/* Global Reset */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
    line-height: 1.6;
    background-color: #f8f9fa; /* Light gray background */
    color: #212529; /* Dark text for readability */
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header Styling */
.viewer-header {
    background-color: #343a40; /* Dark header background */
    color: #ffffff; /* White text */
    padding: 1rem 1.5rem;
    text-align: center;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 3px solid #007bff; /* Accent color */
}

.viewer-header h1 {
    font-size: 1.8em;
    margin: 0;
}

.viewer-header .back-to-home {
    color: #ffffff;
    text-decoration: none;
    font-size: 0.9em;
    padding: 0.4rem 0.8rem;
    border: 1px solid #ffffff;
    border-radius: 5px;
    transition: background-color 0.2s, color 0.2s;
}

.viewer-header .back-to-home:hover {
    background-color: #ffffff;
    color: #343a40;
}

/* Main Container for Two-Pane Layout */
.viewer-container {
    display: flex;
    flex-grow: 1;
    width: 100%;
    max-width: 1400px; /* Max width for larger screens */
    margin: 15px auto; /* Centering and space from header */
    padding: 0 15px; /* Padding on the sides */
    gap: 20px; /* Space between nav and content panes */
}

/* Navigation Pane (Left) */
.viewer-nav {
    flex: 0 0 280px; /* Fixed width for nav, adjust as needed */
    background-color: #ffffff; /* White background for nav */
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    overflow-y: auto; /* Scroll if content exceeds height */
    max-height: calc(100vh - 120px); /* Adjust based on header/footer */
}

.viewer-nav h2 {
    font-size: 1.4em;
    color: #007bff; /* Accent color for heading */
    margin-top: 0;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid #dee2e6; /* Light border */
}

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

.viewer-nav ul li a {
    display: block;
    text-decoration: none;
    color: #343a40; /* Dark link color */
    padding: 0.6rem 0.8rem;
    margin-bottom: 0.3rem;
    border-radius: 5px;
    transition: background-color 0.2s, color 0.2s;
    font-size: 0.95em;
}

.viewer-nav ul li a:hover {
    background-color: #e9ecef; /* Light hover background */
    color: #0056b3; /* Darker blue on hover */
}

.viewer-nav ul li a.active {
    background-color: #007bff; /* Blue background for active link */
    color: #ffffff; /* White text for active link */
    font-weight: bold;
}

/* Content Pane (Right) */
.viewer-content {
    flex-grow: 1; /* Takes remaining space */
    background-color: #ffffff; /* White background for content */
    padding: 1.5rem 2rem; /* More padding for content */
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    overflow-y: auto; /* Scroll if content exceeds height */
    max-height: calc(100vh - 120px); /* Adjust based on header/footer */
}

/* Basic Styling for Rendered Markdown in .viewer-content */
.viewer-content h1, .viewer-content h2, .viewer-content h3, .viewer-content h4, .viewer-content h5, .viewer-content h6 {
    color: #2c3e50;
    margin-top: 2rem;
    margin-bottom: 1.2rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid #eaecef;
}
.viewer-content h1:first-child, .viewer-content h2:first-child, .viewer-content h3:first-child {
    margin-top: 0.2rem;
}
.viewer-content h1 { font-size: 2em; }
.viewer-content h2 { font-size: 1.7em; }
.viewer-content h3 { font-size: 1.4em; }
.viewer-content h4 { font-size: 1.2em; border-bottom: none; }
.viewer-content h5 { font-size: 1.1em; border-bottom: none; }
.viewer-content h6 { font-size: 1em; border-bottom: none; color: #6c757d; }

.viewer-content p {
    margin-bottom: 1.5rem;
    line-height: 1.8;
    color: #34495e;
}

.viewer-content a {
    color: #3498db;
    text-decoration: none;
    transition: color 0.2s ease-in-out;
}

