diff --git a/app/missions/[missionId]/page.tsx b/app/missions/[missionId]/page.tsx
index f97272db..7baa6f58 100644
--- a/app/missions/[missionId]/page.tsx
+++ b/app/missions/[missionId]/page.tsx
@@ -592,16 +592,52 @@ export default function MissionDetailPage() {
               <div className="space-y-4">
                 <Textarea
                   value={editedPlan}
-                  onChange={(e) => setEditedPlan(e.target.value)}
+                  onChange={(e) => {
+                    setEditedPlan(e.target.value);
+                    // Auto-resize textarea
+                    e.target.style.height = 'auto';
+                    e.target.style.height = e.target.scrollHeight + 'px';
+                  }}
                   placeholder="Le plan d'action généré apparaîtra ici. Vous pouvez le modifier après génération."
-                  className="min-h-[400px] font-mono text-sm bg-white text-gray-900 border-gray-300 focus:border-blue-500 focus:ring-blue-500"
+                  className="min-h-[600px] font-mono text-sm bg-white text-gray-900 border-gray-300 focus:border-blue-500 focus:ring-blue-500 resize-none overflow-hidden"
+                  style={{ height: 'auto' }}
+                  ref={(textarea) => {
+                    // Auto-resize on mount
+                    if (textarea) {
+                      textarea.style.height = 'auto';
+                      textarea.style.height = Math.max(600, textarea.scrollHeight) + 'px';
+                    }
+                  }}
                 />
-                {isPlanModified && (
-                  <p className="text-sm text-amber-600 flex items-center gap-1">
-                    <span className="w-2 h-2 bg-amber-500 rounded-full"></span>
-                    Modifications non sauvegardées
-                  </p>
-                )}
+                
+                {/* Bottom action bar */}
+                <div className="flex items-center justify-between pt-4 border-t border-gray-200">
+                  {isPlanModified ? (
+                    <>
+                      <p className="text-sm text-amber-600 flex items-center gap-1">
+                        <span className="w-2 h-2 bg-amber-500 rounded-full"></span>
+                        Modifications non sauvegardées
+                      </p>
+                      <Button
+                        onClick={handleSavePlan}
+                        disabled={savingPlan}
+                        className="bg-green-600 hover:bg-green-700 text-white"
+                      >
+                        {savingPlan ? (
+                          <Loader2 className="h-4 w-4 mr-2 animate-spin" />
+                        ) : (
+                          <Save className="h-4 w-4 mr-2" />
+                        )}
+                        Sauvegarder les modifications
+                      </Button>
+                    </>
+                  ) : (
+                    <p className="text-sm text-green-600 flex items-center gap-1">
+                      <span className="w-2 h-2 bg-green-500 rounded-full"></span>
+                      Plan sauvegardé
+                    </p>
+                  )}
+                </div>
               </div>
             ) : (
               <div className="flex flex-col items-center justify-center py-16 text-center">