feat(theme): add Gaia Aether palette

CHANGELOG.md

@@ -5,6 +5,31 @@ All notable changes to `markdown-tui-explorer` are documented here.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Added — Gaia Aether theme
+
+A ninth built-in palette: Gruvbox warmth (cream `#f2e5bc` text, moss and
+amber hues) on a blue-grey `#181c22` surface, with a dusty-mauve accent.
+Select it in the settings modal under **Theme** or with
+`theme = "gaia_aether"` in `config.toml`.
+
+Three slots deliberately depart from the source palette, because its literal
+values fail the contrast audit in `src/theme/mod.rs::tests`:
+
+- `accent.primary` uses the source magenta `#c98fa0` rather than the source
+  accent `#a0607a`. No foreground colour reaches WCAG AA (4.5:1) on
+  `#a0607a` — its ceiling is 3.76:1 — so it cannot carry the `on_accent`
+  text drawn by the status bar and tab bar. `#a0607a` remains available as
+  `accent.alt`.
+- `state.selection_bg` is a lightened `#503a4a`. The source selection
+  `#261a28` sits 0.16 luminance units from the background surface, below the
+  `MIN_SELECTION_DELTA` of 3.0, so a selection highlight would be invisible.
+- `state.focus` is the magenta accent, 6.45:1 against the base surface.
+
+The existing audit tests cover the new variant automatically, so the palette
+is pinned to the same AA floor as every other theme.
+
 ## [1.35.1] — 2026-08-31
 
 ### Fixed — Mermaid quoted and delimiter-containing labels (#40)

README.md

@@ -76,7 +76,7 @@ a 500-file cap with a truncation footer.
 
 ![Global search modal](https://raw.githubusercontent.com/leboiko/markdown-reader/master/docs/screenshots/global-search.png)
 
-Eight themes ship built-in, including light variants. Settings modal
+Nine themes ship built-in, including light variants. Settings modal
 reached via `c`.
 
 ![GitHub Light theme with settings open](https://raw.githubusercontent.com/leboiko/markdown-reader/master/docs/screenshots/settings-github-light.png)
@@ -166,8 +166,9 @@ drawn on the left of the viewer content when enabled.
   The modal supports column-boundary panning (`h`/`l` snap to the next
   column, `H`/`L` half-page pan), mouse scroll wheel (plain for rows,
   `Shift`+wheel for columns), and click-outside-to-close.
-- **Themes** — eight built-in palettes (Default, Dracula, Solarized Dark,
-  Solarized Light, Nord, Gruvbox Dark, Gruvbox Light, GitHub Light).
+- **Themes** — nine built-in palettes (Default, Dracula, Solarized Dark,
+  Solarized Light, Nord, Gruvbox Dark, Gruvbox Light, GitHub Light,
+  Gaia Aether).
   Switch live from the settings modal; every open document re-renders
   with the new colors.
 - **Session resume** — per-project: the last open tabs, active tab, and
@@ -710,7 +711,7 @@ it past the viewport and press `Enter` again for the next.
 
 ## Themes
 
-Eight built-in themes (five dark, three light), switchable live from
+Nine built-in themes (six dark, three light), switchable live from
 the settings modal (`c`):
 
 - **Default** — balanced palette that works on dark terminals.
@@ -721,6 +722,8 @@ the settings modal (`c`):
 - **Gruvbox Dark** — warm retro groove.
 - **Gruvbox Light** — warm retro light variant.
 - **GitHub Light** — bright palette for light terminals.
+- **Gaia Aether** — Gruvbox warmth (cream text, moss and amber hues) on a
+  blue-grey surface, with a dusty-mauve accent.
 
