> For the complete documentation index, see [llms.txt](https://chaoses-ib.gitbook.io/directory-opus/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chaoses-ib.gitbook.io/directory-opus/guan-fang-shou-ce/readme.zh-9/readme.zh/readme.zh/colors.md).

# Colors

In a toolbar or menu button, you can use the **@color** modifier to set the text and background colors of the button dynamically using the evaluator.

As a very basic example, `@color:=text="#000000"; back="#ff0000";` would set the text color to black and the background color to red.

To specify separate colors for light and dark modes, you could use something like this:

`@color:=SysInfo("DarkMode") ? { text="#ff0000"; back="#ffff00"; } : { text="#0000ff"; back="#00ffff"; }`

![](https://github.com/Chaoses-Ib/DirectoryOpus/blob/main/Manual/evaluator/applicable_contexts/functions/page%3Estandard_variables\&nodate\&nouser\&nofooter)

The [SysInfo](/directory-opus/manual/reference/evaluator/sysinfo.md) function can also be useful for testing global properties, like whether Opus is in dark or light mode.

The evaluator clause should set the value of the `text` and `back` variables. You can specify either a hex color string ("#RRGGBB") or decimal color string ("RRR,GGG,BBB"). You can also return "default" to get the button's defaults, or "none" to get the toolbar's defaults.


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