diff --git a/comparisons/forms/color_picker/html.html b/comparisons/forms/color_picker/html.html
index a2e754d..c9d6c13 100644
--- a/comparisons/forms/color_picker/html.html
+++ b/comparisons/forms/color_picker/html.html
@@ -1,3 +1,4 @@
 <form>
   <input type="color" aria-label="Select a color" />
+  <button type="submit">Submit</button>
 </form>
diff --git a/comparisons/navigation/accordion/html.html b/comparisons/navigation/accordion/html.html
index aba9737..9d40105 100644
--- a/comparisons/navigation/accordion/html.html
+++ b/comparisons/navigation/accordion/html.html
@@ -1,19 +1,19 @@
-<div class="togglebox">
-  <input id="toggle1" type="radio" name="toggle" />
-  <label for="toggle1">Label 1</label>
+<div class="togglebox" role="tablist">
+  <input id="toggle1" type="radio" name="toggle" aria-hidden="true" />
+  <label for="toggle1" role="tab" tabindex="0" aria-describedby="content-area1">Label 1</label>
   <section id="content1">
-    <p>Content for the first accordion</p>
+    <p id="content-area1">Content for the first accordion</p>
   </section>
   
-  <input id="toggle2" type="radio" name="toggle" />
-  <label for="toggle2">Label 2</label>
+  <input id="toggle2" type="radio" name="toggle" aria-hidden="true" />
+  <label for="toggle2" role="tab" tabindex="0" aria-describedby="content-area2">Label 2</label>
   <section id="content2">
-    <p>Content for the second accordion</p>
+    <p id="content-area2">Content for the second accordion</p>
   </section>
   
-  <input id="toggle3" type="radio" name="toggle" />
-  <label for="toggle3">Label 3</label>
+  <input id="toggle3" type="radio" name="toggle" aria-hidden="true" />
+  <label for="toggle3" role="tab" tabindex="0" aria-describedby="content-area3">Label 3</label>
   <section id="content3">
-    <p>Content for the third accordion</p>
+    <p id="content-area3">Content for the third accordion</p>
   </section>
-</div>
\ No newline at end of file
+</div>
diff --git a/comparisons/navigation/lightbox/html.html b/comparisons/navigation/lightbox/html.html
index 6c4e8ca..a3b7373 100644
--- a/comparisons/navigation/lightbox/html.html
+++ b/comparisons/navigation/lightbox/html.html
@@ -1,9 +1,9 @@
 <!-- thumbnail image wrapped in a link -->
 <a href="#img1">
-  <img src="img.jpg" class="thumbnail">
+  <img src="img.jpg" class="thumbnail" alt="image description">
 </a>
 
 <!-- lightbox container hidden with CSS -->
 <a href="#" class="lightbox" id="img1">
-  <img src="img.jpg">
-</a>
\ No newline at end of file
+  <img src="img.jpg" alt="image description">
+</a>
diff --git a/comparisons/navigation/tabs/html.html b/comparisons/navigation/tabs/html.html
index 063b487..9cf1a8b 100644
--- a/comparisons/navigation/tabs/html.html
+++ b/comparisons/navigation/tabs/html.html
@@ -1,25 +1,25 @@
-<div class="tabs">    
-   <div class="tab">
+<div class="tabs" role="tablist">    
+   <div class="tab" role="tab">
        <input type="radio" name="tabgroup" id="tab-1" checked>
-       <label for="tab-1">Label One</label>
+       <label for="tab-1" tabindex="0" aria-describedby="content-area1">Label One</label>
        <div class="content">
-          <p>Tab One Content</p>
+          <p id="content-area1">Tab One Content</p>
        </div> 
    </div>
     
-   <div class="tab">
+   <div class="tab" role="tab">
        <input type="radio" name="tabgroup" id="tab-2">
-       <label for="tab-2">Label Two</label>
+       <label for="tab-2" tabindex="0" aria-describedby="content-area2">Label Two</label>
        <div class="content">
-           <p>Tab Two Content</p>
+           <p id="content-area2">Tab Two Content</p>
        </div> 
    </div>
     
-    <div class="tab">
+    <div class="tab" role="tab">
        <input type="radio" name="tabgroup" id="tab-3">
-       <label for="tab-3">Label Three</label>
+       <label for="tab-3" tabindex="0" aria-describedby="content-area3">Label Three</label>
        <div class="content">
-           <p>Tab Three Content</p>
+           <p id="content-area3">Tab Three Content</p>
        </div> 
    </div>
-</div>
\ No newline at end of file
+</div>