Formatting

csskit comes with a CSS code formatter built in. Use csskit fmt to format your CSS files for better readability and consistency.

Quick Start

Format a single file:

csskit fmt styles.css

Format multiple files:

csskit fmt styles.css theme.css components.css

Format from stdin (useful for piping):

cat styles.css | csskit fmt
echo "body{margin:0}" | csskit fmt

By default, csskit fmt writes formatted output to stdout. Use -o to write to a file:

csskit fmt input.css -o output.css

Options

Tab Expansion

By default csskit fmt will use tabs for indentation. If you prefer spaces over tabs, add --expand-tab N and it will expand tabs into N space characters:

csskit fmt --expand-tab 2 styles.css

Quote Style

By default csskit fmt will use double quotes for strings. If you prefer single quote characters over double quotes, add --single-quotes:

csskit fmt --single-quotes styles.css

Example:

Input:

div {
	content: "hello world";
	font-family: "Arial", "Helvetica", sans-serif;
}

Output:

div {
	content: "hello world";
	font-family: 'Arial', 'Helvetica', sans-serif;
}

Check Mode

Use --check to verify if files need formatting without making changes. This is useful in CI/CD pipelines:

csskit fmt --check styles.css

This will:

Exit with status code 0 if no changes needed
Exit with non-zero status code if formatting would change the file
Report which changes would be made without writing them

Example in CI:

# Fail the build if CSS isn't formatted
csskit fmt --check src/**/*.css

Processing Content Directly

Use --content (or -c) to format CSS content directly from the command line:

csskit fmt -c "body{margin:0;padding:0}"