Bootstrap class updates to ensure better mobile compatibility

app/templates/verse.hbs

@@ -1,7 +1,7 @@
 <div class="container">
   <h1>{{model.reference}}</h1>
   <div class="row">
-    <div class="col-12">
+    <div class="col-12 mt-4 mb-3">
       <h4>ULB</h4>
       <p>{{model.ulbText}}</p>
       <h4>Greek</h4>
@@ -9,10 +9,10 @@
     </div>
   </div>
   <div class="row">
-    <div class="col-6">
+    <div class="col-sm-6 mt-4">
       <Words::WordTable @model={{model.words}} />
     </div>
-    <div class="col-6">
+    <div class="col-sm-6 mt-4">
       {{outlet}}
     </div>
   </div>