Vertical centering has always been a fairly elusive goal when dong CSS layouts, but it's actually easier to achieve than you might think. Here are the two simplest methods that I know of to achieve this goal.
A quick line of code to ensure that your WordPress content editor will always land on the HTML tab by default. This will ensure that your HTML tags & attributes are never stripped automatically.
I recently had to create an interview test for a developer who has good skill in PHP, but is not so experienced when it comes to front-end coding. On the front-end side of things, the job they were interviewing for required decent HTML & CSS knowledge. With that in mind I created a little test to evaluate their skills - I'm posting it here for anyone else who needs something similar.