我的 CSS 菜单有这个 html:

<nav class="clearfix">
    <ul class="clearix">
        <li><a href="http://www.domain.co.uk/">Homepage</a></li>
        <li><a href="/services">Services</a></li>
        <li><a href="/project-gallery">Project Gallery</a></li>
        <li><a href="/contact-us">Contact Us</a></li>  
    </ul>
    <a href="#" id="pull">Menu</a>  
</nav>

nav {
    height: 50px;  
    width: 100%;  
    background: #F00;  
    font-size: 14pt;  
    font-family: Arial;
    position: relative;  
    border-bottom: 5px solid #FFFFFF;  
}  
nav ul {  
    padding: 0;  
    margin: 0 auto;  
    width: 100%;  
    height: 50px;
    text-align: center;
}
nav li {  
    display: inline;
}  
.clearfix:before,  
.clearfix:after {  
    content: " ";  
    display: table;  
}  
.clearfix:after {  
    clear: both;  
}  
.clearfix {  
    *zoom: 1;  
}  
nav a {  
    color: #FFFFFF;  
    display: inline-block;  
    width: auto;

    text-align: center;  
    text-decoration: none;  
    line-height: 50px;  
}  
nav li a {
    box-sizing:border-box;  
    -moz-box-sizing:border-box;  
    -webkit-box-sizing:border-box;
    padding-left: 10px;
    padding-right: 10px;
}  
nav li:last-child a {  
    border-right: 0;  
}  
nav a:hover, nav a:active {  
    background-color: #000000;
    color:#FFFFFF;  
} 
nav a#pull {  
    display: none;  
}  
@media screen and (max-width: 600px) {  
    nav {   
        height: auto;  
    }  
    nav ul {  
        width: 100%;  
        display: block;  
        height: auto;  
    }  
    nav li {  
        width: 50%;  
        float: left;  
        position: relative;  
    }  
    nav li a {  
        border-bottom: 1px solid #FFFFFF;  
        border-right: 1px solid #FFFFFF;  
    }  
    nav a {  
        text-align: left;  
        width: 100%;  
        text-indent: 25px;  
    }  
}  
@media only screen and (max-width : 480px) {  
    nav {  
        border-bottom: 0;  
    }  
    nav ul {  
        display: none;  
        height: auto;  
    }  
    nav a#pull {  
        display: block;
        color:#FFFFFF;
        background-color: #F00;  
        width: 100%;  
        position: relative;  
    }  
    nav a#pull:after {  
        content:"";  
        background: url('nav-icon.png') no-repeat;  
        width: 30px;  
        height: 30px;  
        display: inline-block;  
        position: absolute;  
        rightright: 15px;  
        top: 10px;  
    }  
}  
@media only screen and (max-width : 320px) {  
    nav li {  
        display: block;  
        float: none;  
        width: 100%;  
    }  
    nav li a {  
        border-bottom: 1px solid #FFFFFF;  
    }  
}  

我正在寻找一种方法来添加子菜单，然后在第一个子菜单上添加第二个子菜单，但仍然保持它的响应速度。

我该怎么做？

http://jsfiddle.net/EYjnG/

最佳答案

JSFIDDLE DEMO 逻辑很简单，有这段代码

#submenu,#submenu2,#submenu3{
    visibility:hidden;       /*turn all the submenus visibility hidden */
}
#top_menu li.first:hover #submenu,#submenu li.second:hover #submenu2,#submenu2     li.second:hover #submenu3{
    visibility:visible;      /*On hover turn on visibility visible */
}      

完整代码:

HTML:

<div id="top_menu">  <!--MAIN MENU -->                      
    <ul>
        <li class="first">menu1                 
            <div id="submenu">   <!--First Submenu -->
                <ul class="abc">
                    <li class="second">item1    
                        <div id="submenu2">  <!--Second Submenu -->
                            <ul class="abc">
                                <li class="second">item1_1
                                    <div id="submenu3">  <!--Third Submenu -->
                                        <ul class="abc">
                                            <li class="second">item1_1_1</li>
                                            <li class="second">item1_1_2</li>
                                            <li class="second">item1_1_3</li>
                                        </ul>
                                    </div>  <!--third Submenu Ends here-->
                                </li>
                                <li class="second">item1_2</li>
                                <li class="second">item1_3</li>
                            </ul>
                        </div>  <!--Second Submenu Ends here-->                         
                    </li>
                    <li class="second">item2
                                <div id="submenu2">
                                    <ul class="abc">
                                        <li class="second">item2_1</li>
                                        <li class="second">item2_2</li>
                                        <li class="second">item2_3</li>
                                    </ul>
                                </div>                              
                    </li>
                    <li class="second">item3
                                <div id="submenu2">
                                    <ul class="abc">
                                        <li class="second">item3_1</li>
                                        <li class="second">item3_2</li>
                                        <li class="second">item3_3</li>
                                    </ul>
                                </div>                              
                    </li>
                </ul>
            </div>
        </li>   

        <li class="first">menu2
            <div id="submenu">
                <ul class="abc">
                    <li class="second">item1</li>
                    <li class="second">item2</li>
                    <li class="second">item3</li>
                    <li class="second">item4</li>
                </ul>
            </div>
        </li>

    </ul>   
</div>

CSS:

ul{
    padding:10px;
    padding-right:0px;
}
li.first{
    display:block;
    display:inline-block;
    padding:5px;
    padding-right:25px;
    padding-left:25px;
    cursor:pointer;
}
li.second{
    list-style:none;
    margin:0px;
    padding:5px;
    padding-right:25px;
    margin-bottom:5px;
    cursor:pointer;
}
#submenu li.second:hover{
    background:red;
    border-radius:5px;
}

#submenu2 li.second:hover{
    background:green;
    border-radius:5px;
}
/*********MAIN LOGIC***************/

#submenu,#submenu2,#submenu3{
    visibility:hidden;
}
#top_menu li.first:hover #submenu,#submenu li.second:hover #submenu2,#submenu2 li.second:hover #submenu3{
    visibility:visible;
}
/**********STYLING SUBMENUS**************/
#submenu{
    padding-right:0px;
    text-align:left;
    position:absolute;
    background:white;
    box-shadow:0px 0px 5px;
    border-radius:5px;
}
#submenu2{
    text-align:left;
    position:absolute;
    left:70px;
    top:0px;
    background:red;
    box-shadow:0px 0px 5px;
    border-radius:5px;
}
#submenu3{
    text-align:left;
    position:absolute;
    left:80px;
    top:0px;
    background:green;
    box-shadow:0px 0px 5px;
    border-radius:5px;
}

只要理解这段代码背后的逻辑，你就可以制作任意数量的子菜单。

关于html - 如何在响应式 CSS 菜单上添加子菜单，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19439212/