diff --git a/customize.html b/customize.html
index b1f662cfee..ca044c0355 100644
--- a/customize.html
+++ b/customize.html
@@ -651,9 +651,9 @@ base_url: "../"
     <p>Define alert colors, border radius, and padding.</p>
     <h4>Border radius</h4>
     <label>@alert-padding</label>
-    <input type="text" class="form-control" placeholder="15px">
+    <input type="text" class="form-control" placeholder="15px" data-var="@alert-padding">
     <label>@alert-border-radius</label>
-    <input type="text" class="form-control" placeholder="@border-radius-base">
+    <input type="text" class="form-control" placeholder="@border-radius-base" data-var="@alert-border-radius">
     <div class="row">
       <div class="col-lg-6">
         <h4>Default (Warning)</h4>
@@ -999,7 +999,7 @@ base_url: "../"
 
     <h3>Wells</h3>
     <label>@well-bg</label>
-    <input type="text" class="form-control" placeholder="#f5f5f5">
+    <input type="text" class="form-control" placeholder="#f5f5f5" data-var="@well-bg">
 
     <h2 id="variables-accordion">Accordion</h2>
     <label>@accordion-border-bg</label>