<html><head><style media="screen AND (max-width:500px)" type="text/css">a { background-color: grey; color: white; padding: 15px; font-size:40px;}</style><style media="screen AND (min-width:500px)" type="text/css">a { color: red; font-weight: 400; font-size:40px;}</style></head><body><h1>style media 属性</h1><p>请调整窗口尺寸，查看链接样式的变化：</p><p><a href="/index.html" target="_blank">W3School</a></p></body></html>