Reduce size and overlap of result titles

Why these changes are being introduced:

This was suggested by UXWS as a visual design improvement.

Relevant ticket(s):

* [GDT-238](https://mitlibraries.atlassian.net/browse/GDT-238)
* [GDT-215](https://mitlibraries.atlassian.net/browse/GDT-215)

How this addresses that need:

This changes the result titles, authors, and highlights heading
to the suggested sizes.

Side effects of this change:

None.

Author: jazairi

app/assets/stylesheets/partials/_results.scss

@@ -25,15 +25,16 @@
   border-top: 1px solid $brand-primary;
   font-size: $fs-small;
 
-  /* Adding hd-2 styling for order markers to match result titles */
   &::marker {
-    font-size: $fs-xxlarge;
-    line-height: $lh-tight;
+    font-size: 2.5rem;
+    line-height: 1.1;
     font-weight: $fw-bold;
   }
 
   .record-title {
     display: inline;
+    font-size: 2.5rem;
+    line-height: 1.1;
   }
 
   &:hover,
@@ -84,4 +85,9 @@
     -webkit-line-clamp: 3;
     -webkit-box-orient: vertical;
   }
+
+  .inner-heading {
+    font-size: 1.8rem;
+    line-height: 1.1;
+  }
 }

app/assets/stylesheets/partials/_shared.scss

@@ -1,7 +1,7 @@
 .result,
 .full-record {
   .authors {
-    font-size: $fs-large;
+    font-size: 1.8rem;
     font-weight: $fw-bold;
     margin-bottom: 0.6em;
   }

app/views/search/_highlights.html.erb

@@ -1,7 +1,7 @@
 <% highlights = trim_highlights(result) %>
 <% return unless highlights&.any? %>
 
-<h3 class="hd-6">Other fields matching your search:</h3>
+<h3 class="inner-heading">Other fields matching your search:</h3>
 <ul class="list-unbulleted truncate-list">
   <% highlights.each do |h| %>
     <% h['matchedPhrases'].each do |phrase| %>