How do I create a multiple-selection dropdown menu using checkboxes in HTML and CSS?

How to Integrate Checkboxes into a Dropdown Menu

Creating a multiple-selection dropdown list allows users to select multiple options conveniently. Although you might be tempted to use a simple checkbox in front of the dropdown field, this method displays the checkbox for the entire list instead of for each option. To achieve the desired functionality, follow these steps:

Creating a Dropdown Checklist:

Consider the following HTML and CSS code to create a simple dropdown checklist:

<div>
<pre class="brush:php;toolbar:false">.dropdown-check-list {
  display: inline-block;
}

.dropdown-check-list .anchor {
  position: relative;
  cursor: pointer;
  display: inline-block;
  padding: 5px 50px 5px 10px;
  border: 1px solid #ccc;
}

.dropdown-check-list .anchor:after {
  position: absolute;
  content: "";
  border-left: 2px solid black;
  border-top: 2px solid black;
  padding: 5px;
  right: 10px;
  top: 20%;
  -moz-transform: rotate(-135deg);
  -ms-transform: rotate(-135deg);
  -o-transform: rotate(-135deg);
  -webkit-transform: rotate(-135deg);
  transform: rotate(-135deg);
}

.dropdown-check-list .anchor:active:after {
  right: 8px;
  top: 21%;
}

.dropdown-check-list ul.items {
  padding: 2px;
  display: none;
  margin: 0;
  border: 1px solid #ccc;
  border-top: none;
}

.dropdown-check-list ul.items li {
  list-style: none;
}

.dropdown-check-list.visible .anchor {
  color: #0094ff;
}

.dropdown-check-list.visible .items {
  display: block;
}

JavaScript can be used to control the visibility of the checkbox list.

var checkList = document.getElementById('list1');
checkList.getElementsByClassName('anchor')[0].onclick = function(evt) {
  if (checkList.classList.contains('visible'))
    checkList.classList.remove('visible');
  else
    checkList.classList.add('visible');
};

Result:

This solution creates a dropdown menu where you can select multiple options by checking the checkboxes. The "anchor" element acts as a button to open and close the checkbox list. Styling can be customized as needed to match your website's design.