@@ -3,6 +3,7 @@
 <head>
   <meta charset="UTF-8">
   <title>Scoped CSS Variables and JS</title>
+  <link rel='stylesheet' href='styles/main.css'>
 </head>
 <body>
   <h2>Update CSS Variables with <span class='hl'>JS</span></h2>
@@ -20,35 +21,8 @@ <h2>Update CSS Variables with <span class='hl'>JS</span></h2>
 
   <img src="https://source.unsplash.com/7bwQXzbF6KE/800x500">
 
-  <style>
 
-    /*
-      misc styles, nothing to do with CSS variables
-    */
-
-    body {
-      text-align: center;
-    }
-
-    body {
-      background: #193549;
-      color: white;
-      font-family: 'helvetica neue', sans-serif;
-      font-weight: 100;
-      font-size: 50px;
-    }
-
-    .controls {
-      margin-bottom: 50px;
-    }
-
-    input {
-      width:100px;
-    }
-  </style>
-
-  <script>
-  </script>
+  <script src='js/app.js'></script>
 
 </body>
 </html>
@@ -0,0 +1,9 @@
+const inputs = document.querySelectorAll('.controls input');
+
+function handleUpdate() {
+  const suffix = this.dataset.sizing || '';
+  document.documentElement.style.setProperty(`--${this.name}`, this.value + suffix);
+}
+
+inputs.forEach(input => input.addEventListener('change', handleUpdate));
+inputs.forEach(input => input.addEventListener('mousemove', handleUpdate));
@@ -0,0 +1,36 @@
+
+:root {
+  --base: #ffc600;
+  --spacing: 10px;
+  --blur: 10px;
+}
+
+img {
+  padding: var(--spacing);
+  background: var(--base);
+  filter: blur(var(--blur));
+}
+
+.hl {
+  color: var(--base);
+}
+
+body {
+  text-align: center;
+}
+
+body {
+  background: #193549;
+  color: white;
+  font-family: 'helvetica neue', sans-serif;
+  font-weight: 100;
+  font-size: 50px;
+}
+
+.controls {
+  margin-bottom: 50px;
+}
+
+input {
+  width:100px;
+}