diff --git a/apps/pwa/src/styles/index.css b/apps/pwa/src/styles/index.css
index 4f1da5b..28e1eed 100644
--- a/apps/pwa/src/styles/index.css
+++ b/apps/pwa/src/styles/index.css
@@ -103,6 +103,12 @@ body {
  */
 .sx__date-grid,
 .sx__month-grid-day__events {
+  /* Fallback: Schedule-X uses the built-in `primary` family for any event whose
+   * calendar colorName is not registered (e.g. a member calendar absent from the
+   * current /api/me members list). Remapping it keeps all-day events solid-filled
+   * even in that fallback case, so the pill never degrades to the light tint. */
+  --sx-color-primary-container: var(--sx-color-primary);
+  --sx-color-on-primary-container: #FFFFFF;
   --sx-color-shared-container: var(--sx-color-shared);
   --sx-color-on-shared-container: #FFFFFF;
   --sx-color-member-1-container: var(--sx-color-member-1);