feat: Passwordless cross-device authentication

- Arkitektur: docs/auth/passwordless-architecture.md
- Backend: iom/quixzoom-auth-service/ (FastAPI + Redis)
- Webb: quixzoom-market-pages/se/login/ (QR-kod + polling)
- App: iom/quixzoom-app/src/features/auth/ (push + deep links)

Flöde: QR-kod → app-godkännande → webb-inloggad

landvex-site/use-cases/infrastructure-risk/index.html

@@ -138,7 +138,7 @@
     .evidence-card p { font-size: 14px; color: var(--text-dim); line-height: 1.6; }
 
     .cta-banner {
-      background: #e8f0fe; border-radius: 16px; padding: 40px 48px;
+      background: #e8f0fe; border-radius: var(--radius-lg); padding: 40px 48px;
       display: flex; align-items: center; gap: 48px; flex-wrap: wrap; margin-top: 48px;
     }
     .cta-banner h3 { color: #1d1d1f; font-size: 1.25rem; font-weight: 800; margin-bottom: 8px; }
@@ -184,13 +184,13 @@
     .footer-links a { font-size: 14px; color: var(--text-muted); transition: color 0.2s; }
     .footer-links a:hover { color: #1d1d1f; }
     .footer-social {
-      width: 32px; height: 32px; border: 1px solid var(--border); border-radius: 8px;
+      width: 32px; height: 32px; border: 1px solid var(--border); border-radius: var(--radius-md);
       display: flex; align-items: center; justify-content: center;
       transition: border-color 0.2s, background 0.2s;
     }
     .footer-social:hover { border-color: rgba(0,0,0,0.25); background: rgba(0,0,0,0.04); }
 
-    .lv-disclaimer{font-size:.75rem;color:rgba(0,0,0,.75);margin-top:24px;padding:12px 16px;background:rgba(0,0,0,.04);border-radius:8px;line-height:1.6;max-width:800px}
+    .lv-disclaimer{font-size:.75rem;color:rgba(0,0,0,.75);margin-top:24px;padding:12px 16px;background:rgba(0,0,0,.04);border-radius: var(--radius-md);line-height:1.6;max-width:800px}
     .lv-disclaimer a{color:rgba(0,0,0,.65);text-decoration:underline}
 
     @media (max-width: 900px) {