feat: configurable terminal cell width mode

新增全局「字体间距」偏好：紧凑（上游兼容默认）或宽松。

终端把字体的非整数平均 advance 转成整像素列宽时，上游一律向下取整。同样的
字体与字号下，向下取整会少一像素。宽松改用最接近整数取整补上
这一像素，紧凑保持现有取整，因此现有列数与换行行为不变。

该偏好只控制终端内容网格的列宽：单元格高度在两种模式下逐位相同，字体家族、
字号、字重、字形比例与回退顺序均不受影响。`refresh_ui_font` 计算的 Nebula
原生界面字体单元格固定按向下取整，不随该偏好变化。

切换时重推当前字体，让既有的字体更新路径重算单元格，网格、viewport、pane、
渲染器与 PTY 一致更新，无需重启。

nebula_app/src/display/mod.rs

@@ -132,8 +132,8 @@ pub(crate) use ui::theme::write_nebula_prompt_theme;
 pub(crate) fn caret_blink_on() -> bool {
     ui::caret::is_on()
 }
-pub(crate) use settings::SettingsOpacityTarget;
 pub use settings::{NebulaSettingsSection, SettingsDropdown, SettingsHit, settings_hit};
+pub(crate) use settings::{CellWidthMode, SettingsOpacityTarget};
 
 /// 按显示列宽贪心断行（确认框正文等 UI 段落用）：CJK 逐字可断，行首空
 /// 格吞掉；零宽字符跟随前一个字。不做拉丁连词回退——正文以中文为主，
@@ -1450,6 +1450,9 @@ pub struct Display {
     /// 捕获态实时回显：当前按住的修饰键前缀（"Ctrl+Shift+"）。松开清空。
     pub nebula_keymap_capture_preview: String,
     pub nebula_tab_reveal_motion: settings::TabRevealMotion,
+    /// 单元格宽度模式。只作用于终端内容网格；Nebula 原生界面的字体单元格
+    /// 始终按上游的向下取整计算，不随该偏好变化。
+    pub nebula_cell_width_mode: settings::CellWidthMode,
     pub nebula_font_family: String,
     nebula_font_families: Vec<String>,
     nebula_font_notice: Option<String>,
@@ -1707,7 +1710,8 @@ impl Display {
         crate::boot_trace("glyph cache (font faces loaded)");
 
         let metrics = glyph_cache.font_metrics();
-        let (cell_width, cell_height) = compute_cell_size(config, &metrics);
+        let (cell_width, cell_height) =
+            compute_cell_size(config, &metrics, settings_init.cell_width_mode);
 
         // Resize the window to the user-configured size, or a Windows
         // Terminal-like default when unset. A 116-column by 30-row canvas is
@@ -1725,7 +1729,9 @@ impl Display {
         let base_font_size = config.font.size().scale(scale_factor);
         let (base_cell_width, base_cell_height) = glyph_cache
             .metrics_at(base_font_size)
-            .map(|base_metrics| compute_cell_size(config, &base_metrics))
+            .map(|base_metrics| {
+                compute_cell_size(config, &base_metrics, settings_init.cell_width_mode)
+            })
             .unwrap_or((cell_width, cell_height));
         let size = window_size(
             config,
@@ -1968,6 +1974,7 @@ impl Display {
             nebula_keymap_capture: None,
             nebula_keymap_capture_preview: String::new(),
             nebula_tab_reveal_motion: settings_init.tab_reveal,
+            nebula_cell_width_mode: settings_init.cell_width_mode,
             nebula_font_family: settings_init.font_family,
             nebula_font_families,
             nebula_font_notice: None,
@@ -2992,6 +2999,7 @@ impl Display {
             panel_resize: self.nebula_panel_resize,
             cjk_bold_regular: self.nebula_cjk_bold_regular,
             tab_reveal: self.nebula_tab_reveal_motion,
+            cell_width_mode: self.nebula_cell_width_mode,
             preview_bg: self.preview_terminal_bg(),
             preview_fg: {
                 let bg = self.preview_terminal_bg();
@@ -3234,6 +3242,22 @@ impl Display {
         self.pending_update.dirty = true;
     }
 
