How to center and crop an image to always appear in square shape with CSS

when we set the img‘s left and right (or: top and bottom) coordinates to be -100% (of the containing div), the overall allowed width (or: height) of the img, can be at most 300% of the containing div‘s width (or: height), because it’s the sum of the div‘s width (or: height) and the left and right (or: top and bottom) coordinates.Below is an example:

    width: 200px;
    height: 200px;
    overflow: hidden;
    margin: 10px;
    position: relative;
img {
    position: absolute;
    margin: auto; 
    min-height: 100%;
    min-width: 100%;

    /* For the following settings we set 100%, but it can be higher if needed 
    See the answer's update */
    left: -100%;
    right: -100%;
    top: -100%;
    bottom: -100%;