Personal-Website/themes/maik-blog/assets/js/menu.js

// Mobile menu

const menuTrigger = document.querySelector(".menu-trigger");
const menu = document.querySelector(".menu");
const mobileQuery = getComputedStyle(document.body).getPropertyValue(
    "--phoneWidth"
);
const isMobile = () => window.matchMedia(mobileQuery).matches;
const isMobileMenu = () => {
    menuTrigger && menuTrigger.classList.toggle("hidden", !isMobile());
    menu && menu.classList.toggle("hidden", isMobile());
};

isMobileMenu();

menuTrigger &&
    menuTrigger.addEventListener(
        "click",
        () => menu && menu.classList.toggle("hidden")
    );

window.addEventListener("resize", isMobileMenu);