目標:
覆蓋內容應位於頁面中間。在中間設置覆蓋內容
問題:
我無法使覆蓋內容(白色框)位於中間。我缺少什麼語法?
謝謝!
function openNav() {
document.getElementById("myNav").style.height = "100%";
}
function closeNav() {
document.getElementById("myNav").style.height = "0%";
}
body {
margin: 0;
font-family: 'Lato', sans-serif;
}
.overlay {
height: 0%;
width: 100%;
position: fixed;
z-index: 1;
top: 0;
left: 0;
background-color: rgb(0,0,0);
background-color: rgba(0,0,0, 0.8);
overflow-y: hidden;
transition: 0.5s;
}
.overlay-content {
position: relative;
top: 10%;
width: 70%;
text-align: left;
margin-top: 30px;
background: white
}
.overlay a {
padding: 8px;
text-decoration: none;
font-size: 36px;
color: #818181;
display: block;
transition: 0.3s;
}
.overlay a:hover, .overlay a:focus {
color: #f1f1f1;
}
.overlay .closebtn {
position: absolute;
top: 20px;
right: 45px;
font-size: 60px;
}
@media screen and (max-height: 450px) {
.overlay {overflow-y: auto;}
.overlay a {font-size: 20px}
.overlay .closebtn {
font-size: 40px;
top: 15px;
right: 35px;
}
}
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<title>JS Bin</title>
</head>
<body>
<div id="myNav" class="overlay">
<a href="javascript:void(0)" class="closebtn" onclick="closeNav()">×</a>
<div class="overlay-content">
<a href="#">About</a>
<a href="#">Services</a>
<a href="#">Clients</a>
<a href="#">Contact</a>
</div>
</div>
<h2>Fullscreen Overlay Nav Example</h2>
<p>Click on the element below to open the fullscreen overlay navigation menu.</p>
<p>In this example, the navigation menu will slide downwards from the top:</p>
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<span style="font-size:30px;cursor:pointer" onclick="openNav()">☰ open</span>
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</body>
</html>
你想居中垂直,水平還是兩者? [SO Docu:Centering - CSS](https://stackoverflow.com/documentation/css/299/centering#t=201704040840007262339) –