@import "https://fonts.googleapis.com/css2?family=Montserrat:wght@200;300;400;500;600;700&display=swap";

:root {
            /* Requested Colors */
            --primary-blue: hsl(218, 100%, 40%); /* The specific requested blue */
            --bg-grey: #f4f5f6;
            
            /* UI Colors */
            --text-main: #242424;
            --text-light: #64748b;
            --white: #ffffff;
            --border: #e2e8f0;
            --code-bg: #f1f5f9;
            --bg-secondary: #f8fafc; /* Added for dropdown hover */
        }

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

        /* Use smooth scroll for anchor links */
        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Inter', sans-serif;
            background-color: var(--bg-grey);
            color: var(--text-main);
            line-height: 1.6;
            font-size: 16px;
        }

        /* Layout Structure */
        .app-container {
            display: grid;
            grid-template-columns: 1fr;
            gap: 2rem;
            max-width: 1400px; /* Wider container for side-by-side */
            margin: 0 auto;
            padding: 2rem;
            padding-top: 0; /* Adjust padding since header is now outside */
        }

        @media (min-width: 1024px) {
            .app-container {
                /* NEW GRID: Sidebar (TOC) on the left, Content on the right */
                grid-template-columns: 300px minmax(0, 3fr); /* TOC fixed 300px, Content takes space */
            }
        }

        /* Header (New Top Menu/Navbar) - Full width, not part of grid */
        header {
            background: var(--white);
            padding: 1rem 2rem;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
            display: flex;
            justify-content: flex-start; 
            align-items: center;
            border-bottom: 1px solid var(--border);
            gap: 4rem; 
        }

        .brand img {
            height: 60px; 
            width: auto;
            display: block;
            border-radius: 0; 
            box-shadow: none; 
            margin: 0; 
        }
        
        /* Main Navigation Links */
        .main-nav ul {
            list-style: none;
            display: flex;
            gap: 2rem;
            padding: 0;
            margin: 0;
        }

        .main-nav a {
            color: var(--text-main);
            font-weight: 600;
            padding: 0.5rem 0;
            border-bottom: 2px solid transparent;
            transition: color 0.2s, border-bottom-color 0.2s;
        }
        
        .main-nav a:hover {
            color: var(--primary-blue);
            border-bottom-color: var(--primary-blue);
            text-decoration: none;
        }
        
        /* --- Dropdown Styles --- */
        .dropdown {
            position: relative;
            display: inline-block;
        }

        .dropdown .dropbtn {
            /* Add space for the arrow icon */
            padding-right: 1.5rem;
            cursor: pointer;
        }
        
        .dropdown .dropbtn::after {
            content: '▼';
            font-size: 0.6rem;
            margin-left: 0.4rem;
            position: absolute;
            top: 50%;
            /* Adjust positioning relative to the parent li */
            right: 0.2rem; 
            transform: translateY(-50%);
            transition: transform 0.2s;
        }

        .dropdown:hover .dropbtn::after {
            transform: translateY(-50%) rotate(180deg);
        }

        .dropdown-content {
            display: none;
            position: absolute;
            background-color: var(--white);
            min-width: 200px;
            box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
            z-index: 100;
            top: 100%; 
            left: 0;
            border-radius: 8px;
            overflow: hidden;
            border: 1px solid var(--border);
            /* Give it some top margin to clear the parent link's bottom border */
            margin-top: 5px; 
        }

        .dropdown-content a {
            color: var(--text-main);
            padding: 10px 16px;
            text-decoration: none;
            display: block;
            border-bottom: none; /* Override main-nav border */
            font-weight: 400;
            white-space: nowrap; /* Prevent wrapping in dropdown */
        }
        
        .dropdown-content a:hover {
            background-color: var(--bg-secondary);
            color: var(--primary-blue);
            text-decoration: none;
        }

        .dropdown:hover .dropdown-content {
            display: block;
        }
        /* --- End Dropdown Styles --- */
        
