The darkmode toggle button needed the parent s-btn class

Author: aaronshekey

docs/_includes/header.html

@@ -32,7 +32,7 @@
             <svg aria-hidden="true" class="svg-icon iconCodepen" width="24" height="24" viewBox="0 0 18 18"><path d="M12.67 8.17l-2.98-2v-3.2l5.38 3.6-2.4 1.6zM13.9 9l1.73-1.15v2.3L13.9 9zm-4.2 2.82l2.98-2 2.4 1.62-5.38 3.59v-3.2zm-4.36-2l2.98 2v3.2l-5.38-3.58 2.4-1.61zM4.1 9l-1.73 1.15v-2.3L4.1 9zm4.2-2.82l-2.98 2-2.4-1.62L8.3 2.97v3.2zm.7 4.45L6.57 9 9 7.37 11.43 9 9 10.63zm7.99-4.19l-.01-.05-.01-.04-.02-.05-.02-.03a.6.6 0 0 0-.02-.05l-.02-.03a.69.69 0 0 0-.15-.17L16.7 6h-.02L9.4 1.11a.69.69 0 0 0-.77 0L1.3 5.99h-.02c0 .02-.02.02-.03.03a.81.81 0 0 0-.12.13.69.69 0 0 0-.03.04l-.02.03-.02.05-.02.03-.02.05v.04L1 6.44v.03a.7.7 0 0 0-.01.1v4.87a.7.7 0 0 0 0 .09l.01.03.01.05.01.04.02.05.02.03a.51.51 0 0 0 .07.12.53.53 0 0 0 .08.1c.02 0 .03.02.04.03l.03.02h.02l7.3 4.88a.69.69 0 0 0 .77 0l7.31-4.87h.02c0-.02.02-.02.03-.03a.72.72 0 0 0 .04-.04l.02-.02a.62.62 0 0 0 .13-.19l.02-.03a.6.6 0 0 0 .02-.05v-.04l.02-.05v-.03a.7.7 0 0 0 .01-.1V6.57a.7.7 0 0 0 0-.09l-.01-.03z"/></svg>
         </a>
 
-        <button class="s-btn__unset c-pointer grid--cell fc-black-300 ml12 sm:d-none js-darkmode-btn" title="Toggle dark mode">
+        <button class="s-btn s-btn__unset c-pointer grid--cell fc-black-300 ml12 sm:d-none js-darkmode-btn" title="Toggle dark mode">
             {% icon "Theme", "", "24" %}
         </button>