.app-surface-card{margin:60px auto;padding:32px 24px;background:#f9f9fb;border-radius:12px;box-shadow:0 2px 12px #00000014;font-family:Segoe UI,Arial,sans-serif;color:#222}.app-btn{padding:10px 24px;border:none;border-radius:6px;font-size:1rem;cursor:pointer;transition:opacity .2s}.app-btn:hover:not(:disabled){opacity:.9}.app-btn:disabled{opacity:.6;cursor:not-allowed}.app-btn-primary{background:#2563eb;color:#fff}.app-btn-secondary{background:#e5e7eb;color:#222}