Merge pull request #17819 from open-craft/tomaszgy/fix_hawthorn_default_theme_issues

Fix styling of navtabs.

lms/static/sass/_header.scss

@@ -11,6 +11,7 @@
   border-bottom: 1px solid theme-color("primary");
   box-shadow: 0 1px 5px 0 rgba(0, 0, 0, 0.1);
   background: theme-color("inverse");
+  line-height: 1.5;
 
   /*
     Logo and course identification block
@@ -102,7 +103,7 @@
             font-weight: $font-weight-normal;
             display: inline-block;
             margin-bottom: -1*$baseline/2;
-            border-bottom: 4px hidden theme-color("dark");
+            border-bottom: 4px solid transparent;
             cursor: pointer;
 
             &.active,

lms/templates/header/navbar-authenticated.html

@@ -39,13 +39,13 @@ from openedx.core.djangoapps.site_configuration import helpers as configuration_
     % endif
     % if show_explore_courses:
       <div class="mobile-nav-item hidden-mobile nav-item nav-tab">
-        <a class="btn" href="${marketing_link('COURSES')}">${_('Discover New')}</a>
+        <a class="tab-nav-link" href="${marketing_link('COURSES')}">${_('Discover New')}</a>
       </div>
     % endif
     % if show_sysadmin_dashboard:
-      <div class="mobile-nav-item hidden-mobile nav-item">
+      <div class="mobile-nav-item hidden-mobile nav-item nav-tab">
         ## Translators: This is short for "System administration".
-        <a class="btn" href="${reverse('sysadmin')}">${_("Sysadmin")}</a>
+        <a class="tab-nav-link" href="${reverse('sysadmin')}">${_("Sysadmin")}</a>
       </div>
     % endif
   </div>
@@ -67,5 +67,3 @@ from openedx.core.djangoapps.site_configuration import helpers as configuration_
     <%include file="user_dropdown.html"/>
   </div>
 </div>
-
-