 Theme changes re-render every open tab immediately, so switching feels
 instantaneous. The choice is persisted and restored on next launch.
@@ -740,7 +743,7 @@ app starts with defaults rather than refusing to launch.
 Fields:
 
 ```toml
-theme = "dracula"          # default | dracula | solarized_dark | solarized_light | nord | gruvbox_dark | gruvbox_light | github_light
+theme = "dracula"          # default | dracula | solarized_dark | solarized_light | nord | gruvbox_dark | gruvbox_light | github_light | gaia_aether
 show_line_numbers = true
 show_file_tree = true      # true | false; false starts hidden (H still toggles)
 tree_position = "left"     # left | right

src/theme/mod.rs

@@ -50,6 +50,7 @@ pub enum Theme {
     GruvboxDark,
     GruvboxLight,
     GithubLight,
+    GaiaAether,
 }
 
 impl Theme {
@@ -63,6 +64,7 @@ impl Theme {
         Theme::GruvboxDark,
         Theme::GruvboxLight,
         Theme::GithubLight,
+        Theme::GaiaAether,
     ];
 
     /// Human-readable display name for the theme.
@@ -76,6 +78,7 @@ impl Theme {
             Theme::GruvboxDark => "Gruvbox Dark",
             Theme::GruvboxLight => "Gruvbox Light",
             Theme::GithubLight => "GitHub Light",
+            Theme::GaiaAether => "Gaia Aether",
         }
     }
 
@@ -95,6 +98,7 @@ impl Theme {
             Theme::Default | Theme::SolarizedDark | Theme::Nord => "base16-ocean.dark",
             Theme::Dracula | Theme::GruvboxDark => "base16-eighties.dark",
             Theme::SolarizedLight | Theme::GruvboxLight | Theme::GithubLight => "InspiredGitHub",
+            Theme::GaiaAether => "base16-eighties.dark",
         }
     }
 }

src/theme/themes.rs

@@ -635,3 +635,102 @@ pub(super) fn github_light() -> Tokens {
         },
     }
 }
+
+/// Gaia Aether — the dark Gruvbox/terracotta palette used across the author's
+/// desktop theme ("AETHER / G.A.I.A v2": Gruvbox, terracotta, and dusty mauve).
+///
+/// Slots carry the source-palette names from that theme's `colors.toml`:
+/// `background` `#181c22`, `lighter_background` `#1e2228`, `foreground`
+/// `#f2e5bc`, `dark_foreground` `#8a7e70`, `accent` `#a0607a`, `selection`
+/// `#261a28`, plus the Gruvbox-derived hue slots.
+///
+/// Three slots deviate from the source palette because its literal values
+/// fail this crate's own contrast audit:
+///
+/// * `accent.primary` is the theme's dusty-mauve/tan `magenta` `#c98fa0`
+///   rather than `accent` `#a0607a`. No foreground reaches WCAG AA (4.5:1)
+///   on `#a0607a` — its ceiling is 3.76:1 — so it cannot carry the
+///   `on_accent` text drawn by the status bar and tab bar. `#a0607a` stays
+///   in the palette as `accent.alt`.
+/// * `state.selection_bg` `#503a4a` is a lightened `selection` — the
+///   source `#261a28` sits only 0.16 luminance units from `background`,
+///   below the `MIN_SELECTION_DELTA` of 3.0, and would render invisible.
+/// * `state.focus` is the magenta accent, 6.45:1 on `background`.
+pub(super) fn gaia_aether() -> Tokens {
+    // AETHER / G.A.I.A v2 base surfaces and reading text.
+    let bg = Color::Rgb(24, 28, 34); // background        #181c22
+    let raised = Color::Rgb(30, 34, 40); // lighter_background #1e2228
+    let brown = Color::Rgb(60, 56, 54); // brown             #3c3836
+    let fg = Color::Rgb(242, 229, 188); // foreground        #f2e5bc
+    let gray = Color::Rgb(168, 153, 132); // gruvbox fg4       #a89984
+    let dark_fg = Color::Rgb(138, 126, 112); // dark_foreground   #8a7e70
+    // Hue slots, Gruvbox-derived in the source theme.
+    let orange = Color::Rgb(208, 128, 80); // orange            #d08050
+    let yellow = Color::Rgb(184, 151, 90); // yellow            #b8975a
+    let bright_yellow = Color::Rgb(212, 176, 122); // bright_yellow     #d4b07a
+    let green = Color::Rgb(122, 158, 126); // green             #7a9e7e
+    let cyan = Color::Rgb(131, 165, 152); // cyan              #83a598
+    let mauve = Color::Rgb(201, 143, 160); // magenta           #c98fa0
+    let deep_mauve = Color::Rgb(160, 96, 122); // accent            #a0607a
+    let selection = Color::Rgb(80, 58, 74); // selection, lightened #261a28
+    Tokens {
+        surface: Surface {
+            base: bg,
+            raised,
+            border: brown,
+        },
+        text: Text {
+            primary: fg,
+            muted: gray,
+            // Dark base on the bright mauve accent: 6.45:1.
+            on_accent: bg,
+            title: fg,
+        },
+        state: State {
+            selection_bg: selection,
+            selection_fg: fg,
+            focus: mauve,
+            search_bg: bright_yellow,
+            current_match_bg: orange,
+            // Dark base reads 8.38:1 on bright_yellow and 5.61:1 on orange.
+            match_fg: bg,
+        },
+        accent: Accent {
+            primary: mauve,
+            alt: deep_mauve,
+            link: cyan,
+        },
+        syntax: Syntax {
+            inline_code: green,
+            code_fg: fg,
+            code_border: brown,
+        },
+        heading: Heading {
+            h1: green,
+            h2: cyan,
+            h3: mauve,
+            other: fg,
+        },
+        status: Status {
+            // Darker than `raised`: the source theme's `dark_background`.
+            bg: Color::Rgb(22, 26, 31), // #161a1f
+            fg: gray,
+            help_bg: bg,
+            gutter: dark_fg,
+        },
+        list: List {
+            marker: bright_yellow,
+            task_marker: green,
+            block_quote_fg: gray,
+            block_quote_border: dark_fg,
+        },
+        table: Table {
+            header: cyan,
+            border: brown,
+        },
+        git: Git {
+            new: green,
+            modified: yellow,
+        },
+    }
+}

src/theme/tokens.rs

@@ -140,6 +140,7 @@ impl Tokens {
             Theme::GruvboxDark => super::themes::gruvbox_dark(),
             Theme::GruvboxLight => super::themes::gruvbox_light(),
             Theme::GithubLight => super::themes::github_light(),
+            Theme::GaiaAether => super::themes::gaia_aether(),
         }
     }
 }