I am working on drop down which is working fine. after i selected option from drop down it background color got changed(lime). now i focus on another option which color got changed(mango). in this scenario both mango and lime color looking same.how to remove selected option background color when focus on other

code:

<select>
  <option value="grapefruit">Grapefruit</option>
  <option value="lime">Lime</option>
  <option value="coconut">Coconut</option>
  <option value="mango">Mango</option>
</select>

select option:hover,
    select option:focus,
    select option:active {
        background: linear-gradient(#000000, #000000);
        background-color: #000000 !important; /* for IE */
        color: #ffed00 !important;
    }

    select option:checked {
        background: linear-gradient(#d6d6d6, #d6d6d6);
        background-color: #d6d6d6 !important; /* for IE */
        color: #000000 !important;
    }