Sleek
Sleek is a modern dark-mode theme for LaunchBox Desktop, built around a Midnight Glass / dark navy style.
Features

Modern dark navy color palette
Redesigned Game Details view

Persistent vertical navigation bar for Home, Images, Info, Achievements, and Related
Cleaner Home/details layout with play controls, metadata, rating, and RetroAchievements status
Improved responsive layout for Info, Images, Achievements, and Related sections
Custom bottom bar for displayed games, RetroAchievements status, music controls, and size controls
Cleaner top bar with search, filters, menu, and window controls

Installation

1. Download and extract the zip.

2. Place the Sleek folder here:

LaunchBox\LBThemes\Sleek

3. Open LaunchBox.

4. Go to:

Tools > Options > Visuals > Theme

5. Select Sleek.

If Windows blocks the included plugin DLL, right-click the DLL, open Properties, and choose Unblock.

Notes

This theme is for LaunchBox Desktop, not Big Box.
For best results, set LaunchBox’s Dialog Theme colors to match the Sleek palette under:
Tools > Options > Visuals > Dialog Theme
Recommended colors:
Accent: #4EA3FF
Highlight: #123A6A
Background: #071425
Border: #1D3A5F
Foreground: #E8EEF7
Contrast: 0.37

Credits
Sleek is based on the Big Details theme, with extensive redesign work.