我对构建 html/css 网站相当陌生，但我已经构建了一个带有悬停效果导航的模板。在台式机或平板电脑上查看时效果很好。在移动设备上，我有一个汉堡菜单图标，单击该图标时会显示一个垂直列表的菜单。顶级菜单名称显示正常，但是当将鼠标悬停在它们上方以显示子菜单项时，我无法正确获取代码，因此每个顶级菜单名称之间的空间会扩展以适合其间的子菜单垂直列表。它似乎覆盖在顶级菜单上（请参阅我所附的屏幕截图）。移动视图屏幕截图
我一直无法解决这个问题，因此我们将不胜感激地收到任何帮助指示。 我已经包含了下面的 HTML 和 CSS，所以对于长度表示歉意。
index.html
<body>
<!-- Header Section Start -->
<section class="header">
<!-- Navigation Bar Start -->
<nav>
<!-- Website Logo Image Inside Navigation Bar -->
<a href="index.html"><img src="images/logo/world-war-2-logo.webp" alt="World-War-2.org Logo" title="World-War-2.org"> </a>
<!-- Menu Links in Navigation Bar -->
<div class="nav-menu-links" id="navmenulinks">
<!-- Responsive Menu Open Button in Navigation Bar -->
<img class="nav-menu open" src="images/icons/menu/close.webp" onclick="hidemenu()" alt="World-War-2.org menu opened">
<ul>
<li><a class="main-menu-item" href="index.html">Home</a></li>
<li><a class="main-menu-item" href="#">The Road to War</a></li>
<li><a class="main-menu-item-with-submenu" href="#">Eastern Europe</a>
<div class="sub-menu-1">
<ul>
<li><a class="sub-menu-1-item" href="#">Invasion of Poland</a></li>
<li><a class="sub-menu-1-item" href="#">Winter War</a></li>
<li><a class="sub-menu-1-item" href="#">Barbarossa</a></li>
<li><a class="sub-menu-1-item" href="#">Typhoon</a></li>
</ul>
</div>
</li>
<li><a class="main-menu-item-with-submenu" href="#">Western Europe</a>
<div class="sub-menu-1">
<ul>
<li><a class="sub-menu-1-item" href="#">Phoney War</a></li>
<li><a class="sub-menu-1-item" href="#">Denmark and Norway</a></li>
<li><a class="sub-menu-1-item" href="#">Low Countries</a></li>
<li><a class="sub-menu-1-item" href="#">Battle of France</a></li>
</ul>
</div>
</li>
<li><a class="main-menu-item-with-submenu" href="#">Italy and the Balkans</a>
<div class="sub-menu-1">
<ul>
<li><a class="sub-menu-1-item" href="#">Greece Attacked</a></li>
<li><a class="sub-menu-1-item" href="#">Invasion of Yugloslavia</a></li>
<li><a class="sub-menu-1-item" href="#">Greece Overcome</a></li>
</ul>
</div>
</li>
<li><a class="main-menu-item-with-submenu" href="#">North Africa</a>
<div class="sub-menu-1">
<ul>
<li><a class="sub-menu-1-item" href="#">Italy Advances</a></li>
<li><a class="sub-menu-1-item" href="#">British Reposte</a></li>
<li><a class="sub-menu-1-item" href="#">Enter Rommel</a></li>
</ul>
</div>
</li>
<li><a class="main-menu-item-with-submenu" href="#">Battle of the Atlantic</a>
<div class="sub-menu-1">
<ul>
<li><a class="sub-menu-1-item" href="#">Bottled Up</a></li>
<li><a class="sub-menu-1-item" href="#">1st Happy Time</a></li>
<li><a class="sub-menu-1-item" href="#">2nd Happy Time</a></li>
</ul>
</div>
</li>
</ul>
</div>
<!-- Responsive Menu Close Button in Navigation Bar -->
<img class="nav-menu close" src="images/icons/menu/menu.webp" onclick="showmenu()" alt="World-War-2.org menu closed">
</nav>
<!-- Navigation Bar End -->
CSS
* {
margin: 0;
padding: 0;
font-family: "Alumni Sans", sans-serif;
}
/* Header Section */
.header {
min-height: 100vh;
width: 100%;
background-image: linear-gradient(rgba(0,0,0,0.25),#999393),url(images/hero-photo/a-world-at-war-cover-d-1040-l85.webp);
background-position: center;
background-size: cover;
position: relative;
}
/* Navigation Bar */
nav {
display: flex;
padding: 1% 3%;
justify-content: space-between;
align-items: center;
}
/* Website Logo Image Inside Navigation Bar */
nav img{
width: 175px;
}
.nav-menu-links{
flex: 1;
