Power Platform Community Forum Thread Details

Hi Team,

I am generating a notification message using a script (HTML / Adaptive Card / message payload) and applying custom styles (background color, fonts, layout, buttons, etc.).

However, the actual output I receive does not reflect the styles I applied. Instead, it renders in a default/light theme format (see first screenshot), while I am expecting an output similar to the styled version (see second screenshot).

What I am trying to achieve:

Styled notification card (dark background, custom button styling, proper spacing)

Consistent rendering across the platform

What is happening instead:

Styles are ignored or overridden

Message renders with default formatting only

Questions:

Are there any style limitations or restrictions for messages/cards in this platform?

Does the platform strip or override custom CSS/styles?

Is there a recommended way (e.g., Adaptive Cards schema, supported properties) to achieve this exact UI?

Are themes (light/dark) controlled by the client rather than the message itself?

I’ve attached screenshots of the current output vs expected output for reference.

Any guidance or best practices would be greatly appreciated.

Categories:

General topics

Hi ,
In Microsoft Teams, custom CSS/HTML styles are intentionally limited. Teams sanitizes HTML and strips unsupported styles, so background colors, fonts, and layout overrides you include in a payload usually don’t apply. Adaptive Cards don’t support arbitrary CSS either. Styling is driven by the Adaptive Card schema and the host’s theming rules, not by custom CSS you send, and Teams controls light/dark themes on the client side. To get styled UI, use supported Adaptive Card properties (containers, text styles, spacing, accent colors) and test in the Teams client because themes and rendering differ by platform.

Here’s the official reference on Teams card formatting and limitations:

https://learn.microsoft.com/microsoftteams/platform/task-modules-and-cards/cards/cards-format

https://learn.microsoft.com/microsoftteams/platform/bots/how-to/format-your-bot-messages