Markup
 <div class="sb-form-control">
   <label class="sb-label" for="dropdown-id-disabled">Choose an option</label>
   <div class="sb-dropdown " id="dropdown-id-disabled">
     <div class="sb-dropdown__button sb-form-control__input sb-form-control__input--icon-right">
      <button class="sb-input" aria-label="Choose an option" disabled aria-expanded="false">
        Choice 1
      </button>
      <svg class="sb-icon" viewBox="-5 -5 16 16"><path d="M0 0l3.5 4L7 0H0"></svg>
     </div>
     <ul class="sb-dropdown__menu" role="listbox">
       <li class="sb-dropdown__menu-item" tabindex="0" role="option">Choice 1</li>
       <li class="sb-dropdown__menu-item" tabindex="0" role="option">Choice 2</li>
       <li class="sb-dropdown__menu-item" tabindex="0" role="option">Choice 3</li>
     </ul>
   </div>
 </div>
Source: components/_dropdown.scss, line 293