text-align: right;
}
.nav-menu-links ul li{
list-style: none;
display: inline-block;
padding: 8px 12px;
position:relative;
}
.nav-menu-links ul li a {
color: #fff;
text-decoration: none;
font-family: "Amatic SC", sans-serif;
font-size: 20px;
font-style: normal;
font-weight: 700;
}
.nav-menu-links ul li::after{
content: '';
width: 0%;
height: 2px;
background: #f44336;
display: block;
margin: auto;
transition: 0.5s;
}
.nav-menu-links ul li:hover::after{
width: 100%;
}
/* Hide Sub Menu being displayed until Hovered on */
.sub-menu-1{
display: none;
}
/* Display Sub Menu when Hovered on */
.nav-menu-links ul li:hover .sub-menu-1 {
display: block;
position: absolute;
margin-top: 5px;
margin-left: -15px;
width: fit-content;
}
/* Sub Menu1 UL */
.nav-menu-links ul li:hover .sub-menu-1 ul {
margin: 10px;
background: rgba(0,0,0,0.25);
text-align: left;
}
.nav-menu-links ul li:hover .sub-menu-1 ul li {
padding: 10px;
transition: 0.5s;
border-bottom: 1px dashed #fff;
width: fit-content;
white-space: nowrap;
position: relative
}
.nav-menu-links ul li:hover .sub-menu-1 ul li:last-child {
border-bottom: none;
}
.text-box {
width: 90%;
color: #fff;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%,-50%);
text-align: center;
}
.text-box h1 {
font-size: 75px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.text-box p {
margin: 10px 0 40px;
font-size: 40px;
color: #fff;
font-family: "Amatic SC", sans-serif;
font-weight: 400;
}
.hero-buttons a{
font-size: 20px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.hero-button1{
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: transparent;
position: relative;
cursor: pointer;
}
.hero-button1:hover {
border: 1px solid #fff;
background: #f44336;
transition: 0.5s;
}
.hero-button2 {
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: #f44336;
position: relative;
cursor: pointer;
}
.hero-button2:hover {
border: 1px solid #f44336;
background: #f44336;
transition: 0.5s;
}
.hero-button3 {
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: transparent;
position: relative;
cursor: pointer;
}
.hero-button3:hover {
border: 1px solid #fff;
background: #f44336;
transition: 0.5s;
}
.quote-text-box {
width: 90%;
color: #fff;
position: absolute;
top: 85%;
left: 50%;
transform: translate(-50%,-50%);
text-align: center;
}
.quote-text-box h1 {
font-size: 25px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.quote-text-box p {
margin: 10px 0 10px;
font-size: 20px;
color: #fff;
font-family: "Amatic SC", sans-serif;
font-weight: 400;
}
.introduction{
background: #fff;
width: auto;
padding: 5px 5px 5px 5px;
}
.introduction h1 {
font-size: 20px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
text-align: center;
text-decoration: underline;
}
.introduction p {
font-size: 17px;
color: #000000;
font-family: "Alumni Sans", sans-serif;
font-weight: 400;
text-align: justify;
padding: 5px 5px 5px 5px;
line-height: 24px;
}
.introduction p::first-letter {
font-size: 25px;
font-weight: 400;
}
.bold {
font-weight: 700;
font-size: 17px;
font-family: "Alumni Sans", sans-serif;
}
.red {
font-weight: 400;
color: #f44336;
font-size: 17px;
font-family: "Alumni Sans", sans-serif;
}
.flags {
width: auto;
padding: 5px 0px 5px 0px;
}
.flags-row {
align-items: center;
justify-content: center;
display: flex;
flex-wrap: wrap;
padding: 5px 0px 5px 0px;
}
.flags-column {
box-sizing: border-box;
padding: 0px 5px 0px 5px;
}
.flags-column img {
