HTML / CSS：如何将导航栏移到中间？

Question

我刚接触CSS，正在制作一个导航栏。 目前，我的导航栏位于左侧，我想将整个导航栏移到中间。 我怎样才能做到这一点？

以下是代码。 提前致谢！

 /* Navigation bar */ #navigation_bar { list-style-type: none; margin: 0; position: fixed; background-color: #333; top: 0; Left: 0; width: 100%; } li { float: left; } li a, .dropbtn { display: inline-block; color: white; text-align: center; padding: 14px 16px; text-decoration: none; } li a:hover:not(.active), .dropdown:hover .dropbtn { background-color: #111; } li.dropdown { display: inline-block; } .dropdown-content { display: none; position: absolute; background-color: #f1f1f1; min-width: 160px; box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2); } .dropdown-content a { color: black; padding: 12px 16px; text-decoration: none; display: block; text-align: left; } .dropdown-content a:hover { background-color: #f1f1f1 } .dropdown:hover .dropdown-content { display: block; } .active { background-color: #4CAF50; } 

 <!--Navigation bar--> <ul id="navigation_bar"> <li><a class="active" href="navigation_bar/home.html">Home.</a></li> <li><a href="navigation_bar/promotion.html">Promotion.</a></li> <!--drop down menu--> <li class="dropdown"><a href="navigation_bar/hot_products.html" class="dropbtn">Hot Products.</a> <div class="dropdown-content"> <a herf="navigation_bar/sub_menu/sandwiches.html">Sandwiches</a> <a herf="navigation_bar/sub_menu/burger.html">Burger</a> <a herf="navigation_bar/sub_menu/rice.html">Rice</a> <a herf="navigation_bar/sub_menu/noodles.html">Noddles</a> </div> </li> <!--Back to normal--> <li><a href="navigation_bar/cold_products.html">Cold Products.</a></li> <li><a href="navigation_bar/snacks.html">Snacks.</a></li> <li><a href="navigation_bar/about_us.html">About Us.</a></li> <li><a href="navigation_bar/contact_us.html">Contact Us.</a></li> </ul> 

Answer 1

使用更新您的#navigation_bar

#navigation_bar {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
}

这是工作中的演示

 #navigation_bar { list-style-type: none; margin: 0; position: fixed; background-color: #333; top: 0; Left: 0; width: 100%; display: flex; align-items: center; justify-content: center; padding: 0; } li { float: left; } li a, .dropbtn { display: inline-block; color: white; text-align: center; padding: 14px 16px; text-decoration: none; } li a:hover:not(.active), .dropdown:hover .dropbtn { background-color: #111; } li.dropdown { display: inline-block; } .dropdown-content { display: none; position: absolute; background-color: #f1f1f1; min-width: 160px; box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2); } .dropdown-content a { color: black; padding: 12px 16px; text-decoration: none; display: block; text-align: left; } .dropdown-content a:hover { background-color: #f1f1f1 } .dropdown:hover .dropdown-content { display: block; } .active { background-color: #4CAF50; } 

  <ul id="navigation_bar"> <li><a class="active" href="navigation_bar/home.html">Home.</a></li> <li><a href="navigation_bar/promotion.html">Promotion.</a></li> <!--drop down menu--> <li class="dropdown"><a href="navigation_bar/hot_products.html" class="dropbtn">Hot Products.</a> <div class="dropdown-content"> <a herf="navigation_bar/sub_menu/sandwiches.html">Sandwiches</a> <a herf="navigation_bar/sub_menu/burger.html">Burger</a> <a herf="navigation_bar/sub_menu/rice.html">Rice</a> <a herf="navigation_bar/sub_menu/noodles.html">Noddles</a> </div> </li> <!--Back to normal--> <li><a href="navigation_bar/cold_products.html">Cold Products.</a></li> <li><a href="navigation_bar/snacks.html">Snacks.</a></li> <li><a href="navigation_bar/about_us.html">About Us.</a></li> <li><a href="navigation_bar/contact_us.html">Contact Us.</a></li> </ul> 

Answer 2

通过更改一些CSS代码，您可以轻松地做到这一点：

#navigation_bar {
   text-align: center;
}

#navigation_bar li {
    float: none;
    display: inline-block;
    vertical-align: top;
}
li .dropdown-content a:hover:not(.active) {
    background: #d0d0d0; /* for altering the hover effect on submenus */
}

我还创建了一个JSFiddle 。

Answer 3

将navigation_bar CSS更改为：

#navigation_bar { 
list-style-type: none;
margin: 0 auto;
position: fixed;
background-color: #333;
top: 0;   
width: auto;    
display: block;
float: left;
}

Answer 4

尝试这个

#navigation_bar{ text-align: center;}   /*add align center  */
li {display: inline; /* float:left; */} /* remove float left here and add display inline */