How do I center button both vertically and horizontally?

Question

I tried several ways, including:
- display: inline-block; + margin: auto;
- put it into separate "div" and set it's margin to "auto";
- in some other forum, I've found that button should be aligned as text. I tried "vertical-align" - it didn't work also.
Best I could achive is only horizontal center align.

p.s.: I work in Mozilla. Maybe there is some special selector for it?

Answer 1

https://code.sololearn.com/WwrKexflTTXb/?ref=app

Answer 2

*{
margin: 0px;
padding: 0px;
};

#button {
margin: 10px;
padding: 10px;
text-align: center;
};

Answer 3

thank you friends!;)