#edit-first-container,
#first-container,
#second-first-container,
#second-container {
  display:inline-block;
  width:100%;
}

@media (max-width:767px) {
  fieldset {
     width: 100% !important;
     margin-right: 0 !important;
  }
  .views-exposed-form .form-checkboxes .form-item, 
  .webform-submission-form .form-checkboxes .form-item {
    margin-bottom: 5px !important;
 }
}