MikUrrey

const findByKey = (object, key) => {
 if (object instanceof Array) {
  for (let i = 0; i < object.length; i++) {
    let result = findByKey(object[i], key);
    if (result  !== null) {
     return result;
    }
  }
  return null;
 }
 for (let p in object) {
  if (p === key) {
   return object[p]
  } else if (typeof object[p] === 'object') {
   let result = findByKey(object[p], key);
   if (result  !== null) {
    return result;
   }
  }
 }
 return null;
}

findByKey(someObject, someKey)

$('.close').on('click', function (e) {
  e.stopPropagation(); // вот так
  $('.section').removeClass('opened');
});