If you click on the little colored icon next to color codes in Chrome DevTools you get a nice color picker. This comes in very handy to play with select the best colors for your design. By default the eye dropper will also be active, meaning you can sample any color on the current page:

Change color mode

color illustration for: Change color mode

You can also easily change color modes between HEX, RGBA and HSLA:

Play with the hue and opacity

Then again, you can play around with different hues and opacity levels:

Color palettes

And finally, you can access color palettes. By default colors from your page are show in the palette, but you can create a custom color palette or use the Material Design color palette: