title: show html div if count of numbers equal 16 (cc verfication)
body: <p>I am beginner with javascript.</p>
  
  <p>I am trying to make something with javascript.</p>
  
  <p>But I have ended up with a lot of inoperative codes</p>
  
  <p>This is my html code</p>
  
  <pre><code>&lt;input name="cc_number"&gt;
  
  &lt;div id="hidee" style="display:none"&gt;
  &lt;input name="cvv2"&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I am trying to make it shown by javascript, if the number of chars in the "cc_number input" is 16</p>
  
  <p>My idea is counting characters and make a condition if they equals 16 then show the div.</p>
  
  <p>but I failed to build the code.</p>
  
  <p>Thanks</p>