Theming

How DropTerm picks its theme mode and color scheme - the Application theme dropdown and the two per-mode scheme picks.

Application theme

Which theme mode is active - and with it which of the two color schemes wears, the window background derivation, and all chrome - comes from the “Application theme” dropdown in the Appearance section of the settings drawer, so you don’t need COSMIC Appearance to flip the terminal’s mode:

• Follow system (the default): DropTerm tracks the system light/dark mode. Flipping COSMIC Appearance switches the terminal’s scheme, background, chrome, and the settings drawer itself, exactly as before - a config that never touches this key behaves byte-identically to a build without the dropdown.
• Dark / Light: the app pins that mode independently of the system. Everything resolves from the pin - scheme selection, window background, tab/grab-bar chrome, and the settings drawer - built on your own system palettes (accent included), and the pin survives system theme flips: COSMIC Appearance can flip back and forth while the terminal keeps wearing the pinned mode. One upstream edge: while pinned, palette edits made while the system sits in the opposite mode are dropped until the next re-pin or theme change.
• Switching back to Follow system re-derives the current system mode on the spot, and system flips resume driving the app.

Picks apply live (config key theme_preference: System, Dark, or Light - a missing key loads as System). With the settings drawer open the terminal is right there beneath it, so a theme pick is visible immediately - the terminal’s cells, background, and chrome restyle in the same pass, and the drawer restyles along with them.

Color schemes

The terminal wears a built-in color scheme picked per theme mode: the Appearance card of the settings drawer has two scheme pickers - “Dark color scheme” (worn while the app resolves dark mode) and “Light color scheme” (while it resolves light). The palette is the preview: the closed control shows the configured scheme’s name over a strip of its actual colors, and opening it lists every scheme as its name plus swatches - the background, the foreground, then the sixteen ANSI colors the terminal renders with. Those eighteen colors are literally everything a scheme ever shows, so there is no name-as-proxy and no separate preview pane; the chips resolve through the same conversion the terminal renders with, so a chip can never disagree with the live scheme. The COSMIC pair ships no background (the window follows the system theme), so its background chip previews exactly that - the surface color itself. A row pick applies live, Escape or a click away closes without picking, and the picked row is marked. The active mode comes from the Application theme dropdown - Follow system tracks COSMIC Appearance, Dark/Light pin one - and a mode change from either side switches between the two picks; a config edit or a mode change re-applies live.

Twelve built-in schemes ship: COSMIC Dark and COSMIC Light (the defaults), Dracula, Solarized Dark, Solarized Light, Gruvbox Dark, Gruvbox Light, Tokyo Night Storm, Tokyo Night Day, Nord, Catppuccin Mocha, and Catppuccin Latte - values transcribed from their canonical upstream palettes, with the source and license recorded per scheme in src/terminal/theme_source.rs.

• Every scheme except the COSMIC pair owns its background: picking Dracula renders Dracula’s #282a36 behind the cells, and the chrome - tab bar, grab bar - follows the scheme background, so cells and chrome cannot disagree. The COSMIC pair keeps following the system theme’s background, as always. opacity multiplies on top of either background.
• A scheme’s name is the config format: a pick persists the display name under color_scheme_dark/color_scheme_light. A name not in the registry (stale, hand-typed, or renamed upstream) silently falls back to the COSMIC pair for that mode - no error, no migration - and the picker marks no row until you pick again (the closed control still shows the stored name, honest about what the file says).
• Dim variants are derived, not shipped: each normal color’s channels are scaled by 0.66 (Alacritty’s dim rule), one uniform rule for every non-COSMIC scheme. Bright variants come from the palettes themselves.
• User-defined scheme files are not supported; the built-in registry is the whole feature (see the ROADMAP’s “Later” section).