body {
    font-family: 'Roboto', sans-serif;
    margin: 0;
    background-color: #ffffff;
    color: #000000;
}

.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 220px;
    height: 100%;
    background-color: #f7f7f7;
    border-right: 1px solid #cccccc;
    padding: 20px;
    box-sizing: border-box;
}

.sidebar h2 {
    margin-top: 0;
    font-size: 1.4rem;
    font-weight: 700;
}

.sidebar .subtitle {
    font-size: 0.85rem;
    color: #666666;
    margin-bottom: 20px;
}

.sidebar ul {
    list-style: none;
    padding: 0;
}

.sidebar ul li {
    margin: 12px 0;
}

.sidebar ul li a {
    color: #000000;
    text-decoration: none;
    font-weight: 500;
}

.sidebar ul li a:hover {
    text-decoration: underline;
}

.content {
    margin-left: 240px;
    padding: 40px;
    max-width: 900px;
}

header {
    text-align: left;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.2rem;
    margin-bottom: 5px;
}

header .subtitle {
    font-size: 1rem;
    color: #555555;
}

.section {
    margin-bottom: 40px;
    padding: 20px;
    background-color: #fefefe;
    border: 1px solid #dddddd;
    border-radius: 4px;
}

.section h2 {
    margin-top: 0;
    font-size: 1.5rem;
    border-bottom: 1px solid #cccccc;
    padding-bottom: 5px;
    margin-bottom: 15px;
}

.section pre {
    background-color: #f5f5f5;
    padding: 10px;
    border-radius: 3px;
    overflow-x: auto;
    border: 1px solid #e0e0e0;
}

.section code {
    background-color: #f0f0f0;
    padding: 2px 4px;
    border-radius: 2px;
}

a {
    color: #0000ee;
}

a:hover {
    text-decoration: underline;
}

footer {
    margin-top: 50px;
    padding: 20px 0;
    border-top: 1px solid #cccccc;
    font-size: 0.85rem;
    color: #555555;
}

@media (max-width: 768px) {
    .sidebar {
        position: relative;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 1px solid #cccccc;
    }
    .sidebar ul {
        display: flex;
        flex-wrap: wrap;
    }
    .sidebar ul li {
        margin: 5px 15px;
    }
    .content {
        margin-left: 0;
        padding: 20px;
    }
}