body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #202122;
}

header {
    background-color: #f8f9fa;
    border-bottom: 1px solid #a2a9b1;
    padding: 10px 15px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

header #p-logo a {
    display: block;
    width: 150px;
    height: 50px;
    background: url('https://upload.wikimedia.org/wikipedia/commons/b/b3/Wikipedia-logo-v2-en.png') no-repeat center;
    background-size: contain;
    text-indent: -9999px;
}

header #p-search {
    flex: 1;
    text-align: right;
}

header #p-search form {
    display: inline-block;
}

header #p-search input[type="search"] {
    padding: 5px;
    border: 1px solid #a2a9b1;
    border-radius: 5px;
}

header #p-search input[type="submit"] {
    background-color: #36c;
    color: #fff;
    border: none;
    padding: 5px 10px;
    margin-left: 5px;
    border-radius: 5px;
    cursor: pointer;
}

#container {
    display: flex;
    flex-wrap: nowrap;
    margin: 15px;
}

aside {
    width: 200px;
    background-color: #f8f9fa;
    border: 1px solid #a2a9b1;
    padding: 10px;
    margin-right: 15px;
    flex-shrink: 0;
}

aside ul {
    list-style: none;
    padding: 0;
}

aside ul li a {
    text-decoration: none;
    color: #36c;
}

main {
    flex-grow: 1;
    background-color: #fff;
    border: 1px solid #a2a9b1;
    padding: 15px;
}

.article-section {
    margin-bottom: 15px;
    padding: 10px;
    border: 1px solid #ccd;
    background-color: #f8f9fa;
}

.article-section h2 {
    margin-top: 0;
}

footer {
    background-color: #f8f9fa;
    border-top: 1px solid #a2a9b1;
    text-align: center;
    padding: 10px;
    margin-top: 15px;
}

@media (max-width: 768px) {
    #container {
        flex-wrap: wrap;
    }

    aside {
        width: 100%;
        margin-right: 0;
        margin-bottom: 15px;
    }
}