+    /// 切换单元格宽度模式。列宽取整方式变了就必须重算单元格——重推当前
+    /// 字体让字体更新路径走一遍，网格、viewport、pane 与 PTY 随之一致更新，
+    /// 无需重启。字号、字体家族与行高都不变。
+    pub fn set_cell_width_mode_option(&mut self, index: usize, base: &Font) {
+        if let Some(mode) = settings::CELL_WIDTH_MODE_OPTIONS.get(index)
+            && *mode != self.nebula_cell_width_mode
+        {
+            self.nebula_cell_width_mode = *mode;
+            self.persist_nebula_settings();
+            let font = self.effective_font(base).with_size(self.font_size);
+            self.pending_update.set_font(font);
+        }
+        self.nebula_settings_dropdown = None;
+        self.pending_update.dirty = true;
+    }
+
     /// Returns true when the default cursor style changed (the caller then
     /// pushes the new default into every live terminal).
     pub fn set_cursor_shape_option(&mut self, index: usize) -> bool {
@@ -4518,7 +4542,10 @@ impl Display {
     fn refresh_ui_font(&mut self, config: &UiConfig) {
         let ui_size = FontSize::from_px(self.nebula_ui_font.px);
         let metrics = self.glyph_cache.set_ui_font_size(ui_size);
-        self.nebula_ui_font.cell = compute_cell_size(config, &metrics);
+        // 原生界面的字体单元格不受单元格宽度模式影响——该偏好只控制终端
+        // 内容网格的列宽。这里固定用上游的向下取整。
+        self.nebula_ui_font.cell =
+            compute_cell_size(config, &metrics, settings::CellWidthMode::Compact);
         let ratio = self.ui_text_scale();
         // Unconditional breadcrumb (tiny, a handful of lines per session):
         // diagnosing "the sidebar zooms with the terminal" reports needs this
@@ -4812,6 +4839,7 @@ impl Display {
             copy_on_select: self.nebula_copy_on_select,
             cjk_bold_regular: self.nebula_cjk_bold_regular,
             tab_reveal: self.nebula_tab_reveal_motion,
+            cell_width_mode: self.nebula_cell_width_mode,
             theme: self.nebula_theme_preference,
             follow_system_theme: self.nebula_follow_system_theme,
             pinned_hosts: self.nebula_pinned_hosts.clone(),
@@ -4909,6 +4937,7 @@ impl Display {
             self.reset_glyph_cache();
         }
         self.nebula_tab_reveal_motion = settings.tab_reveal;
+        self.nebula_cell_width_mode = settings.cell_width_mode;
         self.nebula_window_opacity = settings.opacity;
         self.nebula_background = if settings.follow_system_theme {
             Some(active_theme.palette().term_bg)
@@ -5129,11 +5158,12 @@ impl Display {
         glyph_cache: &mut GlyphCache,
         config: &UiConfig,
         font: &Font,
+        cell_width_mode: settings::CellWidthMode,
     ) -> (f32, f32) {
         let _ = glyph_cache.update_font_size(font);
 
         // Compute new cell sizes.
-        compute_cell_size(config, &glyph_cache.font_metrics())
+        compute_cell_size(config, &glyph_cache.font_metrics(), cell_width_mode)
     }
 
     /// Reset glyph cache.
@@ -5173,7 +5203,9 @@ impl Display {
 
         // Update font size and cell dimensions.
         if let Some(font) = pending_update.font() {
-            let cell_dimensions = Self::update_font_size(&mut self.glyph_cache, config, font);
+            let cell_width_mode = self.nebula_cell_width_mode;
+            let cell_dimensions =
+                Self::update_font_size(&mut self.glyph_cache, config, font, cell_width_mode);
             cell_width = cell_dimensions.0;
             cell_height = cell_dimensions.1;
 
