diff --git a/theme/boost/scss/moodle/blocks.scss b/theme/boost/scss/moodle/blocks.scss
index 980888cbce0c8..1d5b33fdf5839 100644
--- a/theme/boost/scss/moodle/blocks.scss
+++ b/theme/boost/scss/moodle/blocks.scss
@@ -63,6 +63,9 @@ $blocks-plus-gutter: $blocks-column-width + ( $grid-gutter-width / 2 );
     width: calc(100% - #{$blocks-plus-gutter});
     @include media-breakpoint-down(lg) {
         width: 100%;
+        /* MDL-63102 - Remove extra space at bottom.
+        If modifying make sure block-region is horizontally stacked when in full screen */
+        display: block;
     }
 }
 
diff --git a/theme/boost/scss/moodle/core.scss b/theme/boost/scss/moodle/core.scss
index c3e9c48653c2d..7fc00a8717eff 100644
--- a/theme/boost/scss/moodle/core.scss
+++ b/theme/boost/scss/moodle/core.scss
@@ -2148,4 +2148,4 @@ div.editor_atto_toolbar button .icon {
     .dir-ltr-hide {
         display: none;
     }
-}
\ No newline at end of file
+}
diff --git a/theme/boost/style/moodle.css b/theme/boost/style/moodle.css
index 6e3e54f497606..2059e48c87da4 100644
--- a/theme/boost/style/moodle.css
+++ b/theme/boost/style/moodle.css
@@ -11125,7 +11125,10 @@ div.editor_atto_toolbar button .icon {
   @media (max-width: 1199.98px) {
     #region-main-settings-menu.has-blocks,
     #region-main.has-blocks {
-      width: 100%; } }
+      width: 100%;
+      /* MDL-63102 - Remove extra space at bottom.
+        If modifying make sure block-region is horizontally stacked when in full screen */
+      display: block; } }
 
 @media (max-width: 1199.98px) {
   [data-region="blocks-column"] {
diff --git a/theme/boost/templates/columns2.mustache b/theme/boost/templates/columns2.mustache
index 704705521933b..4ff79b6e57cfa 100644
--- a/theme/boost/templates/columns2.mustache
+++ b/theme/boost/templates/columns2.mustache
@@ -68,7 +68,7 @@
                     <div> {{{ output.region_main_settings_menu }}} </div>
                 </div>
                 {{/hasregionmainsettingsmenu}}
-                <section id="region-main" {{#hasblocks}}class="has-blocks mb-3"{{/hasblocks}}>
+                <section id="region-main" {{#hasblocks}}class="has-blocks mb-2"{{/hasblocks}}>
 
                     {{#hasregionmainsettingsmenu}}
                         <div class="region_main_settings_menu_proxy"></div>
diff --git a/theme/boost/templates/core/block.mustache b/theme/boost/templates/core/block.mustache
index 8eb1abbd8996d..7123185031241 100644
--- a/theme/boost/templates/core/block.mustache
+++ b/theme/boost/templates/core/block.mustache
@@ -20,7 +20,7 @@
 
 {{! Start Block Container }}
 <section id="{{id}}"
-     class="{{#hidden}}hidden{{/hidden}} block block_{{type}} {{#hascontrols}}block_with_controls{{/hascontrols}} card mb-3"
+     class="{{#hidden}}hidden{{/hidden}} block block_{{type}} {{#hascontrols}}block_with_controls{{/hascontrols}} card mb-2"
      role="{{ariarole}}"
      data-block="{{type}}"
      {{#arialabel}}