title: change background color of div on button click
body: <p>In my code behind i am generating html string</p>
  
  <pre><code>&lt;a href='#' class='my-post' onclick='myFunc(" + Id + ")'&gt;
       &lt;div class='my-idea'&gt;
          &lt;span &gt;23&lt;/span&gt;
          &lt;span class='heart'&gt;&lt;/span&gt;
       &lt;/div&gt;
  &lt;/a&gt;
  </code></pre>
  
  <p>I have implemented <code>myFunc</code> function in code behind as below</p>
  
  <pre><code>funcString += "function myFunc(id){";
  funcString += "document.getElementById(\"" + btn1.ClientID + "\").click();"; 
  funcString += "}";
  </code></pre>
  
  <p>Then on <code>btn1</code> click event i do some processing</p>
  
  <pre><code>protected void btnSubmitWinnerPage_Click(object sender, EventArgs e)
      {
        // some processing
      }
  </code></pre>
  
  <p>Now i want to change background color of div inside that href tag when button is clicked. How can i achieve?</p>