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114. What is CSS pixel and device pixel?

Yes, I do know the definition of CSS pixel and device pixel.

CSS pixel refers to the unit of measurement used in CSS to define the size of an element on a web page. It is also known as a logical pixel because its size is based on the resolution of the display screen and not the size of the physical pixel of the device.

On the other hand, a device pixel refers to the smallest unit that makes up a physical display screen. The device pixel ratio (DPR) is the ratio between the physical pixel and CSS pixel. It tells us how many physical pixels are used to display each CSS pixel. For example, if the DPR is 2, then two physical pixels are used to display each CSS pixel.

The devicePixelRatio property is used to retrieve the ratio between the physical pixel and CSS pixel on a device. It is commonly used in responsive web design to ensure that the web page is displayed correctly on devices with different pixel densities.