body {
    margin: 0;
    padding: 0;
    font-family: Arial, Verdana, sans-serif;
    background-color: #e0e0e0;
    color: #000000;
}

#container {
    display: table;
    width: 100%;
    height: 100vh;
}

#sidebar {
    display: table-cell;
    width: 180px;
    background-color: #6699cc;
    border-right: 3px solid #003366;
    vertical-align: top;
    padding: 20px 0;
}

#sidebar h2 {
    color: #ffffff;
    text-align: center;
    font-size: 18px;
    margin: 0 0 20px 0;
    text-shadow: 2px 2px #003366;
}

#sidebar a {
    display: block;
    padding: 10px 20px;
    color: #ffffff;
    text-decoration: none;
    border-top: 1px solid #3366aa;
    border-bottom: 1px solid #003366;
    background-color: #5588bb;
    margin: 2px 10px;
}

#sidebar a:hover {
    background-color: #3366aa;
}

#main {
    display: table-cell;
    vertical-align: top;
    padding: 30px;
}

.content {
    background-color: #ffffff;
    border: 2px solid #003366;
    padding: 30px;
    max-width: 800px;
}

h1 {
    color: #003366;
    border-bottom: 3px double #6699cc;
    padding-bottom: 10px;
}

h2 {
    color: #336699;
    margin-top: 20px;
}

hr {
    border: 0;
    height: 2px;
    background-color: #6699cc;
    margin: 20px 0;
}

.footer {
    margin-top: 30px;
    padding-top: 10px;
    border-top: 1px solid #cccccc;
    font-size: 12px;
    color: #666666;
    text-align: center;
}

ul {
    line-height: 1.8;
}

.update {
    background-color: #ffffcc;
    border: 1px solid #cccc99;
    padding: 10px;
    margin: 15px 0;
}

@media (max-width: 768px) {
    #container {
        display: block;
    }

    #sidebar {
        display: block;
        width: 100%;
        border-right: none;
        border-bottom: 3px solid #003366;
        padding: 10px 0;
    }

    #sidebar h2 {
        margin: 10px 0;
    }

    #sidebar a {
        display: inline-block;
        margin: 2px 5px;
        padding: 8px 15px;
        font-size: 14px;
    }

    #main {
        display: block;
        padding: 15px;
    }
}