body {
    margin: 0;
    padding: 0;
    background: #003366;
    font-family: Verdana, Arial, sans-serif;
    font-size: 14px;
}
#topnav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: #222;
    padding: 6px;
    text-align: center;
    border-bottom: 2px solid #000;
    z-index: 999;
}
#topnav a {
    color: #00ffcc;
    margin: 0 10px;
    text-decoration: none;
    font-weight: bold;
}
#topnav a:hover {
    text-decoration: underline;
}
#container {
    width: 780px;
    margin: 60px auto 20px auto; /* space for fixed nav */
    background: #ffffff;
    border: 1px solid #000;
}
#header {
    background: #336699;
    color: white;
    text-align: center;
    padding: 10px;
    border-bottom: 1px solid #000;
}
#header h1 {
    margin: 0;
    font-size: 20px;
}
#main {
    display: flex;
}
#sidebar {
    width: 180px;
    background: #eeeeee;
    padding: 10px;
    border-right: 1px solid #000;
}
#sidebar h3 {
    font-size: 13px;
    border-bottom: 1px solid #999;
}
#sidebar ul {
    padding-left: 15px;
}
#content {
    flex: 1;
    padding: 12px;
}
.float-box {
    float: left;
    margin: 0 10px 10px 0;
    border: 1px solid #000;
    background: #ffffff;
    padding: 4px;
}
.float-box img {
    display: block;
    width: 140px;
    height: 100px;
}
.box {
    margin-top: 10px;
    padding: 8px;
    border: 2px dashed #333;
    background: #ffffcc;
}
#footer {
    background: #222;
    color: white;
    text-align: center;
    font-size: 11px;
    padding: 6px;
    border-top: 1px solid #000;
}