Squares view.

[extempl]

@some1else For squares you could use 1px gif with width: 100%: https://jsfiddle.net/extempl/t5hamwo3/
Also, try generate all html, it will look much cleaner.

[extempl]

Possibly, this would also look better with table use - then you will need to put those images only on the very top and left cells.

[some1else]

Yeah the base data structure could fit in a table. Thanks for the feedback