[GUI Plugin] Lectrix themes

[pan4ratte]

Lectrix themes gives calibre the light and dark themes of Lectrix, a free, open-source PDF editor. The colors come from Neo's light and Midnight themes for Obsidian, tinted toward Lectrix blue. Calibre uses the theme that matches its mode (light, dark, or following the system), and switches when the mode changes.

What it does

• Sets calibre's light and dark colors (Look & feel → Adjust colors) to Lectrix's. The e-book viewer and the book editor use these colors too.
• Styles what the colors alone can't reach: the title bar, fields, dropdowns, buttons, menus, tooltips, scrollbars and the book list's column headers.
• The Tag browser and Book details end in a thin line where they meet the book list, as Lectrix's side panes do.
• Fixes two things in calibre's dark mode: the Tag browser's hover and the book list's current cell, which calibre draws brighter than the selection, with black text.

A companion plugin with the same styling for the book editor, plus Lectrix syntax themes, is available from the GitHub releases for now.

Installation
Preferences → Plugins → Get new plugins, find Lectrix themes, install it and restart calibre. Then, in Preferences → Look & feel → Main interface, make sure "User interface style" is calibre. Calibre ignores custom colors with the "System" style.

Turning it off
Untick Use the Lectrix theme in Preferences → Plugins → Lectrix themes → Customize plugin. The colors you had before come back, in both modes, and all the styling goes. Calibre doesn't tell plugins when they're removed, so untick this before removing the plugin. If you already removed it, use Adjust colors → Restore defaults.

Requirements
calibre 7 or newer. The title bar colors and the round corners of menus need Windows 11. Developed and tested on Windows 11.

Source code
github.com/pan4ratte/calibre-lectrix-themes, GPL v3.

Version history

Spoiler:

1.1.0

• The Tag browser and Book details end in a thin line where they meet the book list, as in Lectrix.
• Scrollbars, column headers and dropdowns look like Lectrix's.
• Menus and dropdown lists have round corners (Windows 11).

1.0.0

• First release.