How long can HTML and CSS be fully mastered?

Question

First I want to apologize for my English is not the My main language, I work advertising and for my work the basic HTML and CSS will be modified since for my work sometimes I have to modify the color of a landing page, text or images. But I have never studied it completely

Answer 1

Time required is directly proportional to the effort you put in.

You could be super hardworking and master both in 1 month or you could stretch the time to years by being lazy.
It depends on you.

Answer 2

1 mnth

Answer 3

I think that it will take at least a year to master it to some extent. Whoever claims anything shorter has to ask himself what means good.

Answer 4

5 months

As you spend 4-5 hours each day learning and in a month you can be recognized to have mastered in 1 material ( in few weeks to practice program code), so that in a total of 5 months you can master HTML, CSS, PHP, MySQL, and JavaScript.