To give an explanation for that line, the min function is being used to make all the spaces fit on a phone screen. On the desktop, the vw and vh values will normally be larger, and it will use the px values. But on a phone, the smallest value will sometimes be a vw or vh value, which are defined as percentages of the view width or view height. If a browser does not support the min function or vw/vh units, it will default to the pixel unit, which is not even an issue on desktops, though it may stop some older phones from fitting the diagram on the screen.
To give an explanation for that line, the min function is being used to make all the spaces fit on a phone screen. On the desktop, the vw and vh values will normally be larger, and it will use the px values. But on a phone, the smallest value will sometimes be a vw or vh value, which are defined as percentages of the view width or view height. If a browser does not support the min function or vw/vh units, it will default to the pixel unit, which is not even an issue on desktops, though it may stop some older phones from fitting the diagram on the screen.