1 files changed, 26 insertions, 0 deletions
diff --git a/demo/src/js/lib/tab-focus.js b/demo/src/js/lib/tab-focus.js
new file mode 100644
index 00000000..06e51203
--- /dev/null
+++ b/demo/src/js/lib/tab-focus.js
@@ -0,0 +1,26 @@
+// ==========================================================================
+// tab-focus.js
+// Detect keyboard tabbing
+// ==========================================================================
+
+(function() {
+    var className = 'tab-focus';
+
+    // Remove class on blur
+    document.addEventListener('focusout', function(event) {
+        event.target.classList.remove(className);
+    });
+
+    // Add classname to tabbed elements
+    document.addEventListener('keydown', function(event) {
+        if (event.keyCode !== 9) {
+            return;
+        }
+
+        // Delay the adding of classname until the focus has changed
+        // This event fires before the focusin event
+        window.setTimeout(function() {
+            document.activeElement.classList.add(className);
+        }, 0);
+    });
+})();