diff --git a/css/admin.css b/css/admin.css
index acc208e..a5cc829 100644
--- a/css/admin.css
+++ b/css/admin.css
@@ -177,6 +177,9 @@ input[type="checkbox"]:checked::after { content: '✓'; color: var(--background)
 
 /* Correction affichage zone import */
 #import-box, .import-box {
+    display: block; /* <-- Ligne clé pour réparer la bordure */
+    width: 100%;
+    box-sizing: border-box;
     border: 2px dashed var(--border);
     border-radius: 8px;
     padding: 2rem 1rem;