border: 1px solid #808080;
border-radius: 5px;
}
.medals {
width: auto;
padding: 5px 5px 5px 5px;
}
.medals-row {
display: flex;
align-items: center;
justify-content: space-around;
}
.medals-column{
box-sizing: border-box;
}
.copyright {
background: #808080;
width: auto;
padding: 5px 5px 5px 5px;
margin: auto;
}
.copyright p {
font-size: 17px;
color: #fff;
font-family: "Alumni Sans", sans-serif;
font-weight: 400;
text-align: center;
}
/* Viewport of 700px Max */
@media(max-width: 700px) {
/* Website Logo Image Inside Navigation Bar */
nav img {
width: 125px;
}
.text-box h1 {
font-size: 40px;
}
.text-box p {
font-size: 25px;
}
.nav-menu-links {
position: absolute;
background: rgba(0,0,0,0.75);
height: 100vh;
width: 100%;
top: 0;
right: -100%;
text-align: left;
z-index: 2;
transition: 1s;
white-space: nowrap;
background-color: red;
}
.nav-menu-links ul {
padding: 30px;
}
.nav-menu-links ul li{
display: flex;
}
.nav-menu {
margin: 10px;
cursor: pointer;
width: auto;
}
/* Start Sub Menu Expands down */
.main-menu-item {
}
.main-menu-item {
}
.main-menu-item-with-submenu {
}
.sub-menu-1 {
height: auto;
}
.sub-menu-1-item {
list-style-type: none;
}
/* End Sub Menu Expands down */
.hero-button1 {
width: 100px;
}
.hero-button2 {
width: 100px;
}
.hero-button3 {
width: 100px;
}
.flags-column img {
width: 48px;
height: 29px;
}
.medals-column img{
width: 45px;
height: 88px;
}
}
/* Viewport greater than 701px, but less that 1024px */
@media(min-width: 701px) {
.text-box h1 {
font-size: 55px;
}
.text-box p {
font-size: 32px;
}
/* Hamburger and X buttons hide */
.nav-menu {
display: none;
}
.hero-button1 {
width: 125px;
}
.hero-button2 {
width: 125px;
}
.hero-button3 {
width: 125px;
}
.flags-column img {
width: 60px;
height: 36px;
}
.medals-column img {
width: 80px;
height: 156px;
}
}
/* Viewport greater than 1024px */
@media(min-width: 1024px) {
.text-box h1 {
font-size: 75px;
}
.text-box p {
font-size: 40px;
}
/* Hamburger and X buttons hide */
.nav-menu {
display: none;
}
.hero-button1 {
width: 150px;
}
.hero-button2 {
width: 150px;
}
.hero-button3 {
width: 150px;
}
.flags-column img {
width: 80px;
height: 48px;
}
.medals-column img {
width: 120px;
height: 234px;
}
}
当我将鼠标悬停在顶级菜单上时，我希望每个菜单之间的空间能够展开并由子菜单填充。 （希望这是有道理的）。
为了使子菜单适合父菜单之间，最主要的是删除它们的绝对位置。因此，我在 @media(max-width: 700px) 中添加了一些代码（我只是重点关注这一点，只是为了向您展示如何做到这一点），主要是子菜单上的position:relative。我还在导航中添加了隐藏的overflow-x，以免div.nav-menu-links在右侧溢出。您也不需要 showmenu 和 hidemenu 这两个函数，只需要一个可以切换 .show 类的函数。你仍然可以更多地清理你的代码，为什么不在安装子菜单时添加过渡（这样你就不能使用显示无，你将不得不用高度来做到这一点）。
var navmenulinks = document.getElementById("navmenulinks");
console.log(navmenulinks)
function showmenu() { navmenulinks.classList.toggle('show') }* {
margin: 0;
padding: 0;
font-family: "Alumni Sans", sans-serif;
}
/* Header Section */
.header {
height: 100vh;
width: 100%;
background-image: linear-gradient(rgba(0,0,0,0.25),#999393),url(images/hero-photo/a-world-at-war-cover-d-1040-l85.webp);
background-position: center;
background-size: cover;
overflow-x: hidden; /*-----added this overflow hidden-------------*/
position: relative;
}
/* Navigation Bar */
nav {
display: flex;
padding: 1% 3%;
justify-content: space-between;
align-items: center;
}
/* Website Logo Image Inside Navigation Bar */
nav img{
width: 175px;
}
.nav-menu-links{
flex: 1;
text-align: right;
}
.nav-menu-links ul li{
list-style: none;
display: inline-block;
padding: 8px 12px;
position:relative;
