User interface themes
The interface theme defines the appearance of windows, dialogs, buttons, and all visual elements of the user interface. By default, Aqua uses the Darcula theme, unless you changed it during the first run.
Change the UI theme
In the Settings dialog (Control+Alt+S), select Appearance & Behavior | Appearance.
Select the UI theme from the Theme list:
Light: Aqua default light theme
Dark: Aqua default dark theme
Light with Light Header: Default light theme with a light header
Darcula: Alternative dark theme
IntelliJ Light: Traditional light theme for IntelliJ-based IDEs
High contrast: Theme designed for users with color vision deficiency
Select Sync with OS to let Aqua detect the current system settings and use the default dark or light theme accordingly. If your OS is set up to auto-switch between day and night modes, the IDE will automatically toggle between light and dark themes too.
It is also possible to create your own UI themes for Aqua and customize the built-in themes. For more information, refer to IntelliJ Platform SDK Documentation.
Use the quick switcher
Press Control+` or selectfrom the main menu.
In the Switch popup, select Theme, and then select the desired interface theme.
You can map the Theme action to your preferred key combination.