[FEATURE] User message background highlighting makes text harder to read in dark terminal themes

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Since a recent update (around October 2025, version 2.0.14), user messages are displayed with a white/light background box in the terminal output. This creates poor contrast and readability issues when using dark terminal themes.

Expected Behavior

User messages should either:

1. Use the terminal's default background color (no highlighting box), or
2. Respect the terminal's color scheme (dark background for dark themes)

Actual Behavior

User messages appear in a white/light background box regardless of the terminal theme, which is jarring and hard
to read in dark-themed terminals.

Environment

• Claude Code Version: 2.0.14
• OS: Windows (CMD/PowerShell)
• Terminal Theme: Dark

This UI change appeared to happen between October 2nd and October 13th, 2025. The previous behavior (no background highlighting or theme-aware highlighting) was more comfortable for users with dark terminal themes.

Thank you for considering this feedback!

<img width="1099" height="500" alt="Image" src="https://github.com/user-attachments/assets/dcb50ace-f8ec-4326-b623-bf9b624d7dec" />

Proposed Solution

Expected Behavior

User messages should either:

1. Use the terminal's default background color (no highlighting box), or
2. Respect the terminal's color scheme (dark background for dark themes)

Suggested Solution

• Add a configuration option to disable message background highlighting
• Or make the highlighting color adapt to the terminal's color scheme
• Or revert to the previous UI behavior

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

Configuration and settings

Use Case Example

_No response_

Additional Context

_No response_