<html><head><style> #myDIV { width: 300px; height: 300px; background-color: coral; color: white;}</style></head><body><h1>HTML Style 对象</h1><h2>backgroundColor 属性</h2><p>请点击“试一试”按钮，将 DIV 元素的 backgroundColor 属性设置为 “lightblue”：</p><button onclick="myFunction()">试一试</button><div id="myDIV"> <h1>Hello</h1></div><script>function myFunction() { document.getElementById("myDIV").style.backgroundColor = "lightblue";}</script></body></html>