How to restore the default theme in Windows 10.7 great bright color themes for windows 10 you should not miss this summer.You can save these settings into a new theme file to use and send to your friends. Windows 10 allows users to create their own theme with background desktop, window borders and color accents for the custom Start menu. You want to change the look of the desktop and windows in Windows without 'crashing'? You can do that on Windows 10.