<!DOCTYPE html> <html lang="zh-CN"> <head> <meta charset="UTF-8"> <title>Hello CodeIDE</title> <style> body { font-family: sans-serif; } h1 { color: #4f46e5; } </style> </head> <body> <h1>你好，CodeIDE</h1> <p>在左侧编写代码，点击「运行」即可预览。</p> </body> </html>