我正在开展以下项目：
$(function () {
var links = $('.sidebar-links > div');
links.on('click', function () {
links.removeClass('selected');
$(this).addClass('selected');
});
});
function openCity(evt, cityName) {
// Declare all variables
var i, tabcontent, tablinks;
// Get all elements with class="tabcontent" and hide them
tabcontent = document.getElementsByClassName("tabcontent");
for (i = 0; i < tabcontent.length; i++) {
tabcontent[i].style.display = "none";
}
// Get all elements with class="tablinks" and remove the class "active"
tablinks = document.getElementsByClassName("tablinks");
for (i = 0; i < tabcontent.length; i++) {
tablinks[i].className = tablinks[i].className.replace(" active", "");
}
// Show the current tab, and add an "active" class to the link that opened the tab
document.getElementById(cityName).style.display = "block";
evt.currentTarget.className += " active";
}/* The main content */
.main-content {
font-family: Arial, Helvetica, sans-serif;
max-width: 600px;
padding-top: 40px;
margin: 0 0 40px 260px;
}
.tabcontent {
display: none;
}
.tabcontent:target
{
display:block;
}
/* The left-collapsing sidebar */
.sidebar-left-collapse {
font-family: Arial, Helvetica, sans-serif;
position: fixed;
top: 0;
left: 0;
background-color: #292c2f;
width: 180px;
height: 100%;
padding: 20px 0;
}
.sidebar-left-collapse > a {
display: block;
text-decoration: none;
font-family: Cookie, cursive;
width: 122px;
height: 122px;
margin: 0 auto;
text-align: center;
color: #ffffff;
font-size: 44px;
font-weight: normal;
line-height: 2.6;
border-radius: 50%;
background-color: #181a1b;
}
.sidebar-left-collapse .sidebar-links {
margin: 30px auto;
}
.sidebar-links div > a {
display: block;
text-decoration: none;
margin: 0 auto 5px auto;
padding: 10px 0 10px 5px;
background-color: #35393e;
text-align: left;
color: #b3bcc5;
font-size: 12px;
font-weight: bold;
line-height: 2;
border-left-width: 2px;
border-left-style: solid;
}
.sidebar-links div.selected > a{
background-color: #ffffff;
color: #565d63;
line-height: 2.3;
margin: 0;
}
.sidebar-links div > a i.fa {
position: relative;
font-size: 20px;
top: 3px;
width: 40px;
text-align: center;
}
.sidebar-links div ul.sub-links {
max-height: 0;
overflow: hidden;
list-style: none;
padding: 0 0 0 30px;
color: #b3bcc5;
font-size: 12px;
font-weight: bold;
line-height: 24px;
margin: 0;
transition: 0.4s;
}
.sidebar-links div.selected ul.sub-links {
max-height: 150px;
padding: 12px 0 12px 30px;
}
.sidebar-links div .sub-links a {
text-decoration: none;
color: #b3bcc5;
display: block;
text-align: left;
}
/* Link Colors */
.sidebar-links div.link-blue > a {
border-color: #487db2;
}
.sidebar-links div.link-blue > a i.fa {
color: #487db2;
}
.sidebar-links div.link-red > a {
border-color: #da4545;
}
.sidebar-links div.link-red > a i.fa {
color: #da4545;
}
.sidebar-links div.link-yellow > a {
border-color: #d0d237;
}
.sidebar-links div.link-yellow > a i.fa {
color: #d0d237;
}
.sidebar-links div.link-green > a {
border-color: #86be2e;
}
.sidebar-links div.link-green > a i.fa {
color: #86be2e;
}
/* Making the sidebar responsive */
@media (max-width: 900px) {
.main-content{
max-width: none;
padding: 70px 20px;
margin: 0 0 40px;
}
.sidebar-left-collapse {
width: auto;
height: auto;
position: static;
padding: 20px 0 0;
}
.sidebar-left-collapse .sidebar-links {
text-align: center;
margin: 20px auto 0;
}
.sidebar-links div {
display: inline-block;
width: 100px;
}
.sidebar-links div > a {
text-align: center;
margin: 0;
padding: 10px 0;
border-left: none;
border-top-width: 2px;
border-top-style: solid;
}
.sidebar-links div > a i.fa {
display: block;
margin: 0 auto 5px;
}
.sidebar-links div ul.sub-links {
display: none;
}
.sidebar-links div.selected .sub-links {
display: block;
position: absolute;
text-align: center;
width: auto;
left: 0;
right: 0;
}
.sidebar-links div.selected .sub-links li {
display: inline-block;
}
.sidebar-links div.selected .sub-links a {
display: inline-block;
margin-right: 20px;
font-size: 13px;
color: #748290;
}
}
/* Smartphone version */
@media (max-width: 450px) {
.main-content{
padding: 90px 20px;
}
.sidebar-left-collapse {
padding: 20px 0;
}
.sidebar-left-collapse .sidebar-links {
text-align: center;
margin: 20px auto 0;
position: relative;
}
.sidebar-links div {
display: block;
width: 240px;
margin: 0 auto 5px;
}
.sidebar-links div > a {
text-align: left;
padding: 10px 25px;
vertical-align: middle;
border-top: none;
border-left-width: 2px;
border-left-style: solid;
}
.sidebar-links div > a i.fa {
display: inline-block;
font-size: 20px;
width: 20px;
margin: 0 20px 0 0;
}
.sidebar-links div.selected .sub-links {
bottom: -90px;
}
}
/* Removing margins and paddings from the body, so that
the sidebar takes the full height of the page */
body {
margin: 0;
padding: 0;
}<aside class="sidebar-left-collapse">
<a href="#" class="company-logo">Logo</a>
<div class="sidebar-links">
<div class="link-blue selected">
<a href="#">
<i class="fa fa-picture-o"></i>Photography
</a>
<ul class="sub-links">
<li><a href="#portraits" class="tablinks" onclick="openCity(event, 'portraits')">Portraits</a></li>
<li><a href="#add-article" class="tablinks" onclick="openCity(event, 'add-article')">Add an article</a></li>
</ul>
</div>
</div>
</aside>
<div class="main-content">
<div id="portraits" class="tabcontent"> Portraits ...</div>
<div id="add-article" class="tabcontent">
<div class="box">
<p>I want to be centered</p>
</div>
</div>
</div>
一切正常。只是我想将div #add-article的内容置于div .main-content的中间，但不能正常工作。我已将CSS属性margin: 0 auto;应用于div .main-content和#add-article，但没有任何变化。
请帮我解决这个问题，谢谢。
答案 0 :(得分：1)
您可以设置以下css：
.main-content {
text-align: center;
}
// If you want the #add-article div to be size of content
#add-article {
display: inline-block;
}
答案 1 :(得分：1)
使用text-align: center;会使您的内容居中。
但是如果你想让你的容器居中而不是内容，你应该应用margin: 0 auto;解决方案，只为元素添加一些宽度。
请使用以下两种解决方案查看此jsfiddle：https://jsfiddle.net/mityaustinov/kz763h50/1/
答案 2 :(得分：0)
我所做的一切都是为了让“我想要集中” - 文字成为中心：
#add-article{
text-align: center;
}
我在你的CSS的最后一行写道。