tests) {
-        let failures = 0;
-        for (let testName in tests) {
-            let testAction = tests[testName];
-            try {
-                testAction();
-                console.log('Test:', testName, 'OK');
-            } catch (e) {
-                failures++;
-                console.error('Test:', testName, 'FAILED', e);
-                console.error(e.stack);
-            }
-        }
-        setTimeout(function() { // Give document a chance to complete
-            if (window.document && document.body) {
-                document.body.style.backgroundColor = (failures == 0 ? '#99ff99' : '#ff9999');
-            }
-        }, 0);
-    },
+    for (const testName in tests) {
+      const testAction = tests[testName];
 
-    fail: function(msg) {
-        throw new Error('fail(): ' + msg);
-    },
+      try {
+        testAction();
+        console.log(`Tests: ${testName} OK`);
+      } catch (e) {
+        failures++;
 
-    assert: function(value, msg) {
-        if (!value) {
-            throw new Error('assert(): ' + msg);
-        }
-    },
+        console.error(`Test: ${testName} FAILED`, e);
+        console.error(e.stack);
+      }
+    }
 
-    assertEquals: function(expected, actual) {
-        if (expected != actual) {
-            throw new Error('assertEquals() "' + expected + '" != "' + actual + '"');
-        }
-    },
+    document.addEventListener('DOMContentLoaded', function () {
+      document.body.style.backgroundColor =
+        failures == 0 ? '#99ff99' : '#ff9999';
+    });
+  },
 
-    assertStrictEquals: function(expected, actual) {
-        if (expected !== actual) {
-            throw new Error('assertStrictEquals() "' + expected + '" !== "' + actual + '"');
-        }
-    },
+  fail(msg) {
+    throw new Error(`fail(): ${msg}`);
+  },
 
+  assert(value, msg) {
+    if (!value) {
+      throw new Error(`assert: ${msg}`);
+    }
+  },
+
+  assertEquals(expected, actual) {
+    if (expected != actual) {
+      throw new Error(`assertEquals() ${expected} != ${actual}`);
+    }
+  },
+
+  assertStrictEquals(expected, actual) {
+    if (expected !== actual) {
+      throw new Error(`assertsStrictEquals() ${expected} !== ${actual}`);
+    }
+  },
 };
 
-const fail                = TinyTest.fail,
-      assert              = TinyTest.assert,
-      assertEquals        = TinyTest.assertEquals,
-      eq                  = TinyTest.assertEquals, // alias for assertEquals
-      assertStrictEquals  = TinyTest.assertStrictEquals,
-      tests               = TinyTest.run;
+const fail = TinyTest.fail,
+  assert = TinyTest.assert,
+  assertEquals = TinyTest.assertEquals,
+  eq = TinyTest.assertEquals, // alias for assertEquals
+  assertStrictEquals = TinyTest.assertStrictEquals,
+  tests = TinyTest.run;