@@ -8132,13 +8164,21 @@ impl FrameTimer {
 ///
 /// This will return a tuple of the cell width and height.
 #[inline]
-fn compute_cell_size(config: &UiConfig, metrics: &crossfont::Metrics) -> (f32, f32) {
+fn compute_cell_size(
+    config: &UiConfig,
+    metrics: &crossfont::Metrics,
+    cell_width_mode: settings::CellWidthMode,
+) -> (f32, f32) {
     let offset_x = f64::from(config.font.offset.x);
     let offset_y = f64::from(config.font.offset.y);
-    (
-        (metrics.average_advance + offset_x).floor().max(1.) as f32,
-        (metrics.line_height + offset_y).floor().max(1.) as f32,
-    )
+    // 宽度取整方式由单元格宽度模式决定；高度始终向下取整，两种模式必须
+    // 得到逐位相同的高度——该偏好只控制列宽。
+    let raw_width = metrics.average_advance + offset_x;
+    let width = match cell_width_mode {
+        settings::CellWidthMode::Compact => raw_width.floor(),
+        settings::CellWidthMode::Relaxed => raw_width.round(),
+    };
+    (width.max(1.) as f32, (metrics.line_height + offset_y).floor().max(1.) as f32)
 }
 
 /// Calculate the size of the window given padding, terminal dimensions and cell size.
@@ -8177,11 +8217,77 @@ mod nebula_ux_tests {
 
     use super::{
         AI_LOGO_GROK_DARK_PNG, AI_LOGO_GROK_LIGHT_PNG, AiLogo, NebulaConfirm, SizeInfo, ai_logo,
-        alt_screen_vertical_padding_bands, extract_program, nebula_command_hint,
+        alt_screen_vertical_padding_bands, compute_cell_size, extract_program, nebula_command_hint,
         percent_decode_lossy, prepare_ai_logo_texture, program_icon, remove_ssh_host_from_lists,
         replays_untrusted_terminal_output, restore_ssh_host_to_lists, strip_file_scheme,
         system_theme_snapshot,
     };
+    use crate::config::UiConfig;
+    use crate::display::settings::CellWidthMode;
+
+    /// 受控字体度量：只有 advance 与 line_height 参与单元格尺寸计算，
+    /// 其余字段取任意合法值。
+    fn metrics(average_advance: f64, line_height: f64) -> crossfont::Metrics {
+        crossfont::Metrics {
+            average_advance,
+            line_height,
+            descent: -4.0,
+            underline_position: -2.0,
+            underline_thickness: 1.0,
+            strikeout_position: 5.0,
+            strikeout_thickness: 1.0,
+        }
+    }
+
+    #[test]
+    fn relaxed_cell_width_rounds_up_the_fraction_compact_floors_it() {
+        let config = UiConfig::default();
+        // Maple Mono NF CN 这类字体的平均 advance 常落在 .5 以上，紧凑向下
+        // 取整因此比 Windows Terminal 少一像素——宽松就是为补这一像素而设。
+        let m = metrics(9.6, 20.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Compact).0, 9.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Relaxed).0, 10.0);
+    }
+
+    #[test]
+    fn a_fraction_below_half_stays_on_the_same_column_width_in_both_modes() {
+        let config = UiConfig::default();
+        let m = metrics(9.4, 20.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Compact).0, 9.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Relaxed).0, 9.0);
+    }
+
+    #[test]
+    fn the_exact_half_boundary_rounds_away_from_zero_in_relaxed_mode() {
+        let config = UiConfig::default();
+        let m = metrics(9.5, 20.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Compact).0, 9.0);
+        assert_eq!(compute_cell_size(&config, &m, CellWidthMode::Relaxed).0, 10.0);
+    }
+
+    #[test]
+    fn both_modes_compute_the_same_cell_height() {
+        let config = UiConfig::default();
+        // 该偏好只控制列宽；高度必须逐位相同，否则行距会随模式漂移。
+        for (advance, line_height) in [(9.6, 20.7), (7.5, 16.5), (12.2, 25.9)] {
+            let m = metrics(advance, line_height);
+            let compact = compute_cell_size(&config, &m, CellWidthMode::Compact);
+            let relaxed = compute_cell_size(&config, &m, CellWidthMode::Relaxed);
+            assert_eq!(compact.1, relaxed.1, "line_height {line_height} 的高度在两模式间漂移");
+        }
+    }
+
+    #[test]
+    fn both_modes_share_the_same_minimum_cell_width() {
+        let config = UiConfig::default();
+        // 退化度量（字体加载异常）不能产出 0 宽单元格——那会让网格除零。
+        let m = metrics(0.3, 0.4);
+        let compact = compute_cell_size(&config, &m, CellWidthMode::Compact);
+        let relaxed = compute_cell_size(&config, &m, CellWidthMode::Relaxed);
+        assert_eq!(compact.0, 1.0);
+        assert_eq!(relaxed.0, 1.0);
+        assert_eq!(compact.1, relaxed.1, "退化度量下高度也不得随模式漂移");
+    }
 
