Appearance
Light, dark or system; the nine base colours, from Neutral to Argilla and Grafite; translucency; the interface, code and terminal faces.
Settings → Appearance controls how Sirio looks. Its Theme section holds three rows: Appearance, Base color and Translucency.
Light and dark
The Appearance row offers System, Light or Dark. System follows your desktop’s own setting. On Linux, Sirio asks the desktop portal for it and stays dark until the portal answers, or when no portal runs.
The palette starts from bezel, the UI library behind Sirio’s interface. Sirio pulls body text back a little from full contrast to reduce glare, and it still clears WCAG AA contrast on the panels, in light mode as well as dark.
Base colour
The Base color row picks the greys Sirio paints the whole window in, from nine: Neutral, Stone, Zinc, Gray, Slate, Notte, Onice, Argilla and Grafite. Neutral is the default.
Stone, Zinc, Gray and Slate carry a hue. They tint bezel’s greys and move only the hue, so lightness stays where bezel set it and every one keeps the contrast Sirio verified in the shipped palette.
Neutral, Notte, Onice, Argilla and Grafite paint surfaces of their own, so they move lightness too:
- Neutral has no hue and paints its own ladder of greys in both modes. In dark mode the central panes and the terminal sit at #0E0E0E, a step below the sidebars and panels at #131313, with the chat and dialogs lighter at #1A1A1A, the composer lighter at #242424 and the hover at #292929.
- Notte carries a cool hue, and in dark mode it paints four surfaces of its own: #0E1016 at the back, #202127 for the sidebars, the panels and the terminal, #2B2F3A for raised cards and dialogs, and #313337 for a raised element under the pointer. In light mode Notte is its hue alone.
- Onice has no hue, and in dark mode its greys start at pure black: the terminal and the central panes at #000000, sidebars and panels at #0A0A0A, the chat and dialogs at #141414. Depth comes from those steps alone, since a shadow cannot be darker than black. In light mode Onice looks the same as Neutral. An older Sirio does not know Onice and falls back to Neutral.
- Argilla and Grafite carry a warm hue and paint solid ladders of greys of their own, which follow the two palettes of Claude’s desktop app.
The terminal follows the base colour. In dark mode it takes the central panes’ grey under Neutral and Onice, and the sidebar’s surface under Stone, Zinc, Gray, Slate and Notte. Under Argilla and Grafite it sits one step darker than the panes. In light mode it stays paper white under Stone, Zinc, Gray, Slate and Notte, and it takes the page’s grey under Neutral and Onice. The borders and the status colours stay the same under every base.
Translucency
The Translucency switch lets a blurred view of your desktop show through the window, on macOS and Windows. On Linux the window stays opaque. It starts off.
Font sizes
You set the interface font size and the terminal font size separately, under Interface and Terminal, each from 12 to 18 points. The interface size also scales the worktree names in the sidebar and the rest of the sidebar chrome.
The faces
Geist is the interface face and Geist Mono the code face. bezel registers both before the first window opens, so every platform has them, whatever fonts the machine carries.
The terminal is the exception. It ships its own face, the Nerd Fonts build of JetBrains Mono, in regular, bold, italic and bold italic. Agent CLIs draw their status lines with Powerline and icon glyphs, and a machine without a Nerd Font installed used to render those as empty boxes. macOS prefers Apple’s SF Mono and falls back to the bundled face. Everywhere else the bundled face leads, so you no longer need a Nerd Font of your own, and one you have installed does no harm.