Source: https://stackoverflow.com/a/3028037
function hideOnClickOutside(element) {
    const outsideClickListener = event => {
        if (!element.contains(event.target)) { // or use: event.target.closest(selector) === null
            if (isVisible(element)) {
                element.style.display = 'none'
                removeClickListener()
            }
        }
    }
    const removeClickListener = () => {
        document.removeEventListener('click', outsideClickListener)
    }
    document.addEventListener('click', outsideClickListener)
}
112800cookie-checkJavascript: Hide on click outside element