     fn strings(values: &[&str]) -> Vec<String> {
         values.iter().map(|value| (*value).to_owned()).collect()

nebula_app/src/display/settings.rs

@@ -94,6 +94,7 @@ pub enum SettingsDropdown {
     Accept,
     CursorShape,
     TabReveal,
+    CellWidthMode,
     /// 背景色：色板网格 + 16 进制输入的专用浮层（不是通用行列表）。
     BackgroundColor,
 }
@@ -143,6 +144,9 @@ pub(super) const ACCEPT_OPTIONS: [AcceptKey; 3] =
 pub(super) const TAB_REVEAL_OPTIONS: [TabRevealMotion; 2] =
     [TabRevealMotion::Slide, TabRevealMotion::Instant];
 
+pub(super) const CELL_WIDTH_MODE_OPTIONS: [CellWidthMode; 2] =
+    [CellWidthMode::Compact, CellWidthMode::Relaxed];
+
 /// Order mirrors the appearance page the user referenced.
 pub(super) const CURSOR_SHAPE_OPTIONS: [CursorShape; 4] =
     [CursorShape::Beam, CursorShape::Underline, CursorShape::Block, CursorShape::HollowBlock];
@@ -178,6 +182,41 @@ fn tab_reveal_label(motion: TabRevealMotion, language: UiLanguage) -> &'static s
     }
 }
 
