scale-color $lightness must use $secondary for dark themes

[akshayutture-augment]

Test 7

---

Replicated from ai-code-review-evaluation/discourse-greptile#7

[greptile-apps]

Your free trial has ended. If you'd like to continue receiving code reviews, you can add a payment method here.

[akshayutture-augment]

@greptileai

[greptile-apps]

Greptile Overview

Confidence Score: 3/5

• This PR contains a critical logic error that will cause incorrect color rendering in dark themes
• The implementation is mostly correct with consistent application of the dark-light-choose pattern across 32 files. However, there is a critical bug on line 291 of app/assets/stylesheets/desktop/topic-post.scss where the lightness value was incorrectly changed from 30% to 70%, which will cause the wrong color to be displayed in light themes. This is a definite visual bug that needs fixing before merge.
• Pay close attention to app/assets/stylesheets/desktop/topic-post.scss line 291 - contains incorrect lightness value that will cause visual bugs

Important Files Changed

File Analysis

Filename	Score	Overview
app/assets/stylesheets/desktop/topic-post.scss	2/5	Replaces scale-color with dark-light-choose for dark theme support, but contains critical lightness value error on line 291
app/assets/stylesheets/common/admin/admin_base.scss	5/5	Correctly wraps scale-color with dark-light-choose and properly inverts lightness values for dark theme support
app/assets/stylesheets/common/base/_topic-list.scss	5/5	Correctly implements dark theme support by wrapping scale-color with dark-light-choose and inverting lightness values
app/assets/stylesheets/common/base/discourse.scss	5/5	Updates coldmap color classes with proper dark theme support using inverted lightness values
app/assets/stylesheets/common/base/header.scss	5/5	Properly implements dark theme support for header elements with correct lightness inversions

Sequence Diagram

sequenceDiagram
    participant Dev as Developer
    participant SCSS as SCSS Files
    participant Func as dark-light-choose()
    participant Theme as Theme Engine
    participant Browser as Browser

    Dev->>SCSS: Update scale-color() calls
    SCSS->>SCSS: Wrap with dark-light-choose()
    Note over SCSS: Original: scale-color($primary, $lightness: X%)
    Note over SCSS: New: dark-light-choose(scale-color($primary, $lightness: X%), scale-color($secondary, $lightness: (100-X)%))
    
    SCSS->>Func: Pass light & dark theme values
    Func->>Func: Check brightness($primary) vs brightness($secondary)
    
    alt Light Theme (primary darker)
        Func->>Theme: Return first param (primary-based)
    else Dark Theme (primary lighter)
        Func->>Theme: Return second param (secondary-based)
    end
    
    Theme->>Browser: Apply computed color values
    Browser->>Browser: Render with theme-appropriate colors

Loading

[greptile-apps]

_{32 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

logic: Incorrect lightness inversion - original was $lightness: 30% on $primary, but changed to $lightness: 70% on $primary for light theme. Should preserve the original lightness value.

Suggested change

	color: dark-light-choose(scale-color($primary, $lightness: 70%), scale-color($secondary, $lightness: 30%));
	color: dark-light-choose(scale-color($primary, $lightness: 30%), scale-color($secondary, $lightness: 70%));

Prompt To Fix With AI

This is a comment left during a code review.
Path: app/assets/stylesheets/desktop/topic-post.scss
Line: 291:291

Comment:
**logic:** Incorrect lightness inversion - original was `$lightness: 30%` on `$primary`, but changed to `$lightness: 70%` on `$primary` for light theme. Should preserve the original lightness value.

```suggestion
      color: dark-light-choose(scale-color($primary, $lightness: 30%), scale-color($secondary, $lightness: 70%));
```

How can I resolve this? If you propose a fix, please make it concise.