diff --git a/src/components/FlowMap.tsx b/src/components/FlowMap.tsx
index ac7f120..8706582 100644
--- a/src/components/FlowMap.tsx
+++ b/src/components/FlowMap.tsx
@@ -350,7 +350,7 @@ export function FlowMap({ arcs, focusCity, onCityClick }: FlowMapProps) {
       {/* Bouton cluster / villes */}
       <button
         onClick={() => setClustered(c => !c)}
-        className={`absolute bottom-20 left-4 z-[600] px-3 py-1.5 rounded-lg text-xs font-medium border transition-all duration-200 ${
+        className={`absolute bottom-20 left-4 z-[1002] px-3 py-1.5 rounded-lg text-xs font-medium border transition-all duration-200 ${
           clustered
             ? 'bg-[#d4a843] text-[#0a0b0f] border-[#d4a843] shadow-[0_0_10px_rgba(212,168,67,0.35)]'
             : 'bg-[#0a0b0f]/90 text-[#6b7280] border-[#2e2f3a] hover:text-[#d4a843] hover:border-[#d4a843]'