Container-fluid class

I used the container-fluid class, but my page still doesn’t open in a suitable size on the phone

When you start using fixed px width for margins, paddings, widths, etc. in your CSS… it’s likely only going to look good at one resolution and fail when viewed on a smaller display screen.

For example: Your css

  width: 650px;
  border-radius: 10px;

What happens if somebody tries to view the site on a mobile phone display that’s only 360px wide?

Also, what if you have a logo? Will that also display at 650px?
All your images will display at 650px

would the margin: auto; give me the same good looking for site?