html 使用CSS伪类为选择元素添加占位符：4。可能是正确的答案

Posted 2021-05-11

<style>
select:required:invalid {
  color: gray;
}
option[value=""][disabled] {
  display: none;
}
option {
  color: black;
}
</style>

<select required>
  <option value="" disabled selected>Select something...</option>
  <option value="1">One</option>
  <option value="2">Two</option>
</select>