[White Label - Atoz]: Luminosity ratio of Atoz border is less than required ratio of 3:1.

Is it an issue related to Adaptive Cards?

No.

What is the PWD impact?

Low‑vision users may struggle to identify the boundaries of the Atoz control due to poor contrast. This makes it difficult to understand what is interactive or selectable, which can slow navigation and cause confusion.

What browsers and screen readers do this issue affect?

Others

Are there any code-based customization done to Web Chat?

No, I am using Web Chat without any customizations except "styleOptions".

What version of Web Chat are you using?

Latest production

Which area does this issue affect?

Contrast ratio

What is the public URL for the website?

No response

How to reproduce the issue?

Repro Steps:

1. Open URL: https://compulim.github.io/webchat-loader/ and sign in using valid credentials.
2. Navigate to web chat page and select 4.18.1-main.20240927.ea7a875 (30/9/2024) version and then select mockBot link under present label and then select open web chat in new window link at bottom.
   3.Navigate to white label experience chat page and type atoz word in type your message text box.
3. Response will appear.
4. Navigate to the Atoz prompt border.
5. Observe an issue that Luminosity ratio of Atoz border is less than required ratio of 3:1.

What do you expect?

The element should maintain at least a 3:1 non‑text contrast ratio between the border and adjacent background.

What actually happened?

Luminosity ratio of Atoz border is less than required ratio of 3:1.

Do you have any screenshots or recordings to repro the issue?

Did you find any DOM elements that might have caused the issue?

No response

MAS reference

No response

WCAG reference

https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast

WAI-ARIA reference

No response

Adaptive Card JSON

Additional context

No response

Start by reproducing the issue at the webchat-loader URL using the listed 4.18.1-main version, then inspect the Atoz prompt border and its surrounding background. Use the WCAG non-text contrast reference to verify the border reaches at least a 3:1 ratio, and confirm the result in the white-label experience.