        /* Mobile navigation adjustments */
        @media (max-width: 768px) {
            header {
                flex-direction: column;
                gap: 1rem;
                padding: 1rem;
            }
            .main-nav ul {
                gap: 0.8rem;
                flex-wrap: wrap;
                justify-content: center;
            }
            .search-wrapper {
                margin: 0 1rem;
            }
            /* Adjust dropdown for mobile view if needed (hiding for simplicity here) */
            .dropdown-content {
                position: static;
                box-shadow: none;
                border: none;
                margin-top: 0;
            }
        }


        /* Main Content Area */
        main {
            background: var(--white);
            padding: 3rem;
            border-radius: 12px;
            box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
            min-width: 0; 
            /* On desktop (1024px+), main content is in the second column */
            grid-column: 1 / 2; 
        }
        
        @media (min-width: 1024px) {
            main {
                grid-column: 2 / 3;
            }
        }

        /* --- Breadcrumb Styling --- */
        #breadcrumb-container {
            margin-top: -1rem; /* Pull up closer to the title */
            margin-bottom: 2rem;
            font-size: 0.85rem;
            color: var(--text-light);
        }

        .breadcrumb-item {
            display: inline-block;
        }

        /* Make all links in the breadcrumb inherit the primary blue color */
        .breadcrumb-item a {
            color: var(--primary-blue); /* Updated to primary blue */
            text-decoration: none;
            font-weight: 500; /* Slightly bolder for visibility */
        }

        .breadcrumb-item a:hover {
            color: var(--primary-blue);
            text-decoration: underline;
        }

        .breadcrumb-separator {
            margin: 0 0.5rem;
            color: #ccc;
        }

        .breadcrumb-item.active-item {
            color: var(--text-main);
            font-weight: 500;
        }
        /* --- End Breadcrumb Styling --- */


        /* Typography */
        h1, h2, h3, h4, h5, h6 {
            color: var(--text-main);
            font-weight: 700;
            line-height: 1.3;
            margin-top: 2.5rem;
            margin-bottom: 1rem;
            /* CRITICAL FIX: Ensures the target heading lands 120px below the top edge of the viewport, clear of the fixed headers. */
            scroll-margin-top: 120px; 
        }

        h1 {
            color: var(--text-main);
            font-size: 2.25rem;
            padding-bottom: 1rem;
            border-bottom: 2px solid var(--border);
            margin-top: 0;
        }

        h2 {
            font-size: 1.75rem;
            color: var(--text-main);
            border-left: 4px solid var(--primary-blue);
            padding-left: 1rem;
        }

        h3 {
            font-size: 1.35rem;
            color: var(--text-main);
        }

        p {
            margin-bottom: 1.25rem;
            color: var(--text-main);
        }

        a {
            color: var(--primary-blue);
            text-decoration: none;
            font-weight: 500;
            transition: all 0.2s;
        }

        a:hover {
            text-decoration: underline;
        }

        /* Blockquotes */
        blockquote {
            background: #eff6ff; /* Light blue tint */
            border-left: 4px solid var(--primary-blue);
            margin: 1.5rem 0;
            padding: 1rem 1.5rem;
            border-radius: 0 8px 8px 0;
            font-style: italic;
            color: var(--text-main);
        }

        /* Lists */
        ul, ol {
            padding-left: 1.5rem;
            margin-bottom: 1.5rem;
        }
        
        li {
            margin-bottom: 0.5rem;
        }

        li::marker {
            color: var(--primary-blue);
        }

        /* Tables */
        .table-wrapper {
            overflow-x: auto;
            margin: 2rem 0;
            border-radius: 8px;
            border: 1px solid var(--border);
        }

        table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.95rem;
        }

        th {
            background: var(--primary-blue);
            color: var(--white);
            padding: 1rem;
            text-align: left;
            font-weight: 600;
        }

        td {
            padding: 1rem;
            border-bottom: 1px solid var(--border);
        }

        tr:last-child td {
            border-bottom: none;
        }

        tr:nth-child(even) {
            background-color: #f8fafc;
        }

        /* Images */
        img {
            max-width: 100%;
            height: auto;
            border-radius: 8px; 
            margin: 1.5rem 0; 
            box-shadow: 0 4px 6px -1px rgba(0,0,0,0.1); 
            display: block; 
        }
        
