UX: Fix mobile PM nav for regular users (#14007)

UX: Fix mobile PM nav for regular users (#14007)

diff --git a/app/assets/stylesheets/mobile/user.scss b/app/assets/stylesheets/mobile/user.scss
index 47ff10b..04da05b 100644
--- a/app/assets/stylesheets/mobile/user.scss
+++ b/app/assets/stylesheets/mobile/user.scss
@@ -32,7 +32,7 @@
 
   // specific to messages
 
-  .user-messages.user-messages-inboxes {
+  .user-messages {
     grid-row-start: 2;
     grid-column-start: 1;
     grid-column-end: 3;
@@ -41,6 +41,15 @@
     grid-template-columns: 1fr 1fr;
     gap: 16px;
 
+    &.user-messages-inboxes {
+      // when there are multiple inboxes
+      .messages-nav {
+        grid-column-start: 2;
+        grid-column-end: 3;
+        grid-row-start: 1;
+      }
+    }
+
     + .user-additional-controls {
       grid-row-start: 2;
       grid-column-start: 1;
@@ -63,12 +72,6 @@
     }
   }
 
-  .messages-nav {
-    grid-column-start: 2;
-    grid-column-end: 3;
-    grid-row-start: 1;
-  }
-
   .new-private-message {
     grid-row-start: 1;
     grid-column-start: 2;

GitHub sha: f848f6cbb63585ec2ad9d07cc81e0ba6358cd64a

This commit appears in #14007 which was approved by CvX and OsamaSayegh. It was merged by awesomerobot.