Revert recent repo changes

public/assets/styleguide.upstream.css

@@ -3057,7 +3057,7 @@ section + section {
 
 .sg-left-navigation-pattern__layout {
   display: flex;
-  align-items: flex-start;
+  align-items: stretch;
   gap: 0;
   width: 100%;
   min-width: 0;
@@ -3093,7 +3093,8 @@ section + section {
 
 @media (min-width: 768px) {
   .sg-left-navigation-pattern__group-card--navigation .sg-tab-button-group[data-component-variant="linksmenu-items"] {
-    justify-content: flex-start;
+    height: 100%;
+    justify-content: center;
   }
 }
 
@@ -3136,6 +3137,21 @@ section + section {
   flex-direction: column;
 }
 
+.sg-card-list-page-drawer-backdrop {
+  position: fixed;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.45);
+  opacity: 0;
+  pointer-events: none;
+  transition: opacity 220ms ease;
+  z-index: 999;
+}
+
+.sg-card-list-page-drawer-backdrop[data-open="true"] {
+  opacity: 1;
+  pointer-events: auto;
+}
+
 .sg-card-list-page-drawer {
   position: fixed;
   top: 0;
@@ -4368,4 +4384,3 @@ section + section {
   color: var(--text-typography-preview);
   margin-top: 0;
 }
-