diff --git a/backend/static/style.css b/backend/static/style.css
index 35d7334..2eb63f3 100644
--- a/backend/static/style.css
+++ b/backend/static/style.css
@@ -108,6 +108,10 @@ td:last-child, td button { white-space: nowrap; }
 td button + button { margin-left: 0.4rem; }
 
 /* modal */
+/* NOTE: keep `hidden` winning over the flex display below, otherwise the
+   backdrop is permanently visible and blocks everything underneath. */
+#editor-backdrop[hidden] { display: none; }
+
 #editor-backdrop {
   position: fixed;
   inset: 0;