2019 CSS portuguese translation (#3475)

* Create css.md

* Update css.md

* Update css.md

* Update css.md

* Update css.md

* Update css.md

* Update css.md

fixed inconsistent blank line

* Update css.md

Fix Una bio and Argyleink bio.

* Fix build error

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Co-authored-by: Barry Pollard <barrypollard@google.com>

Author: HakaCode