+/// 单元格宽度模式：终端把字体的非整数设计宽度转换为整像素列宽的方式。
+/// 「紧凑」保持上游的向下取整并作为兼容默认；「宽松」采用最接近整数取整，
+/// 补足与 Windows Terminal 相差的那一像素。它只影响列宽，不改变单元格高度、
+/// 字形比例或原生界面排版。
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub(crate) enum CellWidthMode {
+    #[default]
+    Compact,
+    Relaxed,
+}
+
+impl CellWidthMode {
+    fn parse(value: &str) -> Option<Self> {
+        match value.trim().to_ascii_lowercase().as_str() {
+            "compact" => Some(Self::Compact),
+            "relaxed" => Some(Self::Relaxed),
+            _ => None,
+        }
+    }
+
+    fn settings_value(self) -> &'static str {
+        match self {
+            Self::Compact => "compact",
+            Self::Relaxed => "relaxed",
+        }
+    }
+}
+
+fn cell_width_mode_label(mode: CellWidthMode, language: UiLanguage) -> &'static str {
+    match mode {
+        CellWidthMode::Compact => language.pick("紧凑", "Compact"),
+        CellWidthMode::Relaxed => language.pick("宽松", "Relaxed"),
+    }
+}
+
 pub(super) fn cursor_shape_label(shape: CursorShape, language: UiLanguage) -> &'static str {
     match shape {
         CursorShape::Beam => language.pick("条形（│）", "Bar (│)"),
@@ -240,6 +279,8 @@ pub enum SettingsHit {
     CjkBoldToggle,
     TabRevealDropdown,
     TabRevealOption(usize),
+    CellWidthModeDropdown,
+    CellWidthModeOption(usize),
     /// Language combobox trigger (options resolve to [`SettingsHit::Language`]).
     LanguageDropdown,
     /// Expanded dropdown option rows for the cycle-style settings.
@@ -309,6 +350,7 @@ pub(super) struct NebulaRuntimeSettings {
     /// 默认开：小字号下雅黑 Bold fallback 与 Regular 混排发闷（任务 #4）。
     pub(super) cjk_bold_regular: bool,
     pub(super) tab_reveal: TabRevealMotion,
+    pub(super) cell_width_mode: CellWidthMode,
     pub(super) fetch: bool,
     pub(super) powerline: bool,
     /// Window close keeps the PTYs alive in the resident process (detach /
@@ -381,6 +423,7 @@ pub(super) fn nebula_settings_load(config: &UiConfig) -> NebulaRuntimeSettings {
         copy_on_select: true,
         cjk_bold_regular: true,
         tab_reveal: TabRevealMotion::Slide,
+        cell_width_mode: CellWidthMode::Compact,
         // Off by default: the welcome screen pipes a whole script through the
         // fresh shell and repaints on resize — real startup-latency cost on
         // the critical path (user ruling: startup speed outranks the art).
@@ -468,6 +511,9 @@ pub(super) fn nebula_settings_load(config: &UiConfig) -> NebulaRuntimeSettings {
                 Some(("tab_reveal", v)) => {
                     settings.tab_reveal = TabRevealMotion::parse(v).unwrap_or_default();
                 },
+                Some(("cell_width_mode", v)) => {
+                    settings.cell_width_mode = CellWidthMode::parse(v).unwrap_or_default();
+                },
                 Some(("startup_directory", v)) => {
                     let path = std::path::PathBuf::from(v.trim());
                     if path.is_dir() {
@@ -681,7 +727,7 @@ pub(super) fn nebula_settings_write(settings: &NebulaRuntimeSettings) {
         path,
         format!(
             "language={}\ntheme={theme}\nfollow_system_theme={}\nghost={}\naccept={accept}\nshell={shell}\nstartup_directory={startup_directory}\nfont_family={}\nfont_size={font_size}\ncursor_shape={}\ncursor_blink={}\ncopy_on_select={}\ncjk_bold_regular={}
-tab_reveal={}\nfetch={}\npowerline={}\nkeep_session={}\nrestore_session={}\nblur={}\nopacity={:.2}\nbackground={background}\nbackground_image={background_image}\nbackground_image_opacity={:.2}\nbackground_image_fit={}\nbackground_image_alignment={}\nbackground_image_cover_chrome={}\npanel_resize={}\nsidebar_w={:.0}\ndrawer_w={:.0}\nhosts_band={:.0}\npinned_hosts={pinned_hosts}\nsaved_hosts={saved_hosts}\nhidden_hosts={hidden_hosts}\nquick_terminal_hotkey={quick_terminal_hotkey}\n{keybinds}",
+tab_reveal={}\ncell_width_mode={}\nfetch={}\npowerline={}\nkeep_session={}\nrestore_session={}\nblur={}\nopacity={:.2}\nbackground={background}\nbackground_image={background_image}\nbackground_image_opacity={:.2}\nbackground_image_fit={}\nbackground_image_alignment={}\nbackground_image_cover_chrome={}\npanel_resize={}\nsidebar_w={:.0}\ndrawer_w={:.0}\nhosts_band={:.0}\npinned_hosts={pinned_hosts}\nsaved_hosts={saved_hosts}\nhidden_hosts={hidden_hosts}\nquick_terminal_hotkey={quick_terminal_hotkey}\n{keybinds}",
             settings.language.as_str(),
             settings.follow_system_theme as u8,
             settings.ghost as u8,
@@ -691,6 +737,7 @@ tab_reveal={}\nfetch={}\npowerline={}\nkeep_session={}\nrestore_session={}\nblur
             settings.copy_on_select as u8,
             settings.cjk_bold_regular as u8,
             settings.tab_reveal.settings_value(),
+            settings.cell_width_mode.settings_value(),
             settings.fetch as u8,
             settings.powerline as u8,
             settings.keep_session as u8,
@@ -729,6 +776,7 @@ struct SettingsGeometry {
     font: (f32, f32, f32, f32),
     /// "字号" spinner row; the value box + steppers derive via `widgets`.
     font_size_row: (f32, f32, f32, f32),
+    cell_width_mode: (f32, f32, f32, f32),
     fetch: (f32, f32, f32, f32),
     powerline: (f32, f32, f32, f32),
     ghost: (f32, f32, f32, f32),
@@ -923,7 +971,8 @@ fn settings_geometry(
     let startup_directory_y0 = shell_y0 + ROW_H;
     let font_y0 = startup_directory_y0 + ROW_H;
     let font_size_y0 = font_y0 + ROW_H;
-    let fetch_y0 = font_size_y0 + ROW_H;
+    let cell_width_mode_y0 = font_size_y0 + ROW_H;
+    let fetch_y0 = cell_width_mode_y0 + ROW_H;
     let ghost_y0 = fetch_y0 + 2.0 * ROW_H + GROUP_ADVANCE;
     let open_y0 = ghost_y0 + 2.0 * ROW_H + GROUP_ADVANCE;
     let hidden_y0 = open_y0 + ROW_H + GROUP_ADVANCE;
@@ -1010,6 +1059,7 @@ fn settings_geometry(
         ),
         font: (row_x, at(font_y0), row_w, row_h),
