make site dark mode if js is disabled and fix instances

src/lib/app.css

@@ -9,9 +9,6 @@ html {
 	--accent-translucent: #00a58498;
 	--font-primary: Raleway;
 	--font-header: Raleway;
-}
-
-html.dark {
 	--primary: #151515;
 	--secondary: #252525;
 	--tertiary: #353535;

src/routes/instances.svelte

@@ -19,7 +19,7 @@
             <div class="container">
                 {#each groups as group}
                     <div class="container-inner">
-                        <h1>{group.category}</h1>
+                        <h2>{group.category}</h2>
                         <div class="items">
                             {#each group.values as item }
                                 <CardInner title={item.name} description={item.description} icon={item.icon}>