Add MIT license and configurable greeter palette

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Wiktor A. Falkowski
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -33,9 +33,21 @@ Cage and a greeter account must be installed/configured separately. Gentoo's com
 
 The session picker is hidden by default; press **F2** to show or hide it. The login surface starts with only the username and login button; PAM prompts reveal the response field when needed. The picker reads `*.desktop` entries from `/usr/share/wayland-sessions` and `/usr/local/share/wayland-sessions`. If neither has entries, it offers a `Hyprland` fallback command. The selected entry's `Exec` is parsed into argv and passed to greetd directly, without shell expansion.
 
+## Colors
+
+At startup the greeter reads `~/.config/wayter/colors.ini`. The tracked [`colors.ini.example`](colors.ini.example) contains the current dark steel-blue palette; copy it into place with:
+
+```sh
+mkdir -p ~/.config/wayter
+cp colors.ini.example ~/.config/wayter/colors.ini
+```
+
+Edit values in the `[colors]` section using six-digit hex colors such as `accent = #6C99BB`. Supported names are `background`, `panel`, `surface`, `hover`, `border`, `focus`, `text`, `muted`, `dim`, `emphasis`, `accent`, `accent_secondary`, and `warning`. Invalid values keep that color's built-in default, and a missing or unreadable file falls back to the full built-in palette.
+
 ## Design notes
 
 - PAM prompts come from greetd IPC and are not assumed to be a single username/password exchange.
 - Secrets are never written to disk or logged.
-- The card is centered by GTK's center container in both dimensions. Its UI colors come only from `~/.config/foot/foot.ini`; it uses Maple Mono and GTK4 system libraries.
-- See the project skill `hyprland-greetd-greeter` for protocol, host, and maintenance guidance.
+- The card is centered by GTK's center container in both dimensions. GTK CSS colors come from `~/.config/wayter/colors.ini`; it uses Maple Mono and GTK4 system libraries.
+
+The project is available under the [MIT License](LICENSE).

colors.ini.example

@@ -0,0 +1,14 @@
+[colors]
+background = #151515
+panel = #181818
+surface = #202020
+hover = #282828
+border = #2F2F2F
+focus = #454545
+text = #D0D0D0
+muted = #757575
+dim = #505050
+emphasis = #F5F5F5
+accent = #6C99BB
+accent_secondary = #547C99
+warning = #D3A04D

src/main.rs

@@ -4,7 +4,7 @@ use serde::{Deserialize, Serialize};
 use std::fs;
 use std::io::{Read, Write};
 use std::os::unix::net::UnixStream;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::sync::mpsc::{self, Receiver, Sender};
 use std::thread;
 use std::time::Duration;
@@ -87,6 +87,121 @@ struct Session {
     command: Vec<String>,
 }
 
+#[derive(Clone)]
+struct Palette {
+    background: String,
+    panel: String,
+    surface: String,
+    hover: String,
+    border: String,
+    focus: String,
+    text: String,
+    muted: String,
+    dim: String,
+    emphasis: String,
+    accent: String,
+    accent_secondary: String,
+    warning: String,
+}
+
+impl Default for Palette {
+    fn default() -> Self {
+        Self {
+            background: "#151515".into(),
+            panel: "#181818".into(),
+            surface: "#202020".into(),
+            hover: "#282828".into(),
+            border: "#2F2F2F".into(),
+            focus: "#454545".into(),
+            text: "#D0D0D0".into(),
+            muted: "#757575".into(),
+            dim: "#505050".into(),
+            emphasis: "#F5F5F5".into(),
+            accent: "#6C99BB".into(),
+            accent_secondary: "#547C99".into(),
+            warning: "#D3A04D".into(),
+        }
+    }
+}
+
+impl Palette {
+    fn load() -> Self {
+        let Some(home) = std::env::var_os("HOME").map(PathBuf::from) else {
+            eprintln!("HOME is unset; using the built-in greeter palette");
+            return Self::default();
+        };
+        let path = home.join(".config/wayter/colors.ini");
+        match fs::read_to_string(&path) {
+            Ok(contents) => Self::parse(&contents, &path),
+            Err(error) => {
+                eprintln!(
+                    "Could not read {}: {error}; using the built-in palette",
+                    path.display()
+                );
+                Self::default()
+            }
+        }
+    }
+
+    fn parse(contents: &str, path: &Path) -> Self {
+        let mut palette = Self::default();
+        let mut in_colors = false;
+        for (index, raw_line) in contents.lines().enumerate() {
+            let line = raw_line.trim();
+            if line.is_empty() || line.starts_with('#') || line.starts_with(';') {
+                continue;
+            }
+            if line.starts_with('[') && line.ends_with(']') {
+                in_colors = line == "[colors]";
+                continue;
+            }
+            if !in_colors {
+                continue;
+            }
+            let Some((key, value)) = line.split_once('=') else {
+                eprintln!("{}:{}: expected key = #RRGGBB", path.display(), index + 1);
+                continue;
+            };
+            let key = key.trim();
+            let value = value.trim();
+            let Some(color) = Self::valid_color(value) else {
+                eprintln!(
+                    "{}:{}: invalid color for {key}; keeping its default",
+                    path.display(),
+                    index + 1
+                );
+                continue;
+            };
+            let target = match key {
+                "background" => &mut palette.background,
+                "panel" => &mut palette.panel,
+                "surface" => &mut palette.surface,
+                "hover" => &mut palette.hover,
+                "border" => &mut palette.border,
+                "focus" => &mut palette.focus,
+                "text" => &mut palette.text,
+                "muted" => &mut palette.muted,
+                "dim" => &mut palette.dim,
+                "emphasis" => &mut palette.emphasis,
+                "accent" => &mut palette.accent,
+                "accent_secondary" => &mut palette.accent_secondary,
+                "warning" => &mut palette.warning,
+                _ => continue,
+            };
+            *target = color;
+        }
+        palette
+    }
+
+    fn valid_color(value: &str) -> Option<String> {
+        let hex = value.strip_prefix('#')?;
+        if hex.len() != 6 || !hex.bytes().all(|byte| byte.is_ascii_hexdigit()) {
+            return None;
+        }
+        Some(format!("#{}", hex.to_ascii_uppercase()))
+    }
+}
+
 fn main() {
     let app = gtk::Application::builder()
         .application_id("dev.wfalkowski.WaylandGreeter")
@@ -536,21 +651,39 @@ fn split_exec(input: &str) -> Vec<String> {
 }
 