         font_size_row: (row_x, at(font_size_y0), row_w, row_h),
+        cell_width_mode: (row_x, at(cell_width_mode_y0), row_w, row_h),
         fetch: (row_x, at(fetch_y0), row_w, row_h),
         powerline: (row_x, at(fetch_y0 + ROW_H), row_w, row_h),
         ghost: (row_x, at(ghost_y0), row_w, row_h),
@@ -1135,6 +1185,9 @@ fn dropdown_anchor(
         (Section::Profiles, SettingsDropdown::Accept) => {
             Some((anchor(geometry.accept), ACCEPT_OPTIONS.len()))
         },
+        (Section::Profiles, SettingsDropdown::CellWidthMode) => {
+            Some((anchor(geometry.cell_width_mode), CELL_WIDTH_MODE_OPTIONS.len()))
+        },
         (Section::Interaction, SettingsDropdown::TabReveal) => {
             Some((anchor(geometry.tab_reveal), TAB_REVEAL_OPTIONS.len()))
         },
@@ -1226,6 +1279,7 @@ pub fn settings_hit(
                     SettingsDropdown::Language => SettingsHit::Language(LANGUAGE_OPTIONS[index]),
                     SettingsDropdown::Accept => SettingsHit::AcceptOption(index),
                     SettingsDropdown::TabReveal => SettingsHit::TabRevealOption(index),
+                    SettingsDropdown::CellWidthMode => SettingsHit::CellWidthModeOption(index),
                     SettingsDropdown::CursorShape => SettingsHit::CursorShapeOption(index),
                     // 背景色浮层在上方特判处理，走不到通用行列表。
                     SettingsDropdown::BackgroundColor => SettingsHit::Panel,
@@ -1321,6 +1375,9 @@ pub fn settings_hit(
                         return SettingsHit::FontSizeDown;
                     }
                 }
+                if contains_rect(geometry.cell_width_mode, x, y) {
+                    return SettingsHit::CellWidthModeDropdown;
+                }
                 if contains_rect(geometry.fetch, x, y) {
                     return SettingsHit::FetchToggle;
                 }
@@ -1451,6 +1508,7 @@ pub(super) struct SettingsView {
     pub(super) panel_resize: bool,
     pub(super) cjk_bold_regular: bool,
     pub(super) tab_reveal: TabRevealMotion,
+    pub(super) cell_width_mode: CellWidthMode,
     /// Live-preview colors: the ACTUAL terminal background/foreground the
     /// grid would use right now (custom background wins over the theme).
     pub(super) preview_bg: Rgb,
@@ -1617,6 +1675,9 @@ fn dropdown_selected_index(view: &SettingsView, dropdown: SettingsDropdown) -> O
         SettingsDropdown::TabReveal => {
             TAB_REVEAL_OPTIONS.iter().position(|motion| *motion == view.tab_reveal)
         },
+        SettingsDropdown::CellWidthMode => {
+            CELL_WIDTH_MODE_OPTIONS.iter().position(|mode| *mode == view.cell_width_mode)
+        },
         SettingsDropdown::CursorShape => {
             CURSOR_SHAPE_OPTIONS.iter().position(|shape| *shape == view.cursor_shape)
         },
@@ -1637,6 +1698,7 @@ fn dropdown_hover_index(hover: SettingsHit, dropdown: SettingsDropdown) -> Optio
         },
         (SettingsDropdown::Accept, SettingsHit::AcceptOption(index)) => Some(index),
         (SettingsDropdown::TabReveal, SettingsHit::TabRevealOption(index)) => Some(index),
+        (SettingsDropdown::CellWidthMode, SettingsHit::CellWidthModeOption(index)) => Some(index),
         (SettingsDropdown::CursorShape, SettingsHit::CursorShapeOption(index)) => Some(index),
         _ => None,
     }
@@ -2172,6 +2234,18 @@ pub(super) fn push_quads(
                 view.hover == SettingsHit::FontSizeUp,
                 view.hover == SettingsHit::FontSizeDown,
             );
+            row_hover(
+                quads,
+                geometry.cell_width_mode,
+                view.hover == SettingsHit::CellWidthModeDropdown,
+            );
+            combobox(
+                quads,
+                &mut staged,
+                geometry.cell_width_mode,
+                view.hover == SettingsHit::CellWidthModeDropdown,
+                view.dropdown == Some(SettingsDropdown::CellWidthMode),
+            );
             for quad in staged.drain(..) {
                 clip(quads, quad);
             }
@@ -2604,6 +2678,9 @@ pub(super) fn draw_popup_text(
             SettingsDropdown::TabReveal => {
                 tab_reveal_label(TAB_REVEAL_OPTIONS[index], language).to_owned()
             },
+            SettingsDropdown::CellWidthMode => {
+                cell_width_mode_label(CELL_WIDTH_MODE_OPTIONS[index], language).to_owned()
+            },
             SettingsDropdown::CursorShape => {
                 cursor_shape_label(CURSOR_SHAPE_OPTIONS[index], language).to_owned()
             },
@@ -3329,6 +3406,26 @@ pub(super) fn draw_text(
                     gc,
                 );
             }
+            if visible(geometry.cell_width_mode.1, geometry.cell_width_mode.3) {
+                row_label(
+                    r,
+                    gc,
+                    size,
+                    scale,
+                    &sk,
+                    geometry.cell_width_mode,
+                    language.pick("字体间距", "Font spacing"),
+                    "",
+                    sk.ink,
+                );
+                combobox_value(
+                    r,
+                    gc,
+                    geometry.cell_width_mode,
+                    cell_width_mode_label(view.cell_width_mode, language),
+                    sk.accent,
+                );
+            }
             // Boolean rows: the switch (drawn in `push_quads`) carries the
             // state; no "On/Off" string next to it.
             if visible(geometry.fetch.1, geometry.fetch.3) {
@@ -3829,7 +3926,8 @@ pub(super) fn draw_text(
 #[cfg(test)]
 mod tests {
     use super::{
-        SHOW_WEBDAV_SYNC_SETTINGS, TabRevealMotion, advanced_content_end, opacity_from_pointer,
+        CELL_WIDTH_MODE_OPTIONS, CellWidthMode, SHOW_WEBDAV_SYNC_SETTINGS, TabRevealMotion,
+        UiLanguage, advanced_content_end, cell_width_mode_label, opacity_from_pointer,
     };
 
