diff --git a/resources/sass/_header.scss b/resources/sass/_header.scss
index e06dcde6f..12f098a1b 100644
--- a/resources/sass/_header.scss
+++ b/resources/sass/_header.scss
@@ -221,17 +221,21 @@ header .search-box {
   z-index: 5;
   background-color: #FFF;
   border-bottom: 1px solid #DDD;
+  @include lightDark(border-bottom-color, #DDD, #333);
   box-shadow: $bs-card;
 }
 .tri-layout-mobile-tab {
   text-align: center;
   border-bottom: 3px solid #BBB;
   cursor: pointer;
+  @include lightDark(background-color, #FFF, #222);
+  @include lightDark(border-bottom-color, #BBB, #333);
   &:first-child {
     border-inline-end: 1px solid #DDD;
+    @include lightDark(border-inline-end-color, #DDD, #000);
   }
   &[aria-selected="true"] {
-    border-bottom-color: currentColor;
+    border-bottom-color: currentColor !important;
   }
 }