html how to ensure that the header always on top
/* The navigation bar */
.navbar {
overflow: hidden;
background-color: #333;
position: fixed; /* Set
the navbar to fixed position */
top: 0;
/* Position the navbar at the top of the page */
width:
100%; /* Full width */
}
/* Links inside the navbar */
.navbar a {
float: left;
display:
block;
color: #f2f2f2;
text-align:
center;
padding: 14px 16px;
text-decoration: none;
}
/* Change background on mouse-over */
.navbar
a:hover {
background: #ddd;
color:
black;
}
/* Main
content */
.main {
margin-top: 30px; /* Add a top
margin to avoid content overlay */
}