func Splash(htmlData []byte, styleName string) ([]byte, error) {
	return highlightPre(htmlData, styleName, false)
}
Splash takes HTML code as bytes and tries to syntax highlight code between
<pre> and </pre> tags.

"style" is a syntax highlight style, like "monokai".

Full style list here: https://github.com/alecthomas/chroma/tree/master/styles

Returns the modified HTML source code with embedded CSS as a <style> tag.
Requires the given HTML to contain </head> or <html>.

language specifiers like <code class="language-c"> are supported.
package splash
import (
	"bytes"
	"errors"
	"html"
	"regexp"
	"unicode"
	"github.com/alecthomas/chroma"
	chromaHTML "github.com/alecthomas/chroma/formatters/html"
	"github.com/alecthomas/chroma/lexers"
	"github.com/alecthomas/chroma/styles"
)
var (
	errHEAD = errors.New("HTML should contain <head> or <html> when adding CSS")
	defaultLanguage = "shell"
)