diff --git a/src/components/astro/ColCentre.astro b/src/components/astro/ColCentre.astro
index f67ea2f..fe7c548 100644
--- a/src/components/astro/ColCentre.astro
+++ b/src/components/astro/ColCentre.astro
@@ -5,7 +5,7 @@ import CarteOWrapper from '../vue/CarteOWrapper.vue';
 import ChatbotV2 from '../vue/ChatbotV2.vue';
 import EmbedDynamique from '../vue/EmbedDynamique.vue';
 ---
-<div id="col-centre-grid" class="h-full grid grid-rows-2 gap-2 p-2">
+<div id="col-centre-grid" class="h-full grid gap-2 p-2" style="grid-template-rows: 1fr 2fr;">
   <!-- HAUT 50% : tabs Carte O / Chatbot -->
   <section id="col-centre-haut" class="border border-neutral-200 rounded flex flex-col overflow-hidden bg-white" style="min-height: 0;">
     <nav role="tablist" aria-label="Vues centrales" class="flex border-b border-neutral-200 px-1 pt-1">
@@ -97,8 +97,8 @@ import EmbedDynamique from '../vue/EmbedDynamique.vue';
       haut.style.minHeight = '0';
       poignee?.setAttribute('aria-label', 'Deployer la Carte O');
     } else {
-      grid.classList.add('grid-rows-2');
-      grid.style.gridTemplateRows = '';
+      grid.classList.remove('grid-rows-2');
+      grid.style.gridTemplateRows = '1fr 2fr';
       haut.style.overflow = '';
       haut.style.minHeight = '';
       poignee?.setAttribute('aria-label', 'Replier la Carte O');
@@ -141,7 +141,7 @@ import EmbedDynamique from '../vue/EmbedDynamique.vue';
         const parts = rows.split(' ');
         return parseFloat(parts[0]) || 50;
       }
-      return 50;
+      return 33.33;
     };
 
     dragHandle.addEventListener('mousedown', (e: MouseEvent) => {
@@ -182,10 +182,10 @@ import EmbedDynamique from '../vue/EmbedDynamique.vue';
       gridEl.classList.remove('grid-rows-2');
     }
 
-    // Double-click sur drag handle = reset 50/50
+    // Double-click sur drag handle = reset default 1/3 + 2/3
     dragHandle.addEventListener('dblclick', () => {
-      gridEl.style.gridTemplateRows = '';
-      gridEl.classList.add('grid-rows-2');
+      gridEl.style.gridTemplateRows = '1fr 2fr';
+      gridEl.classList.remove('grid-rows-2');
       sessionStorage.removeItem('tf-centre-rows');
     });
   }