fix: Match bat in gutter coloring

Cargo.toml

@@ -48,3 +48,4 @@ encoding = "0.2.33"
 git-config-env = "0.1.2"
 shlex = "1.1.0"
 atty = "0.2.14"
+anstyle-syntect = "0.1.2"

src/blame.rs

@@ -100,22 +100,11 @@ pub fn blame(
     } else {
         "".to_owned()
     };
-    let gutter_style = anstyle::Style::new()
-        .fg_color(
-            highlighter
-                .theme()
-                .settings
-                .gutter_foreground
-                .map(|c| (c.r, c.g, c.b).into()),
-        )
-        .bg_color(
-            highlighter
-                .theme()
-                .settings
-                .gutter
-                .map(|c| (c.r, c.g, c.b).into()),
-        );
-    let gutter_style = gutter_style.render();
+    let gutter_style = if colored_stdout {
+        gutter_style(highlighter.theme()).render().to_string()
+    } else {
+        "".to_owned()
+    };
     let wrap = textwrap::Options::new(code_width)
         .break_words(false)
         .wrap_algorithm(textwrap::WrapAlgorithm::FirstFit);
@@ -436,6 +425,19 @@ impl<'a> Highlighter<'a> {
     }
 }
 
+fn gutter_style(theme: &syntect::highlighting::Theme) -> anstyle::Style {
+    const DEFAULT_GUTTER_COLOR: u8 = 238;
+
+    // If the theme provides a gutter foreground color, use it.
+    let fg_color = theme
+        .settings
+        .gutter_foreground
+        .map(anstyle_syntect::to_anstyle_color)
+        .unwrap_or_else(|| anstyle::XTermColor(DEFAULT_GUTTER_COLOR).into());
+
+    fg_color.into()
+}
+
 const THEME_DEFAULT: &str = "base16-ocean.dark";
 pub const THEME: DefaultField<String> =
     RawField::<String>::new("dive.theme").default_value(|| THEME_DEFAULT.to_owned());