出现Failed to connect to github.com port 443

报错如下：

PS C:\Users\ugug\Desktop\a> git clone https://github.com/TryGhost/Casper
Cloning into 'Casper'...
fatal: unable to access 'https://github.com/TryGhost/Casper/': Failed to connect to github.com port 443: Timed out

原因：网不好，不要信网上的鬼话换这换那的。