diff --git a/theme/boost/scss/moodle/blocks.scss b/theme/boost/scss/moodle/blocks.scss
index bf26c7a3adf..3f95ab48283 100644
--- a/theme/boost/scss/moodle/blocks.scss
+++ b/theme/boost/scss/moodle/blocks.scss
@@ -347,13 +347,6 @@ $card-gutter : $card-deck-margin * 2;
     color: $text-muted;
 }
 
-@include media-breakpoint-down(sm) {
-    .block.card {
-        border-left: 0;
-        border-right: 0;
-    }
-}
-
 .block_social_activities li a.movehere,
 .block_site_main_menu li a.movehere {
     display: block;
diff --git a/theme/boost/style/moodle.css b/theme/boost/style/moodle.css
index b8d19d8a014..d222c26414e 100644
--- a/theme/boost/style/moodle.css
+++ b/theme/boost/style/moodle.css
@@ -16895,12 +16895,6 @@ aside[id^=block-region-side-] .block_recentlyaccesseditems .dashboard-card-deck
   color: #6a737b;
 }
 
-@media (max-width: 767.98px) {
-  .block.card {
-    border-left: 0;
-    border-right: 0;
-  }
-}
 .block_social_activities li a.movehere,
 .block_site_main_menu li a.movehere {
   display: block;
diff --git a/theme/classic/style/moodle.css b/theme/classic/style/moodle.css
index 18a7eb4d27f..568285a7e55 100644
--- a/theme/classic/style/moodle.css
+++ b/theme/classic/style/moodle.css
@@ -16895,12 +16895,6 @@ aside[id^=block-region-side-] .block_recentlyaccesseditems .dashboard-card-deck
   color: #6a737b;
 }
 
-@media (max-width: 767.98px) {
-  .block.card {
-    border-left: 0;
-    border-right: 0;
-  }
-}
 .block_social_activities li a.movehere,
 .block_site_main_menu li a.movehere {
   display: block;