}
.nav-menu-links ul li a {
color: #fff;
text-decoration: none;
font-family: "Amatic SC", sans-serif;
font-size: 20px;
font-style: normal;
font-weight: 700;
}
.nav-menu-links ul li::after{
content: '';
width: 0%;
height: 2px;
background: #f44336;
display: block;
margin: auto;
transition: 0.5s;
}
.nav-menu-links ul li:hover::after{
width: 100%;
}
/* Hide Sub Menu being displayed until Hovered on */
.sub-menu-1{
display: none;
}
/* Display Sub Menu when Hovered on */
.nav-menu-links ul li:hover .sub-menu-1 {
display: block;
position: absolute;
margin-top: 5px;
margin-left: -15px;
width: fit-content;
}
/* Sub Menu1 UL */
.nav-menu-links ul li:hover .sub-menu-1 ul {
margin: 10px;
background: rgba(0,0,0,0.25);
text-align: left;
}
.nav-menu-links ul li:hover .sub-menu-1 ul li {
padding: 10px;
transition: 0.5s;
border-bottom: 1px dashed #fff;
width: fit-content;
white-space: nowrap;
position: relative
}
.nav-menu-links ul li:hover .sub-menu-1 ul li:last-child {
border-bottom: none;
}
.text-box {
width: 90%;
color: #fff;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%,-50%);
text-align: center;
}
.text-box h1 {
font-size: 75px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.text-box p {
margin: 10px 0 40px;
font-size: 40px;
color: #fff;
font-family: "Amatic SC", sans-serif;
font-weight: 400;
}
.hero-buttons a{
font-size: 20px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.hero-button1{
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: transparent;
position: relative;
cursor: pointer;
}
.hero-button1:hover {
border: 1px solid #fff;
background: #f44336;
transition: 0.5s;
}
.hero-button2 {
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: #f44336;
position: relative;
cursor: pointer;
}
.hero-button2:hover {
border: 1px solid #f44336;
background: #f44336;
transition: 0.5s;
}
.hero-button3 {
width: 150px;
display: inline-block;
text-decoration: none;
color: #fff;
border: 1px solid #fff;
padding: 12px 0px;
margin: 0 3px;
font-size: 13px;
background: transparent;
position: relative;
cursor: pointer;
}
.hero-button3:hover {
border: 1px solid #fff;
background: #f44336;
transition: 0.5s;
}
.quote-text-box {
width: 90%;
color: #fff;
position: absolute;
top: 85%;
left: 50%;
transform: translate(-50%,-50%);
text-align: center;
}
.quote-text-box h1 {
font-size: 25px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
}
.quote-text-box p {
margin: 10px 0 10px;
font-size: 20px;
color: #fff;
font-family: "Amatic SC", sans-serif;
font-weight: 400;
}
.introduction{
background: #fff;
width: auto;
padding: 5px 5px 5px 5px;
}
.introduction h1 {
font-size: 20px;
font-family: "Amatic SC", sans-serif;
font-weight: 700;
text-align: center;
text-decoration: underline;
}
.introduction p {
font-size: 17px;
color: #000000;
font-family: "Alumni Sans", sans-serif;
font-weight: 400;
text-align: justify;
padding: 5px 5px 5px 5px;
line-height: 24px;
}
.introduction p::first-letter {
font-size: 25px;
font-weight: 400;
}
.bold {
font-weight: 700;
font-size: 17px;
font-family: "Alumni Sans", sans-serif;
}
.red {
font-weight: 400;
color: #f44336;
font-size: 17px;
font-family: "Alumni Sans", sans-serif;
}
.flags {
width: auto;
padding: 5px 0px 5px 0px;
}
.flags-row {
align-items: center;
justify-content: center;
display: flex;
flex-wrap: wrap;
padding: 5px 0px 5px 0px;
}
.flags-column {
box-sizing: border-box;
padding: 0px 5px 0px 5px;
}
.flags-column img {
