Theming and custom skins

[syedazeez337]

Summary

Add built-in color themes and user-customizable skins via config.toml.

Motivation

k9s has extensive theming. Users want their tools to match their terminal aesthetic. This is a low-effort, high-satisfaction feature.

Requirements

Built-in Themes

• dark (default — current colors)
• light — optimized for light terminal backgrounds
• dracula — popular dark theme
• nord — muted Nordic palette
• solarized — Solarized dark/light

Config

[theme]
name = "dark"                     # built-in theme name
# OR custom overrides:
# status_healthy = "green"
# status_warning = "yellow"
# status_critical = "red"
# kind_pod = "green"
# kind_service = "blue"
# kind_deployment = "yellow"
# header_fg = "white"
# header_bg = "black"
# selected_bg = "blue"

Implementation

• Create src/theme.rs module
• Define Theme struct with all color fields
• Built-in themes as const/static instances
• Custom overrides merge on top of base theme
• Thread theme through to items.rs display functions and main.rs header

Color Format

• Named colors: red, green, blue, yellow, cyan, magenta, white, black, gray
• 256-color: color(123)
• RGB: #ff5733
• Map to ratatui::style::Color

Acceptance Criteria

• 5 built-in themes selectable via config
• Custom color overrides work
• Theme applied to all UI elements (list, header, preview, status)
• Colors render correctly on dark and light terminals
• Tests: theme loading and color mapping