JSFiddle - React, Tailwind, and code Playground

HTML

<div class="menu-container">
    <ul class="menu clearfix">
        <li><a href="#">Item 1</a>
            <!-- Nível 1 -->
            <!-- submenu -->
            <ul class="sub-menu clearfix">
                <li><a href="#">Sub 1</a>
                    <!-- Nível 2 -->
                    <!-- submenu do submenu -->
                    <ul class="sub-menu">
                        <li><a href="#">Sub Sub 1</a>
                            <!-- Nível 3 -->
                            <!-- submenu do submenu do submenu -->
                            <ul class="sub-menu">
                                <li><a href="#">Sub Sub Sub 1</a>
                                <li><a href="#">Sub Sub Sub 2</a>
                                </li>
                            </ul><!-- submenu do submenu do submenu -->
                        </li>
                        <li><a href="#">Sub Sub 2</a></li>
                       
                    </ul><!-- submenu do submenu -->
                </li>
                <li><a href="#">Sub 2</a></li>
               
            </ul><!-- submenu -->
        </li>
        <li><a href="#">Item 2</a></li>
       
    </ul>
</div>

CSS

body, 
.menu,
.sub-menu {
    margin: 0;
    padding: 0;
}
.clearfix:after{
    content: '.';
    display: block;
    clear: both;
    height: 0;
    line-height: 0;
    font-size: 0;
    visibility: hidden;
    overflow: hidden;
}
.menu,
.sub-menu {
    list-style: none;
    background: #000;
}
.sub-menu {
    background: #444;
}
.menu a {
    text-decoration: none;
    display: block;
    padding: 10px;
    color: #fff;
    font-family: sans-serif;
    font-size: 14px;
    text-transform: uppercase;
    font-weight: 700;
}
.menu li {
    position: relative;
}
.menu > li {
    float: left;
}
.menu > li:hover {
    background: #444;
}
.menu li:hover > .sub-menu {
    display: block;
}
.sub-menu {
    display: none;
    position: absolute;
    min-width: 150px;
}
.sub-menu li:hover {
    background: #555;
}
.sub-menu .sub-menu {
    top: 0;
    left: 100%;
}