<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>picture</title>
</head>
<body>
<picture>
<source media="(min-width: 700px)" srcset="http://ezcode.kr/study/html/img/kitty.jpg">
<source media="(min-width: 500px)" srcset="http://ezcode.kr/study/html/img/mallard.jpg">
<img src="http://ezcode.kr/study/html/img/nature.jpg" alt="동물" style="width=auto;">
</picture>
</body>
</html>