CSSالقوائم المنسدلة

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

.dropdown-btn {
    background-color: #0d6efd;
    color: white;
    padding: 12px 18px;
    font-size: 16px;
    border: none;
    cursor: pointer;
}

/* جعلنا القائمة بالأساس مخفية */
.dropdown-content {
    display: none;
    position: absolute;
    background-color: #fff;
    min-width: 160px;
    box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
    z-index: 1;
}

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

/* عند تمرير الماوس فوق أي جزء في القائمة سيتم إظهارها */
.dropdown:hover .dropdown-content {
    display: block;
}

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

.dropdown:hover .dropdown-btn {
    background-color: #0b5ed7;
}
</style>

<div class="dropdown">
    <button class="dropdown-btn">Dropdown</button>
    <div class="dropdown-content">
        <a href="#">Link 1</a>
        <a href="#">Link 2</a>
        <a href="#">Link 3</a>
    </div>
</div>

.dropdown-content {
    right: 0;
}

<div class="dropdown">
    <img class="dropdown-img" src="bird.jpg"/>
    <div class="dropdown-content">
        <img src="bird.jpg"/>
        <p>A beautiful bird.</p>
    </div>
</div>

<ul>
    <li><a href="#">Home</a></li>
    <li><a href="#">News</a></li>
    <li class="dropdown">
        <a href="javascript:void(0)" class="drop-btn">Submenu</a>
        <div class="dropdown-content">
            <a href="#">Link 3</a>
            <a href="#">Link 4</a>
            <a href="#">Link 5</a>
        </div>
    </li>
</ul>

<style>
nav {
    background-color: #333;
    font-family: arial;
    font-size: 14px;
}

nav ul {
    padding: 0;
    margin: 0;
    list-style: none;
    position: relative;
}

nav ul li {
    display: inline-block;
    background-color: #333;
}

nav a {
    display: block;
    padding: 0 15px;
    color: white;
    line-height: 45px;
    text-decoration: none;
}

nav a:hover { 
    background-color: cadetblue; 
}

nav ul ul {
    display: none;
    position: absolute;
    top: 45px;     
}

nav ul li:hover > ul {
    display: inherit;
}

nav ul li:hover > a {
    background-color: cadetblue; 
}

nav ul ul li {
    width: 150px;
    float: none;
    display: list-item;
    position: relative;
    border: 1px solid #555;
}

nav ul ul ul li {
    position: relative;
    top: -45px; 
    left: 150px;
}
</style>

<nav>
    <ul>
        <li><a href="javascript:void(0)">Menu ▾</a>
            <ul>
                <li><a href="#">Link 1</a></li>
                <li><a href="#">Link 2</a></li>
                <li><a "javascript:void(0)">Sub Menu ▸</a>
                    <ul>
                        <li><a href="#">Link 1</a></li>
                        <li><a href="#">Link 2</a></li>
                    </ul>
                </li>
            </ul>
        </li>
        <li><a href="#">Link 1</a></li>
        <li><a href="#">Link 2</a></li>
        <li><a href="#">Link 3</a></li>
    </ul>
</nav>