:optional 예제
<style> input:required {background-color: yellow;} input:optional {background-color: silver;} </style> <h3>홈짱닷컴 Homzzang.com</h3> <p>아이디 필수: <input required></p> <p>닉네임 선택: <input></p> 결과보기
<style>
input:required {background-color: yellow;}
input:optional {background-color: silver;}
</style>
<h3>홈짱닷컴 Homzzang.com</h3>
<p>아이디 필수: <input required></p>
<p>닉네임 선택: <input></p>
결과보기