在响应式菜单中，它将两个链接放在同一行

Question

当我放置一个小屏幕时，菜单将 link“下拉菜单”和“关于”放在同一行。我想像其他人一样将“关于”放在下拉列表下方。只有当屏幕小的时候（当它是手机大小时phone），当屏幕大的时候效果很好，所以要检查它你应该缩小浏览器的大小screen.The问题是它将“下拉菜单”和“关于”放在同一行。

/* Toggle between adding and removing the "responsive" class to topnav when the user clicks on the icon */
function myFunction() {
  var x = document.getElementById("myTopnav");
  if (x.className === "topnav") {
    x.className += " responsive";
  } else {
    x.className = "topnav";
  }
}

 /* Add a black background color to the top navigation */
.topnav {
  background-color: white;
  overflow: hidden;
  text-align: center;
}

/* Style the links inside the navigation bar */
.topnav a {
  /*float: left;*/
  display: inline-flex;
  color: black;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

/* Add an active class to highlight the current page */
.active {
  background-color: #4CAF50;
  color: white;
}

/* Hide the link that should open and close the topnav on small screens */
.topnav .icon {
  display: none;
}

/* Dropdown container - needed to position the dropdown content */
.dropdown {
  /*float: left;*/
  overflow: hidden;
  display: inline-flex;
}

/* Style the dropdown button to fit inside the topnav */
.dropdown .dropbtn {
 
  font-size: 17px;
  border: none;
  outline: none;
  color: black;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
  
}

/* Style the dropdown content (hidden by default) */
.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

/* Style the links inside the dropdown */
.dropdown-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

/* Add a dark background on topnav links and the dropdown button on hover */
.topnav a:hover, .dropdown:hover .dropbtn {
  background-color: #555;
  color: white;
}

/* Add a grey background to dropdown links on hover */
.dropdown-content a:hover {
  background-color: #ddd;
  color: black;
}

/* Show the dropdown menu when the user moves the mouse over the dropdown button */
.dropdown:hover .dropdown-content {
  display: block;
}

/* When the screen is less than 600 pixels wide, hide all links, except for the first one ("Home"). Show the link that contains should open and close the topnav (.icon) */
@media screen and (max-width: 600px) {
  .topnav a:not(:first-child), .dropdown .dropbtn {
    display: none;
  }
  .topnav a.icon {
    float: right;
    display: block;
  }
}

/* The "responsive" class is added to the topnav with JavaScript when the user clicks on the icon. This class makes the topnav look good on small screens (display the links vertically instead of horizontally) */
@media screen and (max-width: 600px) {
  .topnav.responsive {position: relative;}
  .topnav.responsive a.icon {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
  .topnav.responsive .dropdown {float: left;}
  .topnav.responsive .dropdown-content {position: relative;}
  .topnav.responsive .dropdown .dropbtn {
    display: block;
    width: 100%;
    text-align: left;
  }
}

<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
        <LINK REL=StyleSheet HREF="estilosMenu.css?<?php echo date('l jS \of F Y h:i:s A'); ?>" TYPE="text/css">
        <script src="menu.js?<?php echo date('l jS \of F Y h:i:s A'); ?>"></script>
    </head>
    <body>
         <div class="topnav" id="myTopnav">
            <a href="#home" class="active">Home</a>
            <a href="#news">News</a>
            <a href="#contact">Contact</a>
            <div class="dropdown">
                <!--<a href="#news">Dropdown</a>-->
              <button class="dropbtn">Dropdown
                <i class="fa fa-caret-down"></i>
              </button>
              <div class="dropdown-content">
                <a href="#">Link 1</a>
                <a href="#">Link 2</a>
                <a href="#">Link 3</a>
              </div>
            </div>
            <a href="#about">About</a>
            <a href="javascript:void(0);" class="icon" onclick="myFunction()">&#9776;</a>
          </div> 
    </body>
</html>

Answer 1

这是由于手机屏幕显示的宽度问题。尝试将 width:100% 属性添加到下拉列表中。将宽度属性添加到以下 class:

.topnav.responsive .dropdown{
  float: left; 
  display:block;
  width:100%
 }

Answer 2

下拉菜单向左浮动，因此可以在其旁边放置以下项目。按照其他答案中的建议将下拉菜单的 width 设置为 100%，但它会留下不均匀的垂直间距并将下拉菜单的子项推到最右边。

要解决浮动下拉列表的根本问题，请将 clear: both 添加到 .topnav.responsive a 和 .topnav.responsive .dropdown（均在 @media screen 规则内）：

@media screen and (max-width: 600px) {
  ...
  .topnav.responsive a {
    ...
    clear: both;
  }
  .topnav.responsive .dropdown {
    ...
    clear: both;
  }
  ...
}

Answer 3

function myFunction() {
  var x = document.getElementById("myTopnav");
  if (x.className === "topnav") {
    x.className += " responsive";
  } else {
    x.className = "topnav";
  }
}

body {margin:0;font-family:Arial}
.topnav {
  overflow: hidden;
  background-color: #fff;
}

.topnav a {
  float: left;
  display: block;
  color: #111;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

.active {
  background-color: #4CAF50;
  color: white;
}

.topnav .icon {
  display: none;
}

.dropdown {
  float: left;
  overflow: hidden;
}

.dropdown .dropbtn {
  font-size: 17px;    
  border: none;
  outline: none;
  color: #111;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}

.dropdown-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}

.dropdown-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}

.topnav a:hover, .dropdown:hover .dropbtn {
  background-color: #555;
  color: white;
}

.dropdown-content a:hover {
  background-color: #ddd;
  color: black;
}

.dropdown:hover .dropdown-content {
  display: block;
}

@media screen and (max-width: 600px) {
  .topnav a:not(:first-child), .dropdown .dropbtn {
    display: none;
  }
  .topnav a.icon {
    float: right;
    display: block;
  }
}

@media screen and (max-width: 600px) {
  .topnav.responsive {position: relative;}
  .topnav.responsive .icon {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
  .topnav.responsive .dropdown {float: none;}
  .topnav.responsive .dropdown-content {position: relative;}
  .topnav.responsive .dropdown .dropbtn {
    display: block;
    width: 100%;
    text-align: left;
  }
}

<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
        <link REL=StyleSheet HREF="estilosMenu.css?<?php echo date('l jS \of F Y h:i:s A'); ?>" TYPE="text/css">
        <script src="menu.js?<?php echo date('l jS \of F Y h:i:s A'); ?>"></script>
        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
    </head>
    <body>
         <div class="topnav" id="myTopnav">
  <a href="#home" class="active">Home</a>
  <a href="#news">News</a>
  <a href="#contact">Contact</a>
  <div class="dropdown">
    <button class="dropbtn">Dropdown 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content">
      <a href="#">Link 1</a>
      <a href="#">Link 2</a>
      <a href="#">Link 3</a>
    </div>
  </div> 
  <a href="#about">About</a>
  <a href="javascript:void(0);" style="font-size:15px;padding: 11.5px 16px;" class="icon" onclick="myFunction()">&#9776;</a>
</div>
    </body>
</html>

这个怎么样？

在响应式菜单中，它将两个链接放在同一行

in responsive menu it puts two links on the same line

html

javascript

css

php

drop-down-menu