Repository: gohugoio/hugo (language: go)

Issue:
Chromastyles for line highlighting isn't using the correct color
### What version of Hugo are you using (`hugo version`)?

```shell
hugo v0.118.2-da7983ac4b94d97d776d7c2405040de97e95c03d+extended darwin/amd64 BuildDate=2023-08-31T11:23:51Z VendorInfo=brew
```

### Does this issue reproduce with the latest release?
Yes.


### What are the steps to reproduce?
Using the command found in the documentation at https://gohugo.io/content-management/syntax-highlighting/#generate-syntax-highlighter-css 

```bash
hugo gen chromastyles --style=monokai > syntax.css
```

This generates a css file where the line highlight is the following.

```css
/* LineHighlight */ .chroma .hl { background-color: #ffffcc }
```

When you run chroma by itself using the following command

```bash
chroma -s monokai --html-styles --style=monokai
```
it will generate the following css

```css
/* LineHighlight */ .chroma .hl { background-color: #3c3d38 }
```


Discussion / hints:

Fix patch:
diff --git a/commands/gen.go b/commands/gen.go
index 4b96ffc5c58..534eb0df5a1 100644
--- a/commands/gen.go
+++ b/commands/gen.go
@@ -76,7 +76,7 @@ See https://xyproto.github.io/splash/docs/all.html for a preview of the availabl
 			},
 			withc: func(cmd *cobra.Command, r *rootCommand) {
 				cmd.PersistentFlags().StringVar(&style, "style", "friendly", "highlighter style (see https://xyproto.github.io/splash/docs/)")
-				cmd.PersistentFlags().StringVar(&highlightStyle, "highlightStyle", "bg:#ffffcc", "style used for highlighting lines (see https://github.com/alecthomas/chroma)")
+				cmd.PersistentFlags().StringVar(&highlightStyle, "highlightStyle", "", "style used for highlighting lines (see https://github.com/alecthomas/chroma)")
 				cmd.PersistentFlags().StringVar(&linesStyle, "linesStyle", "", "style used for line numbers (see https://github.com/alecthomas/chroma)")
 			},
 		}
@@ -136,7 +136,7 @@ url: %s
 			long: `Generate Markdown documentation for the Hugo CLI.
 			This command is, mostly, used to create up-to-date documentation
 	of Hugo's command-line interface for https://gohugo.io/.
-	
+
 	It creates one Markdown file per command with front matter suitable
 	for rendering in Hugo.`,
 			run: func(ctx context.Context, cd *simplecobra.Commandeer, r *rootCommand, args []string) error {


Test patch:
diff --git a/testscripts/commands/gen.txt b/testscripts/commands/gen.txt
index 891079e11bc..e11ba064266 100644
--- a/testscripts/commands/gen.txt
+++ b/testscripts/commands/gen.txt
@@ -16,4 +16,4 @@ checkfilecount $NUM_COMMANDS manpages
 hugo gen chromastyles -h
 stdout 'Generate CSS stylesheet for the Chroma code highlighter'
 hugo gen chromastyles --style monokai
-stdout 'color: #f8f8f2'
\ No newline at end of file
+stdout '/\* LineHighlight \*/ \.chroma \.hl \{ background-color: #3c3d38 \}'