I'd like to check this out but that web site kills my mobile browser every time. What are they doing?
You can access the content here: https://github.com/ant4g0nist/rudroid
I don't think you're the only blog to do this collapse-by-default code but every blog that does this I always miss the code.
So my suggestion would be to just not collapse. In my own blog I just set a max-height of 600px or something so long code snippets don't get unruly. People can scroll through or go to Github if that gets annoying.
But at least there's no chance of them missing the code in the first place.