so I did the tutorial correctly but when I go back to the index page the links are both highlighted / underlined

Hi Ryan,

This is because the $section variable is undefined on the index page but the nav scripts are still running on that page. php outputs a notice level error informing you about the use of an undefined variable. This error is output where the scripts are which is right inside your class attribute.

This means each part of that message is interpreted as a class name by the browser and it just so happens that some style rules end up matching and you get the unintended styling that you see.

One solution is to just set the $section variable to something on the index page even though you're not going to use it. You have to remember to do this on every page though.

The solution I used was to update the scripts to first check if the variable is set first before using it.

<li class="shirts<?php if ( isset($section) && $section == "shirts") { echo " on"; } ?>"><a href="shirts.php">Shirts</a></li>
<li class="contact<?php if ( isset($section) && $section == "contact") { echo " on"; } ?>"><a href="contact.php">Contact</a></li>