HTML 导航栏下拉菜单在尝试使其粘滞时变得无响应

Question

我正在尝试将粘性导航栏添加到我正在创建的示例网页中。下面附上了代码的工作示例。但是，当我一直向下滚动时，我的导航栏下拉列表停止工作。再次向上滚动时它工作正常。我不确定这里出了什么问题。感谢您对这里出了什么问题的任何想法。

.header {
    padding: 10px;
    text-align: center;
    background: black;
    color: white;
}

.navbar {
    overflow: hidden;
    background-color: #47494f;
    z-index: 5;
}

.keepItTop {
    position: -webkit-sticky; /* Safari */
    position: sticky;
    top: 0;
}

/* Style the navigation bar links */
.navbar a {
    float: left;
    font-size: 16px;
    display: block;
    color: white;
    text-align: center;
    padding: 14px 20px;
    text-decoration: none;
}

/* Right-aligned link */
.navbar a.right {
    float: right;
}

/* Change color on hover */
.navbar a:hover, .dropdown:hover .dropbtn {
    background-color: #ddd;
    color: black;
}

/*Dropdown Menu*/
.dropdown {
  float: left;
  overflow: hidden;
}

.dropdown .dropbtn {
  font-size: 16px;
  border: none;
  outline: none;
  color: white;
  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: 6;
}

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

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

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

.homeVideo {
    width: 100%;
    height: auto;
}

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">

<div class="header">
    <h1>Sample WebPage</h1>
</div>

<div class="keepItTop">
    <div class="navbar">
        <a href="index.html">Home</a>
        <a href="about.html">About Me</a>
        <div class="dropdown">
            <button class="dropbtn">Games
                <i class="fa fa-caret-down"></i>
            </button>
            <div class="dropdown-content">
                <a href="swimming.html">Swimming</a>
                <a href="badminton.html">Badminton</a>
            </div>
        </div>
        <a href="contact.html">Contact Us</a>
    </div>
</div>

<div>
    <video class="homeVideo" autoplay muted loop>
        <source src="https://www.w3schools.com/html/mov_bbb.mp4" type="video/mp4">
    </video>
</div>

Answer 1

您的视频的 z 堆叠级别高于您的菜单。将菜单置于其上方。

.header {
    padding: 10px;
    text-align: center;
    background: black;
    color: white;
}

.navbar {
    overflow: hidden;
    background-color: #47494f;
    z-index: 5;
}

.keepItTop {
    position: -webkit-sticky; /* Safari */
    position: sticky;
    top: 0;
    z-index: 99; /* <----------------------- HERE */
}

/* Style the navigation bar links */
.navbar a {
    float: left;
    font-size: 16px;
    display: block;
    color: white;
    text-align: center;
    padding: 14px 20px;
    text-decoration: none;
}

/* Right-aligned link */
.navbar a.right {
    float: right;
}

/* Change color on hover */
.navbar a:hover, .dropdown:hover .dropbtn {
    background-color: #ddd;
    color: black;
}

/*Dropdown Menu*/
.dropdown {
  float: left;
  overflow: hidden;
}

.dropdown .dropbtn {
  font-size: 16px;
  border: none;
  outline: none;
  color: white;
  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: 6;
}

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

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

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

.homeVideo {
    width: 100%;
    height: auto;
}

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">

<div class="header">
    <h1>Sample WebPage</h1>
</div>

<div class="keepItTop">
    <div class="navbar">
        <a href="index.html">Home</a>
        <a href="about.html">About Me</a>
        <div class="dropdown">
            <button class="dropbtn">Games
                <i class="fa fa-caret-down"></i>
            </button>
            <div class="dropdown-content">
                <a href="swimming.html">Swimming</a>
                <a href="badminton.html">Badminton</a>
            </div>
        </div>
        <a href="contact.html">Contact Us</a>
    </div>
</div>

<div>
    <video class="homeVideo" autoplay muted loop>
        <source src="https://www.w3schools.com/html/mov_bbb.mp4" type="video/mp4">
    </video>
</div>

HTML 导航栏下拉菜单在尝试使其粘滞时变得无响应

HTML nav bar dropdown become unresponsive when trying to make it sticky

html

sticky

navbar

drop-down-menu