 fn install_style() {
-    let css = r#"
-        .backdrop { background: #151515; color: #d0d0d0; font-family: "Maple Mono Normal"; font-size: 9pt; }
-        .card { background: #151515; border: 1px solid #505050; border-radius: 1px; padding: 18px; }
-        .field-label { color: #505050; font-size: 9pt; }
-        entry, combobox button { color: #d0d0d0; background: #151515; border: 1px solid #505050; border-radius: 1px; min-height: 36px; padding: 0 10px; caret-color: #f5f5f5; }
-        entry:focus, combobox button:focus { border-color: #6c99bb; }
-        entry placeholder { color: #505050; }
-        button.login-button { color: #d0d0d0; background: #151515; border: 1px solid #505050; border-radius: 1px; min-height: 36px; margin-top: 2px; }
-        button.login-button:hover { color: #f5f5f5; background: #547c99; }
-        button.login-button:focus { border-color: #6c99bb; }
-        button.login-button:disabled { color: #505050; background: #151515; border-color: #505050; }
-        .status { color: #d3a04d; font-size: 9pt; }
-    "#;
+    let palette = Palette::load();
+    let css = format!(
+        r#"
+        .backdrop {{ background: {background}; color: {text}; font-family: "Maple Mono Normal"; font-size: 9pt; }}
+        .card {{ background: {panel}; border: 1px solid {border}; border-radius: 1px; padding: 18px; }}
+        .field-label {{ color: {muted}; font-size: 9pt; }}
+        entry, combobox button {{ color: {text}; background: {surface}; border: 1px solid {border}; border-radius: 1px; min-height: 36px; padding: 0 10px; caret-color: {emphasis}; }}
+        entry:focus, combobox button:focus {{ border-color: {accent}; }}
+        entry placeholder {{ color: {dim}; }}
+        button.login-button {{ color: {text}; background: {surface}; border: 1px solid {border}; border-radius: 1px; min-height: 36px; margin-top: 2px; }}
+        button.login-button:hover {{ color: {emphasis}; background: {accent_secondary}; }}
+        button.login-button:focus {{ border-color: {focus}; }}
+        button.login-button:disabled {{ color: {dim}; background: {panel}; border-color: {border}; }}
+        .status {{ color: {warning}; font-size: 9pt; }}
+        .field-label:disabled {{ color: {dim}; }}
+        entry:selected, combobox button:selected {{ background: {hover}; }}
+    "#,
+        background = palette.background,
+        panel = palette.panel,
+        surface = palette.surface,
+        hover = palette.hover,
+        border = palette.border,
+        focus = palette.focus,
+        text = palette.text,
+        muted = palette.muted,
+        dim = palette.dim,
+        emphasis = palette.emphasis,
+        accent = palette.accent,
+        accent_secondary = palette.accent_secondary,
+        warning = palette.warning,
+    );
     let provider = gtk::CssProvider::new();
-    provider.load_from_data(css);
+    provider.load_from_data(&css);
     if let Some(display) = gtk::gdk::Display::default() {
         gtk::style_context_add_provider_for_display(
             &display,