I could but I gave you the tool so you can find it for yourself (now and in the future). WHY don’t you follow the instructions in that article? What stops you from learning the basics?
The artcile says to look at your Source code. If you did, you can easily find the portion where all those links (Home, About etc.) are:
<div id="topy">
<div id="menuv">
<ul>
<li class="current_page_item"><a href="https://reasonpad.com/" title="Home">Home</a></li>
<li class="page_item page-item-2"><a href="https://reasonpad.com/?page_id=2" title="About">About</a></li>
<li class="page_item page-item-11"><a href="https://reasonpad.com/?page_id=11" title="Contact us">Contact us</a></li>
<li class="page_item page-item-18"><a href="https://reasonpad.com/?page_id=18" title="Privacy">Privacy</a></li>
<li class="admintab"><a href="https://reasonpad.com/wp-login.php?action=register">Register</a></li> </ul>
</div>
</div>
And it tells you EXACTLY that they are placed in a div that has an ID “topy”.
Next, all you have to do find that div’s definition in your stylesheet:
#topy {…}
and edit the background colour of it.
So, next time try to NOT talk back to me without reading the resources and trying to follow the instructions.