refactor: css cleanup and style tweaks

src/layouts/MainGridLayout.astro

@@ -90,7 +90,7 @@ const mainPanelTop = siteConfig.banner.enable ? `calc(${BANNER_HEIGHT}vh - ${MAI
 </div>
 
 <!-- The things that should be under the banner, only the TOC for now -->
-<div class="absolute w-full z-0">
+<div class="absolute w-full z-0 hidden 2xl:block">
     <div class="relative max-w-[var(--page-width)] mx-auto">
         <!-- TOC component -->
         {siteConfig.toc.enable && <div id="toc-wrapper" class:list={["hidden lg:block transition absolute top-0 -right-[var(--toc-width)] w-[var(--toc-width)] flex items-center",