Issue #3211888 by mherchel, Gauravmahlawat: Olivero: Layout Builder 33/34/33 layout broken in IE11

core/themes/olivero/css/layout/layout-builder-threecol-section.css

@@ -76,6 +76,6 @@
     .layout--threecol-section--33-34-33 > .layout__region--first,
     .layout--threecol-section--33-34-33 > .layout__region--second,
     .layout--threecol-section--33-34-33 > .layout__region--third {
-      flex-basis: calc(33.33% - 1.4985rem);
+      flex-basis: calc(33.33% - 1.50075rem);
     }
 }

core/themes/olivero/css/layout/layout-builder-threecol-section.pcss.css

@@ -73,7 +73,7 @@
     & > .layout__region--first,
     & > .layout__region--second,
     & > .layout__region--third {
-      flex-basis: calc(33.33% - (var(--grid-gap--md) * 0.666));
+      flex-basis: calc(33.33% - (var(--grid-gap--md) * 0.667));
     }
   }
 }