Metti semplicemente il CSS nello style all'interno del codice
codice:
<html>
<head>
<title>WiFi</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=yes">
<style>
body{
margin: 0;
padding: 0;
background: url(https://www.hotelexcelsiorbay.com/hotspot/sfondo.jpg);
background-size: cover;
background-position: center;
font-family: sans-serif;
}
.loginbox{
width: 300px;
height: 380px;
background: #fff;
color: #000;
top: 50%;
left: 50%;
position: absolute;
transform: translate(-50%,-50%);
border-radius: 15px;
box-sizing: border-box;
padding: 70px 30px;
}
.avatar{
width: 100px;
height: 100px;
border-radius: 50%;
position: absolute;
top: -50px;
left: calc(50% - 50px);
}
h1{
margin: 0;
padding: 0 0 20px;
text-align: center;
font-size: 22px;
color: #00297a;
}
h2{
margin: 0;
text-align: center;
font-size: 10px;
}
.loginbox input{
width: 100%;
margin-bottom: 0px;
}
.loginbox input[type="submit"]
{
border: none;
outline: none;
height: 40px;
background: #00297a ;
color: #fff;
font-size: 18px;
border-radius: 10px;
}
</style>
</head>
<body>
<div class="loginbox">
<img src="https://www.hotelexcelsiorbay.com/hotspot/avatar.png" class="avatar">
<h1>Hotel Excelsior Bay<br>Free WiFi<br><br><br><br><br><br><br></h1>
<form>
<input type="submit" name="" value="Connect">
</form>
<h2><a href="https://www.hotelexcelsiorbay.com/privacy-policy/" target="_blank" >Privacy Policy</a></h2>
</div>
</body>
</html>