fmpq.com
源代码：
点击运行
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> </head> <body> <h3> h3 元素</h3> <h2> h2 元素</h2> <script> document.querySelector("h2, h3").style.backgroundColor = "red"; </script> </body> </html>
运行结果