SideBar Bottom Background Color

[DarrellBrogdon]

Description

Sorry to submit this as a bug but, I don't see anything in the documentation or examples. I'm trying to set background color of a SideBar bottom widget.

Steps To Reproduce

1. Create a MacosWindow with a SideBar which itself has a bottom: widget.
2. There doesn't seem to be a way to set the background color, though screenshots and such seem to indicate that its possible

Expected behavior

I would expect a backgroundColor: or style: property.

[✓] Flutter (Channel stable, 3.35.7, on macOS 26.0.1 25A362 darwin-arm64, locale en-US)
[✓] Android toolchain - develop for Android devices (Android SDK version 36.0.0-rc3)
[✓] Xcode - develop for iOS and macOS (Xcode 26.1)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2025.1)
[✓] VS Code (version 1.105.1)
[✓] Connected device (2 available)
    ! Error: Browsing on the local area network for xxx. Ensure the device is unlocked and attached with a cable or associated with the same local area network as this
      Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
    ! Error: Browsing on the local area network for xxx. Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
[✓] Network resources

• No issues found!