fix: enforce semantic contrast across admin

src/app/admin/articles/page.tsx

@@ -35,7 +35,7 @@ export default async function AdminArticles({ searchParams }: { searchParams: Pr
         </Link>
       </div>
 
-      {error ? <p className="text-xs text-red-600 dark:text-red-400 mb-4">Error: {error}</p> : null}
+      {error ? <p className="text-xs text-[var(--color-error-text-readable)] dark:text-[var(--color-error-text-readable)] mb-4">Error: {error}</p> : null}
 
       <div className="grid grid-cols-[repeat(auto-fit,minmax(180px,1fr))] gap-3.5 mb-6">
         <StatusCard label={t("articlesShown")} value={articles.length} icon="📰" />
@@ -62,10 +62,10 @@ export default async function AdminArticles({ searchParams }: { searchParams: Pr
                   <td>
                     <Link href={`/admin/articles/${a.id}`}>{a.title}</Link>
                   </td>
-                  <td className="text-sm text-gray-500 dark:text-gray-400 whitespace-nowrap">
+                  <td className="text-sm theme-text-muted dark:theme-text-muted whitespace-nowrap">
                     <code>{a.slug}</code>
                   </td>
-                  <td className="text-sm text-gray-500 dark:text-gray-400 whitespace-nowrap">
+                  <td className="text-sm theme-text-muted dark:theme-text-muted whitespace-nowrap">
                     {a.createdAt ? a.createdAt.toISOString().slice(0, 10) : "—"}
                   </td>
                   <td>