JSFiddle - React, Tailwind, and code Playground

HTML

<select>
    <option>first one</option>
    <option>normal</option>
    <option>normal</option>
    <option>normal</option>
</select>

CSS

select { font-style: italic;   } 
select option  {
  font-style: normal;  
}
select option:first-child {
  font-style: italic;   
}