     #[test]
@@ -3860,4 +3958,27 @@ mod tests {
             assert_eq!(TabRevealMotion::parse(value.settings_value()), Some(value));
         }
     }
+
+    #[test]
+    fn cell_width_mode_defaults_compatibly_and_round_trips() {
+        assert_eq!(CellWidthMode::default(), CellWidthMode::Compact);
+        assert_eq!(CellWidthMode::parse("compact"), Some(CellWidthMode::Compact));
+        assert_eq!(CellWidthMode::parse("RELAXED"), Some(CellWidthMode::Relaxed));
+        assert_eq!(CellWidthMode::parse("unknown").unwrap_or_default(), CellWidthMode::Compact);
+        for value in [CellWidthMode::Compact, CellWidthMode::Relaxed] {
+            assert_eq!(CellWidthMode::parse(value.settings_value()), Some(value));
+        }
+    }
+
+    #[test]
+    fn cell_width_mode_dropdown_offers_both_choices_with_the_compatible_one_first() {
+        // 列表顺序即下拉顺序，也是持久化索引的来源；兼容默认必须排第一。
+        assert_eq!(CELL_WIDTH_MODE_OPTIONS.len(), 2);
+        assert_eq!(CELL_WIDTH_MODE_OPTIONS[0], CellWidthMode::default());
+        assert_eq!(CELL_WIDTH_MODE_OPTIONS[1], CellWidthMode::Relaxed);
+        for option in CELL_WIDTH_MODE_OPTIONS {
+            assert!(!cell_width_mode_label(option, UiLanguage::ZhCn).is_empty());
+            assert!(!cell_width_mode_label(option, UiLanguage::EnUs).is_empty());
+        }
+    }
 }

