My website has a header and it takes 20% of screen. I want an image (which is 90% of header height) right in the center of the header. I had no problems to center the image horizontally, but I can't center it vertically. Here's the code:
<!doctype html>
<html lang="en">
<head>
    <meta charset="utf-8" />
    <title>Website</title>
    <link rel="stylesheet" href="stylingpercent.css" />
</head>
<body>
    <header>
        <div class="logoheader" >
            <img class="mainlogo" src="logo.png" alt="logo">
        </div>
    </header>
</body>
</html>
body {
    margin:0px;
}
.logoheader{
    height: 20vh;
    background:rgb(1,1,1);
    margin:0px;
    text-align: center;
}
.mainlogo { 
    max-height:90%;
}
 
    