Failed to install it use brew or script

[ljk5403]

When I tried to use brew cask install WebPQuickLook to install WebPQuickLook, I got this error:

==> Downloading https://raw.githubusercontent.com/emin/WebPQuickLook/master/WebpQuickLook.tar.gz
##O=#  #
curl: (60) SSL: no alternative certificate subject name matches target host name 'raw.githubusercontent.com'
More details here: https://curl.haxx.se/docs/sslcerts.html

curl failed to verify the legitimacy of the server and therefore could not
establish a secure connection to it. To learn more about this situation and
how to fix it, please visit the web page mentioned above.
Error: Download failed on Cask 'webpquicklook' with message: Download failed: https://raw.githubusercontent.com/emin/WebPQuickLook/master/WebpQuickLook.tar.gz

What I know is that I used SOCKS proxy, and I am sure brew and the proxy is working fine.

I could not also use the curl -L https://raw.github.com/emin/WebPQuickLook/master/install.sh | sh to install, with error:

curl: (7) Failed to connect to raw.githubusercontent.com port 443: Connection refused

when I didn't use proxy. Since now I am in Mainland China, it is acceptable, and after set up SOCKS proxy, I got:

curl: (60) SSL: no alternative certificate subject name matches target host name 'raw.githubusercontent.com'
More details here: https://curl.haxx.se/docs/sslcerts.html

curl failed to verify the legitimacy of the server and therefore could not
establish a secure connection to it. To learn more about this situation and
how to fix it, please visit the web page mentioned above.

which is just like the error in brew.

So maybe the install.sh has some problems with proxy? I am not sure, please help me! Thanks a lot.