.viewer-content a:hover {
    color: #2980b9;
    text-decoration: underline;
}

.viewer-content code {
    background-color: #f3f4f6;
    color: #e74c3c;
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
}

.viewer-content pre {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 1.2em;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 1.5rem;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
    line-height: 1.6;
}

.viewer-content ul, .viewer-content ol {
    margin-left: 25px;
    margin-bottom: 1.2rem;
    padding-left: 10px;
}

.viewer-content li {
    margin-bottom: 0.6rem;
}

.viewer-content code {
    background-color: #e9ecef; /* Light background for inline code */
    color: #c7254e; /* Bootstrap-like color for code */
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
}

.viewer-content pre {
    background-color: #282c34; /* Dark background for code blocks */
    color: #abb2bf; /* Light text for dark background */
    padding: 1em;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 1.2rem;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
    line-height: 1.5;
}

.viewer-content pre code {
    background-color: transparent; /* Reset for code inside pre */
    color: inherit;
    padding: 0;
    font-size: inherit;
}

.viewer-content table {
    width: auto; /* Let table size itself, or 100% if preferred */
    max-width: 100%;
    border-collapse: collapse;
    margin-bottom: 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    font-size: 0.9em;
}

.viewer-content th, .viewer-content td {
    border: 1px solid #dee2e6; /* Lighter border for tables */
    padding: 0.8rem 1rem;
    text-align: left;
}

.viewer-content th {
    background-color: #f8f9fa; /* Very light gray for table headers */
    font-weight: 600;
}

.viewer-content blockquote {
    border-left: 5px solid #007bff; /* Blue accent for blockquotes */
    padding: 0.8rem 1.2rem;
    margin-left: 0;
    margin-right: 0;
    margin-bottom: 1.2rem;
    background-color: #f0f8ff; /* Light blue background */
    color: #334155;
    font-style: italic;
}
.viewer-content blockquote p:last-child {
    margin-bottom: 0;
}

.viewer-content a {
    color: #007bff;
    text-decoration: none;
}

.viewer-content a:hover {
    text-decoration: underline;
    color: #0056b3;
}

.viewer-content img {
    max-width: 100%;
    height: auto;
    border-radius: 5px;
    margin: 0.5em 0 1em 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

/* Responsive Adjustments */
@media (max-width: 768px) {
    .viewer-container {
        flex-direction: column;
        margin-top: 10px;
        padding: 0 10px;
    }
    .viewer-nav, .viewer-content {
        flex: 1 1 auto; /* Allow them to grow and shrink */
        max-height: none; /* Remove fixed height for stacked layout */
        width: 100%;
    }
    .viewer-nav {
        margin-bottom: 15px; /* Space between nav and content when stacked */
        max-height: 40vh; /* Limit height when stacked */
    }
    .viewer-header {
        padding: 0.8rem 1rem;
        flex-direction: column;
        gap: 0.5rem;
    }
    .viewer-header h1 {
        font-size: 1.5em;
    }
}

/* Print styles */
@media print {
    body {
        background-color: #fff;
        padding: 0;
        margin: 0.5in;
        font-size: 10pt;
    }
    .viewer-header, .viewer-nav {
        display: none !important;
    }
    .viewer-container {
        flex-direction: column !important;
        margin: 0 !important;
        padding: 0 !important;
        gap: 0 !important;
    }
    .viewer-content {
        flex: 1 !important;
        box-shadow: none !important;
        border: none !important;
        padding: 0 !important;
        max-height: none !important;
        overflow: visible !important;
    }
    .viewer-content h1, .viewer-content h2, .viewer-content h3, .viewer-content h4, .viewer-content h5, .viewer-content h6 {
        page-break-after: avoid;
    }
    .viewer-content table, .viewer-content blockquote, .viewer-content pre {
        page-break-inside: avoid;
    }
    .viewer-content a {
        color: #000 !important; /* Black links for print */
        text-decoration: underline !important;
    }
    .viewer-content a[href^="http"]:after, .viewer-content a[href^="//"]:after {
        content: " (" attr(href) ")"; /* Show full URLs for external links */
        font-size: 0.9em;
    }
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol"; /* Modern system font stack */
    line-height: 1.6;
    color: #212529; /* Darker text for better readability */
    background-color: #f8f9fa; /* Lighter gray background */
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header {
    background: #343a40; /* Consistent dark header */
    color: #ffffff;
    padding: 1rem 1.5rem; /* Adjusted padding */
    text-align: center;
    border-bottom: 3px solid #007bff; /* Accent color */
}

