No, this is not a real Sinatra error :).
This is the personal homepage of Elad Meidar, a web developer and an entrepreneur specializing in Ruby on Rails. I hang around in Israel, and i am currently having the best time of my life over at Fiverr.com
I am a proud member of RailsBridge, Helping new Rails developers get into our world and also contributed a few Patches to the Ruby on Rails core.
First thing, it helps.
Exactly the same as in Server side languages and client side languages, frameworks are a great improvement (in most cases) to a regular off the board development.
There are a lot of CSS frameworks these days, Noupe guide to CSS framework gathers the best of the guides and tutorials for each of the major frameworks.
I personally tried to use several of them and i guess the 960 CSS framework proven to be the easiest to handle (for me, and i usually don’t do CSS).
You're seeing this error because I think it is funny.