unordered lists should only have list items as children

opentech/apply/funds/templates/funds/submissions.html

@@ -30,7 +30,9 @@
             <form action="" method="get" class="form form--filters">
                 <ul class="form__filters select2 js-filter-list">
                     {{ filter.form.as_ul }}
-                    <button class="button button--primary" type="submit" value="Filter">Filter</button>
+                    <li>
+                        <button class="button button--primary" type="submit" value="Filter">Filter</button>
+                    </li>
                 </ul>
             </form>
         </div>

opentech/static_src/src/sass/apply/components/_button.scss

@@ -10,11 +10,8 @@
         display: inline-block;
 
         .form--filters & {
-            margin-right: 0;
-
-            @include media-query(tablet-portrait) {
-                flex-basis: 125px;
-            }
+            width: 100%;
+            height: 100%;
         }
     }