Bootstrap 内置了几种预定义的按钮样式，每种样式都有自己的语义目的，并添加了一些额外的按钮includes several predefined button styles, each serving its own semantic purpose, with a few extras thrown in for more control.
#!/usr/bin/python3 print("Hello, World!")尝试一下一键复制
#!/usr/bin/python3 print("Hello, World!")