Am I writing the markup and css correctly?

Question

css

Wow, just made a post design. and FIG knows if it's all right or not.
If there are errors somewhere, semantic or something else, please correct them.
Just, just finished with html, css, less and trying to do something.
Do not judge strictly.
And yes, it's kind of a stupid question.
Here is the post design.

Answer 1

if it is displayed as it should, then everything is correct