<label for="vacation-dest">Vacation Destinations</label>
<select name="vaction-dest" id="vacation-dest">
    <optgroup label="East Coast - Australia">
        <option value="NSW">New South Wales</option>
        <option value="QLD">Queensland</option>
        <option value="TAS">Tasmania</option>
        <option value="ACT">Australian Capital Territory</option>
        <option value="VIC">Victoria</option>
    </optgroup>
    <optgroup disabled label="West Coast - Australia">
        <option value="WA">Western Australia</option>
        <option value="NT">Northern Territory</option>
        <option value="SA">South Australia</option>
    </optgroup>
</select> 

body {
  color: #333;
  font-family: Tahoma, sans-serif;
  font-size: 16px;
  line-height: 1.25;
}