feat: improve design trough the whole application

frontend/src/routes/settings/admin/oidc-clients/oidc-client-preview-modal.svelte

@@ -115,7 +115,7 @@
 				</div>
 			{/if}
 
-			<div class="flex justify-start gap-3">
+			<div class="flex flex-col sm:flex-row justify-start gap-3">
 				<Field.Field class="w-auto min-w-48">
 					<Field.Label>{m.users()}</Field.Label>
 					<SearchableSelect

frontend/src/routes/settings/admin/users/[id]/+page.svelte

@@ -132,7 +132,7 @@
 	</div>
 </CollapsibleCard>
 
-<Item.Group class="bg-card rounded-xl border p-4 shadow-sm">
+<Item.Group class="bg-card border p-4 shadow-sm">
 	<Item.Root class="border-none bg-transparent p-0">
 		<Item.Media class="text-primary/80">
 			<KeyRound class="size-5" />