fmpq.com
源代码：
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<!DOCTYPE html> <html> <head> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta charset="utf-8"> <title>Fmpq教程(fmpq.com)</title> <style> body { background-color: lightgreen; } @media only screen and (orientation: landscape) { body { background-color: lightblue; } } </style> </head> <body> <p>重置浏览器大小，当文档的宽度大于高度时，背景会变为浅蓝色。否则为浅绿色。</p> </body> </html>
运行结果