I would like to modify the web-design of paperui in openhab2 and change the icon

Hi guys
I made a lot of attempts to change the paperui’s web-desige.
I installed openhab2 on ubuntu using apt-get install openhab2.
But I could not find paperui, so I installed smarthome using eclipse and found org.eclipse.smarthom.paperui. I deleted the icon, modified the font color, and then executed openhab2, but it did not work.
In conclusion, I would like to change the paperui icon or font color scheme of openhab2 installed by using apt-get on ubuntu. Please let me know a lot of ways.