at the bottom. You can change specific background and text colors to your liking and save it as a custom theme. Option 2: Third-Party Visual Styles (Best Appearance)
Websites like DeviantArt are the best sources for Windows 8.1 themes. Popular options include: A minimalist, neutral dark grey theme. dark theme for windows 81
Only download files from reputable community sites to avoid malware. If you'd like to move forward with this, I can help you: Find direct links to the best-rated dark themes. at the bottom
Short description: Add a system-wide dark theme option for Windows 8.1 that applies darker colors to UI chrome, system apps, File Explorer, and common controls to reduce eye strain and improve battery life on compatible displays. Popular options include: A minimalist, neutral dark grey
These do darken File Explorer or system dialogs.