参加聚会的时间很少（非常），但是仍然如此。这应该做的伎俩：

function closest(el, selector) {
    var matchesFn;

    // find vendor prefix
    ['matches','webkitMatchesSelector','mozMatchesSelector','msMatchesSelector','oMatchesSelector'].some(function(fn) {
        if (typeof document.body[fn] == 'function') {
            matchesFn = fn;
            return true;
        }
        return false;
    })

    var parent;

    // traverse parents
    while (el) {
        parent = el.parentElement;
        if (parent && parent[matchesFn](selector)) {
            return parent;
        }
        el = parent;
    }

    return null;
}