Version menu: show icon when page is missing (etcd-io#544)

assets/scss/_styles_project.scss

@@ -213,7 +213,7 @@
 // add icon to signify that a link is external
 // from https://fontawesome.com/v5.15/icons/external-link-alt?style=solid
 
-.td-content a[href^="http://"]:after, 
+.td-content a[href^="http://"]:after,
 .td-content a[href^="https://"]:after {
   @extend .fas;
   font-size: 50%;
@@ -228,54 +228,27 @@
 }
 
 // ************************************
-
-// Styles for icon in version menu
-
+// Version menu
 // ************************************
 
-// style options in Versions drop down on the upper right of the docs so that it's clear if a doc exists for a particular version as not all docs exist in all versions
-
-//  establish fontawesome on dropdown:after
-
-a.dropdown-item:after {
-
-  font-family: 'Font Awesome\ 5 Free';  
-  position: relative;
-  bottom: 1px;
-  padding: 0 3px;
-  font-size: .7rem;
-
-}
-
-// Document icon is from https://fontawesome.com/v5.15/icons/file-alt?style=solid and signifies a doc exists in a particular version
-
-a.dropdown-item[href*="/docs/"] {
-
+.cncf-vers-menu--item {
   &:hover {
-    background: #a0d0ff linear-gradient(180deg, #1f6897, #1f6897) repeat-x;
-    color: #fff;
-  }
-
-  &:after {
-    content: "\f15c";
+    background: $primary;
+    color: white;
   }
 }
 
-// Remove the doc icon from the version numbers in the dropdown that don't have a corresponding doc. 
-// ~= means that the href value ends in the string specified. Maintainers will have to add new versions as they come out if there aren't docs for that version.
-a.dropdown-item[href~="/docs/v2.3/"], 
-a.dropdown-item[href~="/docs/v3.1/"], 
-a.dropdown-item[href~="/docs/v3.2/"], 
-a.dropdown-item[href~="/docs/v3.3/"], 
-a.dropdown-item[href~="/docs/v3.4/"],
-a.dropdown-item[href~="/docs/v3.5/"] {
-
+.cncf-vers-menu--item__not-found {
+  color: $gray-600;
   &:hover {
-    background:#accff3 linear-gradient(180deg, #deeaf7, #e3ecf5) repeat-x;
-    color: #222;
+    background: lighten($primary, 60%);
+    color: $gray-900;
   }
-
   &:after {
-    content: "";
+    @extend .fas;
+    font-size: .8rem;
+    padding-left: 6px;
+    content: fa-content($fa-var-home);
+    color: lighten($primary, 15%);
   }
 }