feat: distribute animated DrillBitSpinner across all major components as a background watermark

Former-commit-id: ad28a5d93b773be795cd0d73fd6ed2accd257a10

components/layout/Footer.tsx

@@ -4,6 +4,7 @@ import { useLocale } from 'next-intl';
 import { ShieldCheck, Leaf, Lock, Accessibility, Zap } from 'lucide-react';
 import { LanguageSwitcher } from './LanguageSwitcher';
 import { StratumLines } from '@/components/ui/decorations/StratumLines';
+import { DrillBitSpinner } from '@/components/ui/decorations/DrillBitSpinner';
 
 interface CompanyInfo {
   contactEmail: string;
@@ -151,6 +152,10 @@ export function Footer({ companyInfo }: FooterProps) {
           <div className="flex items-center gap-2"><Zap className="w-4 h-4 text-white/40" /><span>High Performance</span></div>
         </div>
       </div>
+      {/* Decorative: large abstract drill bit spinning slowly in background */}
+      <div className="absolute top-1/2 -translate-y-1/2 -right-48 pointer-events-none opacity-[0.03]">
+        <DrillBitSpinner size={600} duration={30} glow={false} />
+      </div>
       {/* Decorative: abstract earth strata */}
       <StratumLines placement="bottom-right" />
     </footer>