Как выглядит примерный код выпадающего навигационного меню на Javascript?

< style >
.dropbtn {
background-color: #4CAF50;
color: white;
padding: 16px;
font-size: 16px;
border: none;
cursor: pointer;
}

.dropbtn:hover, .dropbtn:focus {
background-color: #3e8e41;
}

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

.dropdown-content {
display: none;
position: absolute;
background-color: #f9f9f9;
min-width: 160px;
overflow: auto;
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
}

.dropdown-content a {
color: black;
padding: 12px 16px;
text-decoration: none;
display: block;
}

.dropdown a:hover {background-color: #f1f1f1}

.show {display:block;}
< /style >

Clickable Dropdown
Click on the button to open the dropdown menu.

< div class="dropdown" >
< button onclick="myFunction()" class="dropbtn" >Dropdown< /button >
< div id="myDropdown" class="dropdown-content" >
< a href="#home">Home< /a >
< a href="#about">About< /a >
< a href="#contact" > Contact< /a >
< /div >
< /div >

< script >
/* When the user clicks on the button,
toggle between hiding and showing the dropdown content */
function myFunction() {
document.getElementById("myDropdown").classList.toggle("show");
}

// Close the dropdown if the user clicks outside of it
window.onclick = function(event) {
if (!event.target.matches('.dropbtn')) {

var dropdowns = document.getElementsByClassName("dropdown-content");
var i;
for (i = 0; i < dropdowns.length; i++) {
var openDropdown = dropdowns[i];
if (openDropdown.classList.contains('show')) {
openDropdown.classList.remove('show');
}
}
}
}
< /script >

nav ul {display: none}
nav li:hover > ul {display: block}