Ripcord now supports loading a custom theme from a json file (eventually it will be in the GUI).

Create a file custom_theme.json alongside your settings.ini file, and put this text into it:

{
    "alternate_base": "#29292b",
    "base": "#2e2f31",
    "bright_text": "#ffffff",
    "button": "#3d3e43",
    "chat_timestamp": "#494b4e",
    "disabled_button": "#393a3e",
    "disabled_icon": "#a4a6a8",
    "disabled_text": "#a4a6a8",
    "highlight": "#bfc7d5",
    "highlighted_text": "#2d2c27",
    "icon": "#d0d1d4",
    "shadow": "#2e2f31",
    "text": "#d0d1d4",
    "unread_badge": "#d0d1d4",
    "unread_badge_text": "#2d2c27",
    "window": "#3c3d40"
}

These are the same colors as the default Carbon theme. When Ripcord starts up, if the file is detected and parsed correctly, it will be used instead of whatever theme you've chosen in the preferences GUI. If you make any changes to the custom_theme.json file, you'll need to restart Ripcord to see those changes.