Close alert messages with a button

HTML

<div class="alert alert-primary">
  歡迎您點擊「抖內」按鈕，以實際行動支持我們。
  <button class="btn-close">x</button>
</div>
<br><hr><br>
<div class="alert alert-success">
  您已成功下訂單!以下為您的訂單詳細資訊。
  <button class="btn-close">x</button>
</div>
<br><hr><br>
<div class="alert alert-danger">
  抱歉，系統發生錯誤，請稍後重新嘗試。
  <button class="btn-close">x</button>
</div>
<br><hr><br>
<div class="alert alert-warning">
  請注意，以下內容包含「據透」爆雷資訊。
  <button class="btn-close">x</button>
</div>

CSS

.alert-primary {
  background-color:#e6effa;
  border-color: #bcd4ee;
}
.alert-success {
  background-color: #eaf7ee;
  border-color: #c9ced0;
}
.alert-danger {
  background-color:  #fcede9;
  border-color: #f2ded9;
}

.alert-warning {
  background-color:#fef7ea ;
  border-color:#fde8c8 ;
}
* {
  box-sizing: border-box;
}
.alert {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 500px;
  margin: 0 auto;
  height: 2.5rem;
  border-radius: 8px;
  padding: 0 10px;
  font-size: 18px;
}

.btn-close {
  background-color: transparent;
  border: none;
  cursor: pointer;
  font-size: 24px;
  border-radius: 8px;
}
.btn-close:hover {
  background-color: rgba(255, 255, 255, 0.7);
}

JavaScript

const closeButtons = document.querySelectorAll('.btn-close');

function removeAlert() {
  event.target.closest('.alert').remove();

}

for(let closeButton of closeButtons) {
  closeButton.onclick = removeAlert;
}