Made min width smaller for dynomath

common/lib/xmodule/xmodule/css/capa/display.scss

@@ -158,7 +158,7 @@ section.problem {
           border: 1px solid #e3e3e3;
           @include inline-block;
           @include border-radius(4px);
-          min-width: 300px;
+          min-width: 30px;
         }
       }
     }