[code-reflection] RFR: MNISTDemo UI tweak [v2]

[Adam Sotona]

> MNISTDemo UI adjusted.
> 
> ![screenshot](https://github.com/user-attachments/assets/a9eaca28-13d7-45f4-9fb3-97f83bff7f38)

Adam Sotona has updated the pull request incrementally with one additional commit since the last revision:

  added colors

-------------

Changes:
  - all: https://git.openjdk.org/babylon/pull/327/files
  - new: https://git.openjdk.org/babylon/pull/327/files/d9d98e08..6799f648

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=327&range=01
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=327&range=00-01

  Stats: 4 lines in 1 file changed: 3 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/babylon/pull/327.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/327/head:pull/327

PR: https://git.openjdk.org/babylon/pull/327