Ask HN: Can you program without an Internet connection?

I ran a little experiment the other day to see how I would get on coding without an Internet connection. I was doing a bit of web development, mostly frontend stuff, and was proud of how many obscure HTML elements I was using like <DETAILS> and <CITE> etc. Then the urge to open a browser came within 10 minutes of coding. I wanted to code a hamburger menu, but didn't want to reinvent the wheel. Specifically I wanted the hamburger menu to work with CSS only so was looking for a snippet of code that done that, but had no Internet.

I was genuinely asking myself: 'Am I even a competent developer if I have to use the Internet every five minutes to code?'

How do you cope with this feeling, of tapping into the Internet hive mind to code properly?