Links that are being called through ssi are not working on my website?

I used to be able to do this all of the time, but I'm having a serious block right now. I guess.

I have a basic .html webpage. I'm using ssi to call upon the header, footer, and navigation pane. My .htaccess file is parsing the .html files as .shtml.

None of the links in my navigation pane are working for some reason.

I checked the code, and that is where the block is coming in. I'm staring at this, and something is wrong with  it, but I can't figure it out.

<li class="dropdown">

    <a href="website-demonstration.html">

    <a href="javascript:void(0)" class="dropbtn">Leeighton's Anime Walkthrough</a>

    </a>

    <div class="dropdown-content">

    <a href="website-walkthroughs.html">

    <a href="#">Walkthroughs</a>

    </a>

    <a href="biographies.html">

    <a href="#">Biographies</a>

    </a>

    <a href="what-not-to-do.html">

    <a href="#">What you shouldn't do</a>

    </a>

    <a href="pictures.html">

    <a href="#">Pictures</a>

    </a>
    
    <a href="additional-walkthroughs.html">

    <a href="#">Additional walkthroughs</a>

    </a>
    
    <a href="resources-and-information.html">

    <a href="#">Resources and information</a>

    </a>
    
    <a href="background-music.html">

    <a href="#">Background-music</a>

    </a>
    
    <a href="video-releases.html">

    <a href="#">video releases</a>

    </a>

They won't link to the pages, even though they exist. They're already on the server, too.

What is wrong with this?

Thank you.