[Malleys]

misha.korolcov, заведите массив языков и сравнивайте...

var cfg = {
	langs: "zh,en,ar,fr,de,se,ru,fi,gr".split(","),
	baseURL: "http://localhost:8000/"
};

if (
	document.location.href == cfg.baseURL ||
	cfg.langs.some(lang => document.location.href == cfg.baseURL + lang)
) {
	$("#main-navigation #second-bar").css("background", "#0D0E14");
	$("#second-bar a").css("border", "1px solid #0D0E14");
	$(".under-menu").css("background", "#1B1C28");
}