Fix mobile view errors

Author: Dhruvi16

themes/vocabulary_theme/templates/authors.html

@@ -8,7 +8,7 @@
       <h1 class="container">Authors</h1>
     </div>
     <div class="authors-list container">
-      <div class="columns is-multiline">
+      <div class="columns is-multiline is-mobile">
         {{ render_authors(this) }}
       </div>
     </div>

themes/vocabulary_theme/templates/macros/authors.html

@@ -2,7 +2,7 @@
 
 {% macro render_authors(authors) %}
   {% for author in site.query(authors.path) %}
-    <div class="author column is-2">
+    <div class="author column is-6-mobile is-2-desktop">
       {% if author.md5_hashed_email %}
         <figure class="image profile">
           <img class="profile" src="https://secure.gravatar.com/avatar/{{ author.md5_hashed_email }}?size=200" alt="gravatar" />