Do you need a CMYK code instead of HWB?
Dopely's Converter can do it for you.
If the color you want for your print design is in the css4 page. This is not a big problem. You can find the equivalent CMYK values just by entering the desired HWB values of the color in this tool and use it for the desired design!
This color model is very similar to HSL. HWB refers to Hue, Whiteness and Blackness. You can adjust the white and black values of each color with this model. This color model is commonly used in css4.