![](https://csdnimg.cn/release/download_crawler_static/89376613/bg1.jpg)
以下是一个简单的前端 HTML 和 CSS 代码示例: ```html <!DOCTYPE
html> <html> <head> <style> .box { width: 200px; height: 100px;
background-color: lightblue; border: 2px solid black; } </style>
</head> <body> <div class="box"></div> </body> </html> ```