How to make circular background using css?

css

Solution

Keep it simple:

.circle
{
    border-radius: 50%;
    width: 200px;
    height: 200px; 
}

Width and height can be anything, as long as they're equal

Problem

I need make something like this. and I want to do it for a `<div></div>` which has `width` in `%` I can do this by using an image and adding another `div` inside and `z-index`. But I want to know if it's possible to make in this circle in backgroud using css.

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