Introduce central theme module; rounded borders and consistent styling

All colors/styles for windows, panel, dropdown and desktop now live in
src/theme.rs — restyle the whole WM from one file. Windows and menus
use rounded borders; hover/focus states share one accent style.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/main.rs

@@ -7,6 +7,7 @@ mod log;
 mod pty;
 mod render;
 mod server;
+mod theme;
 
 use app::{App, AppIpcOut, WindowContent};
 use config::Config;

src/render.rs

@@ -1,10 +1,11 @@
 use crate::app::{App, DropdownState, FloatingWindow, ResizeEdge, WindowContent};
+use crate::theme;
 use crate::config::StatusAlign;
 use ratatui::{
     layout::Rect,
     style::{Color, Modifier, Style},
     text::{Line, Span},
-    widgets::{Block, Borders, Clear, Paragraph, Wrap},
+    widgets::{Block, BorderType, Borders, Clear, Paragraph, Wrap},
     Frame,
 };
 
@@ -15,7 +16,7 @@ pub fn render(frame: &mut Frame, app: &App) {
     let bg_color = if app.config.background_image.is_some() {
         Color::Reset
     } else {
-        Color::Indexed(235)
+        theme::DESKTOP_BG
     };
     frame.render_widget(
         Block::default().style(Style::default().bg(bg_color)),
@@ -76,15 +77,15 @@ fn render_panel(
 ) {
     // Panelens bakgrund
     frame.render_widget(
-        Block::default().style(Style::default().bg(Color::Indexed(238))),
+        Block::default().style(Style::default().bg(theme::PANEL_BG)),
         rect,
     );
 
     // Logotyp – klickbar meny-knapp med hover-highlight
     let logo_style = if hovered_tui {
-        Style::default().fg(Color::Black).bg(Color::Cyan).add_modifier(Modifier::BOLD)
+        theme::hover_highlight()
     } else {
-        Style::default().fg(Color::Cyan).add_modifier(Modifier::BOLD)
+        theme::logo()
     };
     frame.render_widget(
         Paragraph::new(Span::styled(" TUI-WM ", logo_style)),
@@ -92,9 +93,9 @@ fn render_panel(
     );
 
     // Fokus-indikator: grön ● = skrivbord fokuserat, grå ● = fönster fokuserat
-    let dot_color = if desktop_focused { Color::Green } else { Color::Indexed(240) };
+    let dot_color = if desktop_focused { theme::OK } else { theme::HINT };
     frame.render_widget(
-        Paragraph::new(Span::styled("●", Style::default().fg(dot_color).bg(Color::Indexed(238)))),
+        Paragraph::new(Span::styled("●", Style::default().fg(dot_color).bg(theme::PANEL_BG))),
         Rect::new(rect.x + 10, rect.y, 1, 1),
     );
 
@@ -103,9 +104,9 @@ fn render_panel(
         let Some(&ir) = item_rects.get(ii) else { continue };
         let is_hovered = hovered == Some((panel_idx, ii));
         let style = if is_hovered {
-            Style::default().fg(Color::Black).bg(Color::Cyan).add_modifier(Modifier::BOLD)
+            theme::hover_highlight()
         } else {
-            Style::default().fg(Color::White).bg(Color::Indexed(238))
+            Style::default().fg(theme::TEXT).bg(theme::PANEL_BG)
         };
         frame.render_widget(
             Paragraph::new(Span::styled(format!(" {} ", item.label), style)),
@@ -131,7 +132,7 @@ fn render_panel(
         frame.render_widget(
             Paragraph::new(Span::styled(
                 padded,
-                Style::default().fg(Color::Indexed(252)).bg(Color::Indexed(238)),
+                theme::panel_item(),
             )),
             draw_rect,
         );
@@ -150,7 +151,7 @@ fn render_panel(
         frame.render_widget(
             Paragraph::new(Span::styled(
                 padded,
-                Style::default().fg(Color::Indexed(252)).bg(Color::Indexed(238)),
+                theme::panel_item(),
             )),
             draw_rect,
         );
@@ -164,16 +165,17 @@ fn render_dropdown(frame: &mut Frame, dd: &DropdownState) {
     frame.render_widget(
         Block::default()
             .borders(Borders::ALL)
-            .border_style(Style::default().fg(Color::Cyan))
+            .border_type(BorderType::Rounded)
-            .style(Style::default().bg(Color::Indexed(236))),
+            .border_style(Style::default().fg(theme::ACCENT))
+            .style(Style::default().bg(theme::MENU_BG)),
         border_rect,
     );
     for (i, (item, &ir)) in dd.items.iter().zip(dd.item_rects.iter()).enumerate() {
         let is_hovered = dd.hovered == Some(i);
         let style = if is_hovered {
-            Style::default().fg(Color::Black).bg(Color::Cyan).add_modifier(Modifier::BOLD)
+            theme::hover_highlight()
         } else {
-            Style::default().fg(Color::White).bg(Color::Indexed(236))
+            Style::default().fg(theme::TEXT).bg(theme::MENU_BG)
         };
         // ir pekar redan på den faktiska raden innanför kanten
         let draw_rect = Rect::new(ir.x + 1, ir.y, ir.width.saturating_sub(2), 1);
@@ -200,15 +202,7 @@ fn render_window(
     let is_focused = focused_id == Some(window.id);
     let is_resizing = window.resizing.is_some();
 
