For viewport, you can limit the size presented to the page to a few sizes with different aspect ratios. Browsers can simply rescale the page to the actual wind

For viewport, you can limit the size presented to the page to a few sizes with different aspect ratios. Browsers can simply rescale the page to the actual window size for display on the screen. That also works for font rendering. If users decide they want pixel-perfect display, they can either resize the window to one of the allowed sizes or disable this feature for a specific page.