* Translate challenge subtitles and example challenge text to Spanish
* Corrected errors in syntax and punctuation
* Multiple corrections of it/s to its plus other grammar corrections
* Correction and added paragraph to CSS Flex article
* Corrected my own typo
* Corrected capitalization, American spellings and typos
Fixed problem with math for number of people, text says 1 in 20 people have color blindness and then it later says that is almost 1 billion people... that would be true if population of earth was 20 billion.
Also fixed one spelling mistake that I noticed.
Robert Samu
S.Hale
Nenad Anđelković
Mrugesh Mohapatra