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<html>
<head>
<!-- HTML HEAD CONTENT -->
</head>
<body>
<header>
<nav>
<ul>
<li>
<a href="#">Link</a>
<ul>
<li>
<a href="#">Link</a>
</li>
<li>
<a href="#">Longer Link</a>
</li>
<li>
<a href="#">Link</a>
<ul>
<li>
<a href="#">Link</a>
</li>
<li>
<a href="#">Longer Link</a>
<ul>
<li>
<a href="#">Link</a>
</li>
<li>
<a href="#">Longer Link</a>
</li>
<li>
<a href="#">Link</a>
</li>
</ul>
</li>
<li>
<a href="#">Link</a>
</li>
</ul>
</li>
</ul>
</li>
<li>
<a href="#">Link</a>
</li>
<li>
<a href="#">Link</a>
</li>
<li>
<a href="#">Link</a>
</li>
</ul>
</nav>
</header>
<main></main>
<footer></main>
</body>
</html>
// The anchor point for every absolute positioned submenu is the parent li
nav li {
position: relative;
}
// First level of li should be next to each other
// Just using display: inline-block; on the first li elements
// would cause a space between the li`s
// see https://css-tricks.com/fighting-the-space-between-inline-block-elements/
nav > ul {
display: flex;
}
// Just a bit of styling for the link
// Always style the a, not the li
// Otherwise the end user is confused if he/she can't click the button
nav li a {
display: block;
padding: 10px 15px;
background: green;
border: 3px solid green;
font-size: 1.25em;
color: #fff;
text-decoration: none;
// Prevent whitespace wrapping if needed
white-space: nowrap;
transition: all .3s;
&:hover {
background: #fff;
color: green;
}
}
// initially hide every submenu and position it
nav ul ul {
visibility: hidden;
opacity: 0;
// If needed set a width for the submenu
min-width: 150px;
// Instead of left: 0; you can use right: 0 if the main menu is
// on the very right side of the page.
// Dont forget to adjust the "nav ul ul ul" selector as well
position: absolute;
top: 150%;
left: 0;
transition: all .3s;
// Change to higher transition value to increase effect
}
// Activate submenu when hovering
nav ul li:hover > ul {
top: 100%;
visibility: visible;
opacity: 1;
}
// Position all sub-sub-menus beside the parent sub-menu
nav ul ul ul {
left: 100%;
}
nav ul ul li:hover > ul {
top: 0;
}
// ===== ADDITIONAL STYLING FOR CODEPEN =====
nav {
max-width: 1000px;
margin: 25px auto;
}
// ===== ANSERWS TO SOME QUESTIONS =====
/*
* Why not use classes?
To keep the specificity as low as possible and therefore make this code easy to extend. Therefore I used the "nav" element selctor as basis for all selectors to just affect the styling of nav menus.
* How to add "Submenu arrows" to visualize that there is a submenu?
This can only be handeled via classes. Add something like "has-submenu" to the li that has a submenu.
I only wanted to use element selectors in this example to keep the specificity low.
*/
Also see: Tab Triggers