header h1 {
    margin: 0;
    font-size: 1.8rem; /* Kept original size, can be adjusted */
}

.container { /* This class might be used by older hub pages */
    display: flex;
    flex: 1;
    width: 90%;
    max-width: 1400px;
    margin: 20px auto;
    overflow: hidden;
    gap: 20px; /* Added gap for consistency with shared-readme-styles */
}

#sidebar {
    width: 250px;
    background-color: #333;
    color: white;
    padding: 15px;
    overflow-y: auto;
    height: 100%;
    box-sizing: border-box;
}

#sidebar h3 {
    margin-top: 0;
    color: #fff;
    border-bottom: 1px solid #555;
    padding-bottom: 10px;
}

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

#sidebar li a {
    color: #ddd;
    text-decoration: none;
    display: block;
    padding: 8px 0;
    transition: background-color 0.2s;
}

#sidebar li a:hover, #sidebar li a.active {
    color: #fff;
    background-color: #555;
}

#sidebar .subdirectory-group {
    margin-top: 10px;
    padding-top: 5px;
    border-top: 1px dashed #555;
}

#sidebar .subdirectory-group h4 {
    color: #bbb;
    font-size: 0.9em;
    margin-bottom: 5px;
}

#sidebar h2 {
    margin-top: 0;
    font-size: 1.4em; /* Consistent with .viewer-nav h2 */
    color: #007bff; /* Accent color */
    border-bottom: 1px solid #dee2e6;
    padding-bottom: 0.5rem;
    margin-bottom: 1rem;
}

#sidebar ul {
    list-style: none;
}

#sidebar ul li {
    margin-bottom: 0.3rem; /* Consistent with .viewer-nav */
}

#sidebar ul li a {
    text-decoration: none;
    color: #343a40; /* Dark link color */
    display: block;
    padding: 0.6rem 0.8rem; /* Consistent padding */
    border-radius: 5px;
    transition: background-color 0.2s, color 0.2s;
    font-size: 0.95em;
}

#sidebar ul li a:hover,
#sidebar ul li a.active {
    background-color: #e9ecef; /* Light hover background */
    color: #0056b3; /* Darker blue on hover */
}
#sidebar ul li a.active {
    background-color: #007bff;
    color: #ffffff;
    font-weight: bold;
}


/* Sub-navigation for module parts */
#sidebar ul ul {
    margin-left: 15px; /* Keep indentation */
    margin-top: 5px;
    font-size: 0.9em; /* Relative to parent */
}

#sidebar ul ul li a {
    padding: 0.4rem 0.6rem; /* Slightly smaller padding for sub-items */
    color: #495057; /* Slightly lighter than main links */
}

#sidebar ul ul li a:hover,
#sidebar ul ul li a.active {
    background-color: #dee2e6; /* Slightly darker hover for sub-items */
}
#sidebar ul ul li a.active {
    background-color: #007bff; /* Keep active consistent */
    color: #ffffff;
}


#content-area { /* Styles for a potential older content area */
    background: #ffffff; /* Cleaner white background */
    width: 75%;
    padding: 1.5rem 2rem; /* Consistent padding */
    overflow-y: auto;
    border-radius: 8px; /* Added for consistency */
    box-shadow: 0 2px 5px rgba(0,0,0,0.05); /* Subtle shadow */
    /* max-height: calc(100vh - 120px); */
}

