Question

我正在使用教程构建一个菜单，我通过添加下拉子菜单来扩展它，当你将鼠标悬停在主菜单的项目上时，但是当我将鼠标悬停在菜单项上时，而不仅仅是那个子菜单下降，所有子菜单都下降（但显示为空）。

请参阅以下内容：

<body>

    <div class="header">
             <h1>Basics of Web Design</h1>

            <div class="nav"> 
                <a href="#" class="hamburger">
                    <div class="line"></div>
                    <div class="line"></div>
                    <div class="line"></div>
                </a>
                <ul class="clearfix menu">
                    <li><a href="#">Home</a></li>
                    <li><a href="#">HTML</a>
                        <ul class="submenu">
                            <li><a href="#">Introduction</a></li>
                            <li><a href="#">sub heading 2</a></li>
                            <li><a href="#">sub heading 3</a></li>
                            <li><a href="#">sub heading 4</a></li>
                            <li><a href="#">sub heading 5</a></li>
                            <li><a href="#">sub heading 6</a></li>
                        </ul>
                    </li>
                    <li><a href="#">CSS</a>
                        <ul class="submenu">
                            <li><a href="#">Introduction</a></li>
                            <li><a href="#">sub heading 2</a></li>
                            <li><a href="#">sub heading 3</a></li>
                        </ul>
                    </li>
                    <li><a href="#">JavScript</a>

                    </li>
                    <li><a href="#">Aesthetics</a>

                    </li>
                </ul>
            </div>
        </div>

    </body>
    </html>

CSS：

/* resets everything */
*, *:before, *:after {
    margin: 0;
    padding: 0;
    box-sizing: border-box
}
.clearfix:after {
    content: "";
    display: table;
    clear: both;
}
html, body {
    height: 100%;
    background-image: url(../images/bg-tile.png);
    background-repeat: repeat;
}
body {
    font: 1em'Roboto', sans-serif;
    color: #555;
    background-color: #fff;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
ul {
    list-style: none;
    max-width: 900px;
    margin: 0 auto;
    border-left: 1px solid #ddd;
    border-right: 1px solid #ddd;
    background: inherit;
}

h1 {
    padding: 30px 0;
    font: 1.5em'Open Sans', sans-serif;
    text-align: center;
}
.nav {
    height: 3.6em;
    border-top: 1px solid #ddd;
    border-bottom: 1px solid #ddd;
    background-color: #f5f5f5;
    /* adds box shadow */
    -webkit-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    -moz-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
}

ul a {
    display: block;
    padding: 20px;
    padding-right: 0 !important;
    /* important overrides media queries */
    font-size: 13px;
    font-weight: bold;
    text-align: center;
    color: #aaa;
    cursor: pointer;
    text-decoration: none;
}
ul a:hover {
    background: #eee;
}
.nav li {
    float: left;
    width: 20%;
    border-right: 1px solid #ddd;
    position: relative;
}
.nav li > ul li{
    float: left;
    position: relative;
}
.nav li:last-child {
    border-right: none;
}
ul.submenu {
    display: none;
}
ul.submenu li {
    width: 100%;
    border-right: none;
}
ul.submenu li a {
    width: 100%;
    padding: 6px;
}
ul.menu > li:hover ul.submenu {
    float: none;
    display: block;
}
@media only screen and (max-width: 600px) {
    .hamburger {
        padding: 15px;
        display: block;
    }
    .line {
        border-bottom: 4px solid #bbb;
        width: 35px;
        margin-bottom: 6px;
    }
    .line:last-child {
        margin-bottom: 0;
    }
    .nav li {
        width: 100%;
    }
    .menu {
        height: 0;
        overflow: hidden;
        transition: height 0.3s linear;
        -webkit-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
        -moz-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
        box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    }
    .slide-down {
        height: 275px;
    }
}

Js for resposive menu：

$('.hamburger').on('click', function(e) {
  // Prevent link from jumping to the top of the page
  e.preventDefault();
  // If menu is already showing, slide it up. Otherwise, slide it down.
  $('.menu').toggleClass('slide-down');
});

Answer 1

在你的CSS中制作这些chage并希望它能够发挥作用。

/* resets everything */
*, *:before, *:after {
    margin: 0;
    padding: 0;
    box-sizing: border-box
}
.clearfix:after {
    content: "";
    display: table;
    clear: both;
}
html, body {
    height: 100%;
    background-image: url(../images/bg-tile.png);
    background-repeat: repeat;
}
body {
    font: 1em'Roboto', sans-serif;
    color: #555;
    background-color: #fff;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
ul {
    list-style: none;
    max-width: 900px;
    margin: 0 auto;
    /*border-left: 1px solid #ddd;
    border-right: 1px solid #ddd;
    background: inharit;*/
}

h1 {
    padding: 30px 0;
    font: 1.5em'Open Sans', sans-serif;
    text-align: center;
}
.nav {
    height: 3.6em;
    border-top: 1px solid #ddd;
    border-bottom: 1px solid #ddd;
    background-color: #f5f5f5;
    /* adds box shadow */
    -webkit-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    -moz-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
}

ul a {
    display: block;
    padding: 20px;
    padding-right: 0 !important;
    /* important overrides media queries */
    font-size: 13px;
    font-weight: bold;
    text-align: center;
    color: #aaa;
    cursor: pointer;
    text-decoration: none;
}
ul a:hover {
    background: #eee;
}
.nav li {
    float: left;
    width: 20%;
    border-right: 1px solid #ddd;
    position: relative;
}
.nav li > ul li{
    float: left;
    position: relative;
}
.nav li:last-child {
    border-right: none;
}
ul.submenu {
    display: none;
}
ul.submenu li {
    width: 100%;
    border-right: none;
    background: #eee;
}
ul.submenu li a {
    width: 100%;
    padding: 6px;
}
ul.menu > li:hover ul.submenu {
    float: none;
    display: block;
    background: #eee;
}
@media only screen and (max-width: 600px) {
    .hamburger {
        padding: 15px;
        display: block;
    }
    .line {
        border-bottom: 4px solid #bbb;
        width: 35px;
        margin-bottom: 6px;
    }
    .line:last-child {
        margin-bottom: 0;
    }
    .nav li {
        width: 100%;
    }
    .menu {
        height: 0;
        overflow: hidden;
        transition: height 0.3s linear;
        -webkit-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
        -moz-box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
        box-shadow: -1px 3px 5px 0px rgba(52, 44, 77, 1);
    }
    .slide-down {
        height: 275px;
    }
}

如何使用css显示一个子菜单

1 个答案: