Fix theme consistency, i18n completeness, CSS variable naming, and hardcoded strings

src/app/admin/photos/page.tsx

@@ -44,7 +44,7 @@ export default async function AdminPhotos() {
         {photos.length === 0 ? (
           <div className="admin-empty">{t("noPhotos")}</div>
         ) : (
-          <div className="grid cols-3">
+          <div className="grid grid-cols-1 gap-4 md:grid-cols-3">
             {photos.map((p) => (
               <div key={String(p.id)} className="admin-card" style={{ padding: 0, overflow: "hidden" }}>
                 {/* eslint-disable-next-line @next/next/no-img-element */}