/* Styles for rendered Markdown content in #content-area, aligned with shared-readme-styles.css */
#content-area h1, #content-area h2, #content-area h3, #content-area h4, #content-area h5, #content-area h6 {
    color: #343a40;
    margin-top: 1.8rem;
    margin-bottom: 1rem;
    padding-bottom: 0.4rem;
    border-bottom: 1px solid #e0e0e0;
}
#content-area h1:first-child, #content-area h2:first-child, #content-area h3:first-child {
    margin-top: 0.2rem;
}
#content-area h1 { font-size: 2em; }
#content-area h2 { font-size: 1.7em; }
#content-area h3 { font-size: 1.4em; }
#content-area h4 { font-size: 1.2em; border-bottom: none; }
#content-area h5 { font-size: 1.1em; border-bottom: none; }
#content-area h6 { font-size: 1em; border-bottom: none; color: #6c757d; }

#content-area p {
    margin-bottom: 1.2rem;
    line-height: 1.7;
}

#content-area ul, #content-area ol {
    margin-left: 25px;
    margin-bottom: 1.2rem;
    padding-left: 10px;
}

#content-area li {
    margin-bottom: 0.6rem;
}

#content-area code { /* Inline code */
    background-color: #e9ecef;
    color: #c7254e;
    padding: 0.2em 0.4em;
    border-radius: 3px;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
}

#content-area pre { /* Code blocks */
    background-color: #282c34;
    color: #abb2bf;
    padding: 1em;
    border-radius: 5px;
    overflow-x: auto;
    margin-bottom: 1.2rem;
    font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
    font-size: 0.9em;
    line-height: 1.5;
}

#content-area pre code {
    background-color: transparent;
    color: inherit;
    padding: 0;
    font-size: inherit;
}

#content-area table {
    width: auto;
    max-width: 100%;
    border-collapse: collapse;
    margin-bottom: 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.08);
    font-size: 0.9em;
}

#content-area th, #content-area td {
    border: 1px solid #dee2e6;
    padding: 0.8rem 1rem;
    text-align: left;
}

#content-area th {
    background-color: #f8f9fa;
    font-weight: 600;
}

#content-area blockquote {
    border-left: 5px solid #007bff;
    padding: 0.8rem 1.2rem;
    margin-left: 0;
    margin-right: 0;
    margin-bottom: 1.2rem;
    background-color: #f0f8ff;
    color: #334155;
    font-style: italic;
}
#content-area blockquote p:last-child {
    margin-bottom: 0;
}

#content-area a {
    color: #007bff;
    text-decoration: none;
}

#content-area a:hover {
    text-decoration: underline;
    color: #0056b3;
}

footer {
    text-align: center;
    padding: 1rem 1.5rem; /* Consistent padding */
    background: #343a40; /* Consistent dark footer */
    color: #ffffff;
    margin-top: auto;
}

/* Basic responsiveness */
.hub-card {
    background-color: #ffffff;
    border: 1px solid #dee2e6;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.hub-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.hub-card h2 {
    color: #007bff;
    margin-top: 0;
    margin-bottom: 0.5rem;
}

.hub-card p {
    color: #495057;
    margin-bottom: 1rem;
}

.hub-card a {
    color: #007bff;
    text-decoration: none;
    font-weight: bold;
}

.hub-card a:hover {
    text-decoration: underline;
}

#scroll-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background-color: #3498db;
    color: white;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s, background-color 0.3s;
    cursor: pointer;
    border: none;
    z-index: 1000;
}

#scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
}

#scroll-to-top:hover {
    background-color: #2980b9;
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
        width: 95%;
    }

    #sidebar, #content-area {
        width: 100%;
        height: auto; /* Adjust height for stacked layout */
        max-height: 50vh; /* Example, can be adjusted */
    }

    #sidebar {
        border-right: none;
        border-bottom: 1px solid #ddd;
        margin-bottom: 10px;
    }
}