border: 1px solid #808080;
border-radius: 5px;
}
.medals {
width: auto;
padding: 5px 5px 5px 5px;
}
.medals-row {
display: flex;
align-items: center;
justify-content: space-around;
}
.medals-column{
box-sizing: border-box;
}
.copyright {
background: #808080;
width: auto;
padding: 5px 5px 5px 5px;
margin: auto;
}
.copyright p {
font-size: 17px;
color: #fff;
font-family: "Alumni Sans", sans-serif;
font-weight: 400;
text-align: center;
}
/* Viewport of 700px Max */
@media(max-width: 700px) {
/* Website Logo Image Inside Navigation Bar */
/*-----------------this the beginning of added part------------------------*/
.nav-menu-links ul li .sub-menu-1{
position: relative;
margin-top: 5px;
margin-left: -15px;
width: fit-content;
}
.nav-menu-links ul li:hover .sub-menu-1 {
position: relative;
display: block;
width: fit-content;
}
.nav-menu-links ul li{
display: flex;
flex-direction: column;
}
/*---------------------------------end of added part----------------------------------*/
nav img {
width: 125px;
}
.text-box h1 {
font-size: 40px;
}
.text-box p {
font-size: 25px;
}
.nav-menu-links {
position: absolute;
background: rgba(0,0,0,0.75);
min-height: 100vh; /*----------added this -----------*/
height: fit-content; /*----------added this -----------*/
width: 100%;
top: 0;
right: -100%;
text-align: left;
z-index: 2;
transition: 1s;
white-space: nowrap;
background-color: red;
}
.nav-menu-links ul {
padding: 30px;
}
.nav-menu-links ul li{
display: flex;
}
.nav-menu {
margin: 10px;
cursor: pointer;
width: auto;
}
/* Start Sub Menu Expands down */
.main-menu-item {
}
.main-menu-item {
}
.main-menu-item-with-submenu {
}
.sub-menu-1 {
height: auto;
}
.sub-menu-1-item {
list-style-type: none;
}
/* End Sub Menu Expands down */
.hero-button1 {
width: 100px;
}
.hero-button2 {
width: 100px;
}
.hero-button3 {
width: 100px;
}
.flags-column img {
width: 48px;
height: 29px;
}
.medals-column img{
width: 45px;
height: 88px;
}
}
/* Viewport greater than 701px, but less that 1024px */
@media(min-width: 701px) {
.text-box h1 {
font-size: 55px;
}
.text-box p {
font-size: 32px;
}
/* Hamburger and X buttons hide */
.nav-menu {
display: none;
}
.hero-button1 {
width: 125px;
}
.hero-button2 {
width: 125px;
}
.hero-button3 {
width: 125px;
}
.flags-column img {
width: 60px;
height: 36px;
}
.medals-column img {
width: 80px;
height: 156px;
}
}
/* Viewport greater than 1024px */
@media(min-width: 1024px) {
.text-box h1 {
font-size: 75px;
}
.text-box p {
font-size: 40px;
}
/* Hamburger and X buttons hide */
.nav-menu {
display: none;
}
.hero-button1 {
width: 150px;
}
.hero-button2 {
width: 150px;
}
.hero-button3 {
width: 150px;
}
.flags-column img {
width: 80px;
height: 48px;
}
.medals-column img {
width: 120px;
height: 234px;
}
}
/*----------------------added class for toggle---------------------------*/
.nav-menu-links.show{
right: 0%;
}<section class="header">
<!-- Navigation Bar Start -->
<nav>
<!-- Website Logo Image Inside Navigation Bar -->
<a href="index.html"><img src="images/logo/world-war-2-logo.webp" alt="World-War-2.org Logo" title="World-War-2.org"> </a>
<!-- Menu Links in Navigation Bar -->
<div class="nav-menu-links" id="navmenulinks">
<!-- Responsive Menu Open Button in Navigation Bar -->
<img class="nav-menu open" src="images/icons/menu/close.webp" onclick="showmenu()" alt="World-War-2.org menu opened">
<ul>
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