        /* Placeholder for missing images */
        img[src="https://placehold.co/600x400/e2e8f0/64748b?text=Diagram+Placeholder"] {
            /* We can't display local images, so we style them or hide them slightly */
            background-color: #e2e8f0;
            border: 1px dashed var(--text-light);
            padding: 20px;
            font-style: italic;
            position: relative;
        }
        
        img[alt]::after {
             content: " (Image: " attr(alt) ")";
             display: block;
             font-size: 0.8rem;
             color: #666;
        }

        /* Left Sidebar Navigation (TOC) */
        aside {
            display: none;
        }

        @media (min-width: 1024px) {
            aside {
                display: block;
                position: sticky;
                top: 2rem;
                height: calc(100vh - 4rem);
                overflow-y: auto;
                background: var(--white);
                padding: 1.5rem;
                border-radius: 12px;
                box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
                /* TOC is now in the first column */
                grid-column: 1 / 2; 
            }
            
            /* Custom Scrollbar for TOC */
            aside::-webkit-scrollbar {
                width: 6px;
            }
            aside::-webkit-scrollbar-track {
                background: transparent;
            }
            aside::-webkit-scrollbar-thumb {
                background-color: #cbd5e1;
                border-radius: 3px;
            }
        }

        .toc-title {
            font-size: 0.85rem;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: var(--text-light);
            font-weight: 700;
            margin-bottom: 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 1px solid var(--border);
        }

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

        .toc-nav li {
            margin: 0;
        }

        .toc-nav a {
            display: block;
            padding: 0.4rem 0.7rem; 
            color: var(--text-light);
            font-size: 0.9rem;
            border-radius: 4px;
            text-decoration: none;
        }

        .toc-nav a:hover {
            color: var(--primary-blue);
            background: #f1f5f9;
        }

        .toc-nav a.active {
            color: var(--primary-blue);
            background: #eff6ff;
            font-weight: 600;
        }
        
        /* Indentation for H3 links in TOC */
        .toc-nav .toc-h3 a {
            padding-left: 1.7rem;
            font-size: 0.85rem;
        }


        /* Mobile TOC (Hamburger style simplified for single file) */
        .mobile-toc-toggle {
            display: block;
            background: var(--primary-blue);
            color: white;
            padding: 0.5rem 1rem;
            border-radius: 6px;
            text-align: center;
            margin-bottom: 1rem;
            cursor: pointer;
        }
        
        @media (min-width: 1024px) {
            .mobile-toc-toggle {
                display: none;
            }
        }
        
        /* Helpers */
        .metadata {
            margin-top: 3rem;
            padding-top: 1rem;
            border-top: 1px solid var(--border);
            font-size: 0.8rem;
            color: var(--text-light);
            text-align: center;
        }

        /* Top Banner & Search */
        .top-banner {
            background-color: var(--primary-blue);
            padding: 1rem 2rem;
            display: flex;
            justify-content: center;
            align-items: center;
            width: 100%;
            margin-bottom: 2rem; /* Add space before app-container */
        }

        .search-wrapper {
            position: relative;
            width: 100%;
            max-width: 600px;
        }

        .search-input {
            width: 100%;
            padding: 0.75rem 1rem 0.75rem 2.5rem; /* Left padding for icon space */
            border-radius: 8px;
            border: 1px solid rgba(255, 255, 255, 0.2);
            background: rgba(255, 255, 255, 0.1);
            color: white;
            font-family: 'Inter', sans-serif;
            font-size: 0.95rem;
            outline: none;
            transition: all 0.2s ease;
        }

        .search-input::placeholder {
            color: rgba(255, 255, 255, 0.7);
        }

        .search-input:focus {
            background: rgba(255, 255, 255, 0.2);
            border-color: rgba(255, 255, 255, 0.4);
        }

        /* Simple CSS Search Icon */
        .search-icon {
            position: absolute;
            left: 12px;
            top: 50%;
            transform: translateY(-50%);
            width: 16px;
            height: 16px;
            border: 2px solid rgba(255, 255, 255, 0.7);
            border-radius: 50%;
            pointer-events: none;
        }
        .search-icon::after {
            content: '';
            position: absolute;
            right: -5px;
            bottom: -5px;
            width: 6px;
            height: 2px;
            background: rgba(255, 255, 255, 0.7);
            transform: rotate(45deg);
        }