After installation, Go to, Settings >> General Settings in that go to Backend Theme Colors and select checkbox Allow Custom Colors For Backend Theme, to set custom colors for backend theme. You can select any color from color picker as you can see in screenshot.

After color setup, you can see effect on navigationbar and it's menu item and hover effect also

For frontend theme color, Go to, Settings >> General Settings in that go to Website menu, here you can see Frontend Theme Colors and select checkbox Allow Custom Colors For Frontend Theme, to set custom colors for frontend theme. You can select any color from color picker. You can set color for navigationbar background color, navigationbar menu item colors and text colors and you can set text and background colors button like primary button, Success button, warning button etc.

After color setup, you can see effect on navigationbar and it's menu item and hover effect also