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Which is the best way (without using display: flex) to center the container and its contents

I had an issue not getting the container to stay in the middle, there for if you shrink the page it will not stay centered until it reaches 500px

I found adding the icons properly difficult as I have never worked with that format before, I've only ever known font awesome therefore I left them out

The most difficult thing was mixing up margin with padding, something I gained a habit of doing. Causing the border-radius to look not symmetrical.