body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 20px auto;
    padding: 0 20px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.menu-bar {
    margin-bottom: 30px;
}

.menu-items {
    display: flex;
    gap: 20px;
    padding: 10px 0;
    border-bottom: 1px solid #ddd;
}

.menu-items a {
    text-decoration: none;
    color: #333;
    padding: 5px 10px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.menu-items a:hover {
    background-color: #e0e0e0;
}

.menu-items a.active {
    background-color: #333;
    color: white;
}

.subtitle {
    font-size: 1.2em;
    color: #666;
    margin-bottom: 30px;
    font-weight: 300;
}

.content-wrapper {
    display: flex;
    flex: 1;
    gap: 20px;
}

.sidebar {
    width: 250px;
    background-color: white;
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    transition: width 0.3s;
}

.sidebar.collapsed {
    width: 50px;
    overflow: hidden;
}

.sidebar-content {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.sidebar.collapsed .sidebar-content {
    display: none;
}

.sidebar:not(.collapsed) .sidebar-content {
    display: flex;
}


.toggle-sidebar {
    background: none;
    border: none;
    font-size: 1.2em;
    cursor: pointer;
    margin-bottom: 10px;
    padding: 5px;
    width: 100%;
    text-align: left;
}

.sidebar.collapsed. toggle-sidebar {
    margin-bottom: 0;
    text-align: center;
}

#search {
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.category-item {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 8px;
}

.category-count {
    color: #666;
    font-size: 0.8em;
}

.main-content {
    flex: 1;
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.sort-options {
    margin-bottom: 20px;
}

#sort {
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.content-card {
    border: 1px dashed #ddd;
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 15px;
    cursor: pointer;
    transition: box-shadow 0.3s;
}

.content-card:hover {
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.content-title {
    font-weight: 600;
    margin-bottom: 5px;
}

.content-description {
    color: #666;
    margin-bottom: 10px;
    font-size: 0.9em;
}

.content-meta {
    display: flex;
    gap: 10px;
    font-size: 0.8em;
    color: #888;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.1);
    z-index: 1000;
}

.modal-content {
    position: relative;
    width: 90%;
    height: 90%;
    margin: 2% auto;
    background-color: white;
    padding: 20px;
    border-radius: 8px;
}

.close {
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    z-index: 1001;
}

#content-frame {
    width: 100%;
    height: 100%;
}

footer {
    margin-top: 40px;
    padding: 20px 0;
    text-align: center;
    color: #666;
    border-top: 1px solid #ddd;
}

.about-content {
    background-color: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    flex: 1;
}

.contact-info {
    margin-top: 30px;
}

.contact-info a {
    color: #333;
    text-decoration: none;
}

.contact-info a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .content-wrapper {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
    }
    
    .sidebar.collapsed {
        width: 100%;
        height: 50px;
    }
}