Как закрыть выпадающий список кнопкой его открытия

.btn {
  background-color: rgba(080, 080, 080, 0.79);
  color: white;
  padding: 5px;
  font-size: 14px;
  border: none;
  outline: none;
  margin-bottom: 7px;
  margin-top: 7px;
  border-bottom-right-radius: 20px;
  border-top-right-radius: 20px;
}

.btn2 {
  background-color: rgba(080, 080, 080, 0.79);
  color: white;
  padding: 5px;
  font-size: 14px;
  border: none;
  outline: none;
  margin-bottom: 7px;
  margin-top: 7px;
  border-bottom-left-radius: 20px;
  border-top-left-radius: 20px;
}

.dropdown {
  position: absolute;
  display: inline-block;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: rgba(028, 028, 028, 0.79);
  backdrop-filter: blur(10px);
  min-width: 160px;
  z-index: 1;
  border-radius: 15px;
  text-align: center;
  font-size: 14px;
  padding: 4px;
}

.dropdown:hover .dropdown-content {
  display: block;
}

<div id="mobile-sort">
  <button class="btn2">•</button>
  <div class="dropdown">
    <button class="btn">
      Сортировать <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content">
      <button class="sort-asc">1</button><br>
      <button class="sort-desc">2</button><br>
      <button class="sort-rating">3</button><br>
      <button class="sort-gift">4</button>
    </div>
  </div>
</div>