revert to small icon

src/components/Header.vue

@@ -29,11 +29,11 @@
            width="100%"
            
            plain
-           medium
+           small
            
            
            @click="$parent.collapsed=!$parent.collapsed">
-           <v-icon medium>{{$parent.collapsed ? 'expand_more': 'expand_less'}}</v-icon></v-btn></span> 
+           <v-icon small>{{$parent.collapsed ? 'expand_more': 'expand_less'}}</v-icon></v-btn></span> 
   </div>
 </template>