nebula_app/src/input/chrome.rs

@@ -862,6 +862,19 @@ impl<T: EventListener, A: ActionContext<T>> Processor<T, A> {
                         self.ctx.mark_dirty();
                         return;
                     },
+                    crate::display::SettingsHit::CellWidthModeDropdown => {
+                        self.ctx.display().toggle_settings_dropdown(
+                            crate::display::SettingsDropdown::CellWidthMode,
+                        );
+                        self.ctx.mark_dirty();
+                        return;
+                    },
+                    crate::display::SettingsHit::CellWidthModeOption(index) => {
+                        let base_font = self.ctx.config().font.clone();
+                        self.ctx.display().set_cell_width_mode_option(index, &base_font);
+                        self.ctx.mark_dirty();
+                        return;
+                    },
                     crate::display::SettingsHit::FontSizeUp => {
                         let ui_scale = self.ctx.display().window.scale_factor as f32;
                         self.ctx.change_font_size(ui_scale);
@@ -1292,6 +1305,8 @@ fn settings_dropdown_keeps_open(hit: crate::display::SettingsHit) -> bool {
             | Hit::AcceptOption(_)
             | Hit::TabRevealDropdown
             | Hit::TabRevealOption(_)
+            | Hit::CellWidthModeDropdown
+            | Hit::CellWidthModeOption(_)
             | Hit::CursorShapeDropdown
             | Hit::CursorShapeOption(_)
             | Hit::BackgroundColor

nebula_app/src/input/mouse.rs

@@ -331,6 +331,8 @@ impl<T: EventListener, A: ActionContext<T>> Processor<T, A> {
             | crate::display::SettingsHit::KeymapRow(_)
             | crate::display::SettingsHit::TabRevealDropdown
             | crate::display::SettingsHit::TabRevealOption(_)
+            | crate::display::SettingsHit::CellWidthModeDropdown
+            | crate::display::SettingsHit::CellWidthModeOption(_)
             | crate::display::SettingsHit::FontSizeUp
             | crate::display::SettingsHit::FontSizeDown
             | crate::display::SettingsHit::BackgroundImageCoverChrome