-    let border_style = if is_resizing {
+    let border_style = theme::window_border(is_focused, is_resizing, resize_hover.is_some());
-        Style::default().fg(Color::Yellow)
-    } else if resize_hover.is_some() {
-        Style::default().fg(Color::Indexed(220)) // ljusgul vid hover på kant
-    } else if is_focused {
-        Style::default().fg(Color::Cyan)
-    } else {
-        Style::default().fg(Color::Indexed(242))
-    };
 
     let title_text = match &window.content {
         WindowContent::Terminal { title, .. } => format!(" {} ", title),
@@ -219,11 +213,9 @@ fn render_window(
     frame.render_widget(Clear, full_rect);
     frame.render_widget(
         Block::default()
-            .title(Span::styled(
+            .title(Span::styled(&title_text, theme::window_title()))
-                &title_text,
-                Style::default().fg(Color::White).add_modifier(Modifier::BOLD),
-            ))
             .borders(Borders::ALL)
+            .border_type(BorderType::Rounded)
             .border_style(border_style)
             .style(Style::default().bg(match &window.content {
                 WindowContent::Terminal { .. } => terminal_bg,
@@ -237,9 +229,9 @@ fn render_window(
     if cb.x + 3 <= full_rect.x + full_rect.width {
         let close_hov = hovered_close == Some(window.id);
         let close_style = if close_hov {
-            Style::default().fg(Color::White).bg(Color::Red).add_modifier(Modifier::BOLD)
+            Style::default().fg(theme::TEXT).bg(theme::DANGER).add_modifier(Modifier::BOLD)
         } else {
-            Style::default().fg(Color::Red)
+            Style::default().fg(theme::DANGER)
         };
         frame.render_widget(Paragraph::new(Span::styled("[X]", close_style)), cb);
     }
@@ -326,9 +318,9 @@ fn render_popup_dialog(
     for (i, label) in labels.iter().enumerate() {
         let w = label.len() as u16;
         let style = if i == *selected {
-            Style::default().fg(Color::Black).bg(Color::Cyan).add_modifier(Modifier::BOLD)
+            theme::hover_highlight()
         } else {
-            Style::default().fg(Color::White).bg(Color::Indexed(238))
+            Style::default().fg(theme::TEXT).bg(theme::PANEL_BG)
         };
         if btn_x + w <= rect.x + rect.width {
             frame.render_widget(

src/theme.rs

@@ -0,0 +1,70 @@
+//! Centralt tema för TUI-WM.
+//!
+//! ALLA färger och återkommande stilar definieras här — ändra utseendet
+//! på hela fönsterhanteraren från en enda fil. render.rs ska inte
+//! hårdkoda `Color::`-literaler för sådant som temat täcker.
+
+use ratatui::style::{Color, Modifier, Style};
+
+// ─── Palett ──────────────────────────────────────────────────────────────
+/// Fokusmarkering (fönsterram, logga, markerade menyrader)
+pub const ACCENT: Color = Color::Cyan;
+/// Pågående storleksändring
+pub const RESIZE: Color = Color::Yellow;
+/// Hover över fönsterkant (inför resize)
+pub const RESIZE_HOVER: Color = Color::Indexed(220);
+/// Ofokuserad fönsterram
+pub const BORDER_DIM: Color = Color::Indexed(242);
+/// Skrivbordsbakgrund (när ingen bakgrundsbild används)
+pub const DESKTOP_BG: Color = Color::Indexed(235);
+/// Panelens bakgrund
+pub const PANEL_BG: Color = Color::Indexed(238);
+/// Dropdown-menyns bakgrund
+pub const MENU_BG: Color = Color::Indexed(236);
+/// Normal text
+pub const TEXT: Color = Color::White;
+/// Panel-text (något nedtonad)
+pub const PANEL_TEXT: Color = Color::Indexed(252);
+/// Hints och inaktiva indikatorer
+pub const HINT: Color = Color::Indexed(240);
+/// Positiv indikator (skrivbordsfokus-punkten)
+pub const OK: Color = Color::Green;
+/// Destruktivt (stäng-knappen)
+pub const DANGER: Color = Color::Red;
+
+// ─── Stilar ──────────────────────────────────────────────────────────────
+/// Ramstil för ett fönster utifrån dess tillstånd.
+pub fn window_border(focused: bool, resizing: bool, resize_hover: bool) -> Style {
+    if resizing {
+        Style::default().fg(RESIZE)
+    } else if resize_hover {
+        Style::default().fg(RESIZE_HOVER)
+    } else if focused {
+        Style::default().fg(ACCENT)
+    } else {
+        Style::default().fg(BORDER_DIM)
+    }
+}
+
+/// Markerad rad/knapp (hover): inverterad accent.
+pub fn hover_highlight() -> Style {
+    Style::default()
+        .fg(Color::Black)
+        .bg(ACCENT)
+        .add_modifier(Modifier::BOLD)
+}
+
+/// TUI-WM-loggan i panelen.
+pub fn logo() -> Style {
+    Style::default().fg(ACCENT).add_modifier(Modifier::BOLD)
+}
+
+/// Panel-objekt (menyknappar) i normalläge.
+pub fn panel_item() -> Style {
+    Style::default().fg(PANEL_TEXT).bg(PANEL_BG)
+}
+
+/// Fönstertitel.
+pub fn window_title() -> Style {
+    Style::default().fg(TEXT).add_modifier(Modifier::BOLD)
+}