title: How to limit the number of selected checkboxes?
body: <p>I have the following HTML:</p>
  <pre class="lang-html prettyprint-override"><code>&lt;div class=&quot;pricing-levels-3&quot;&gt;
     &lt;p&gt;&lt;strong&gt;Which level would you like? (Select 3 Levels)&lt;/strong&gt;&lt;/p&gt;
     &lt;input class=&quot;single-checkbox&quot;type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 1&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 2&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 3&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 4&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 5&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 6&lt;br&gt;
     &lt;input class=&quot;single-checkbox&quot; type=&quot;checkbox&quot; name=&quot;vehicle&quot; value=&quot;Bike&quot;&gt;Level 7&lt;br&gt;
  &lt;/div&gt;
  </code></pre>
  <p>Live site:</p>
  <p><a href="http://www.chineselearnonline.com/amember/signup20.php" rel="nofollow noreferrer">http://www.chineselearnonline.com/amember/signup20.php</a></p>
  <p>How can I do it so that the user can only select 3 of those checkboxes?</p>