/* ============================================
           Shared Variables (Same as index)
           ============================================ */
        :root {
            --color-bg-primary: #FAF7F2;
            --color-bg-secondary: #F5F5F0;
            --color-text-primary: #2C2C2C;
            --color-text-secondary: #6B6B6B;
            --color-accent-terracotta: #C4A484;
            --color-accent-sage: #8B9A7D;
            --color-accent-classic-blue: #4A5568;
            --color-border: rgba(0, 0, 0, 0.06);
            
            --font-serif: 'Cormorant Garamond', Georgia, serif;
            --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            
            --space-xs: 0.5rem;
            --space-sm: 1rem;
            --space-md: 2rem;
            --space-lg: 4rem;
            --space-xl: 8rem;
            
            --shadow-soft: 0 10px 30px -15px rgba(0, 0, 0, 0.08);
            --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

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

        body {
            font-family: var(--font-sans);
            background-color: var(--color-bg-primary);
            color: var(--color-text-primary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            overflow-x: hidden;
            position: relative;
            min-height: 100vh;
        }

        /* Background image with overlay */
        body::before {
            content: '';
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-image: url('https://cstupic.creaconception.moe/api');
            background-size: cover;
            background-position: center;
            background-repeat: no-repeat;
            z-index: -2;
            filter: blur(2px);
        }

        /* Overlay to blend background with theme colors */
        body::after {
            content: '';
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(250, 247, 242, 0.7); /* Using primary background color with transparency */
            z-index: -1;
        }

        /* ============================================
           Layout Structure
           ============================================ */
        .app-container {
            display: flex;
            min-height: 100vh;
        }

        /* ============================================
           Mobile Header (Visible only on mobile)
           ============================================ */
        .mobile-header {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            padding: var(--space-sm);
            background: rgba(250, 247, 242, 0.95);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--color-border);
            justify-content: space-between;
            align-items: center;
        }

        .mobile-logo {
            font-family: var(--font-serif);
            font-size: 1.25rem;
            font-weight: 600;
            text-decoration: none;
            color: var(--color-text-primary);
        }

        .menu-toggle {
            background: none;
            border: none;
            cursor: pointer;
            padding: var(--space-xs);
            display: flex;
            flex-direction: column;
            gap: 5px;
            z-index: 1001;
        }

        .menu-toggle span {
            width: 24px;
            height: 1.5px;
            background: var(--color-text-primary);
            transition: var(--transition-smooth);
        }

        /* ============================================
           Sidebar Navigation
           ============================================ */
        .sidebar {
            width: 320px;
            background: rgba(245, 245, 240, 0.2); /* 80% transparency */
            backdrop-filter: blur(10px); /* Blur effect */
            border-right: 1px solid var(--color-border);
            padding: var(--space-lg) var(--space-md);
            position: fixed;
            height: 100vh;
            overflow-y: auto;
            display: flex;
            flex-direction: column;
            z-index: 100;
        }

        .sidebar-logo {
            font-family: var(--font-serif);
            font-size: 1.5rem;
            font-weight: 600;
            text-decoration: none;
            color: var(--color-text-primary);
            margin-bottom: var(--space-lg);
            display: flex;
            align-items: center;
            gap: var(--space-xs);
        }

        .sidebar-logo-mark {
            width: 32px;
            height: 32px;
            background: linear-gradient(135deg, var(--color-accent-terracotta), var(--color-accent-sage));
            border-radius: 8px;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 0.9rem;
        }

        .category-nav {
            list-style: none;
            flex: 1;
        }

        .category-item {
            margin-bottom: var(--space-xs);
        }

        .category-link {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: var(--space-sm) var(--space-md);
            text-decoration: none;
            color: var(--color-text-secondary);
            border-radius: 8px;
            transition: var(--transition-smooth);
            position: relative;
            font-size: 0.95rem;
        }

        .category-link:hover,
        .category-link:focus-visible {
            background: rgba(196, 164, 132, 0.1);
            color: var(--color-text-primary);
            outline: none;
        }

        .category-link.active {
            background: rgba(255, 255, 255, 0.2); /* 80% transparency */
            backdrop-filter: blur(5px); /* Blur effect */
            color: var(--color-text-primary);
            box-shadow: var(--shadow-soft);
            font-weight: 500;
        }

        .category-link.active::before {
            content: '';
            position: absolute;
            left: 0;
            top: 50%;
            transform: translateY(-50%);
            width: 3px;
            height: 20px;
            background: var(--color-accent-terracotta);
            border-radius: 0 2px 2px 0;
        }

        .category-count {
            font-size: 0.75rem;
            color: var(--color-text-secondary);
            background: rgba(250, 247, 242, 0.2); /* 80% transparency */
            backdrop-filter: blur(5px); /* Blur effect */
            padding: 2px 8px;
            border-radius: 12px;
            transition: var(--transition-smooth);
        }

        .category-link.active .category-count {
            background: var(--color-accent-terracotta);
            color: white;
        }

        .sidebar-footer {
            margin-top: auto;
            padding-top: var(--space-md);
            border-top: 1px solid var(--color-border);
            font-size: 0.8rem;
            color: var(--color-text-secondary);
        }

        /* ============================================
           Main Content Area
           ============================================ */
        .main-content {
            margin-left: 320px;
            flex: 1;
            padding: var(--space-lg);
            min-height: 100vh;
            background: rgba(250, 247, 242, 0.2); /* 80% transparency */
            backdrop-filter: blur(10px); /* Blur effect */
        }

        .content-header {
            margin-bottom: var(--space-lg);
            padding-bottom: var(--space-md);
            border-bottom: 1px solid var(--color-border);
        }

        .content-title {
            font-family: var(--font-serif);
            font-size: 2.5rem;
            font-weight: 400;
            margin-bottom: var(--space-xs);
            color: var(--color-text-primary);
        }

        .content-subtitle {
            color: var(--color-text-secondary);
            font-size: 1rem;
            font-weight: 300;
        }

        /* ============================================
           Content Sections
           ============================================ */
        .content-section {
            display: none;
            animation: fadeIn 0.4s ease;
        }

        .content-section.active {
            display: block;
        }

        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .link-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: var(--space-md);
        }

        .link-card {
            background: rgba(255, 255, 255, 0.2); /* 80% transparency */
            backdrop-filter: blur(10px); /* Blur effect */
            border: 1px solid var(--color-border);
            border-radius: 10px;
            padding: var(--space-md);
            text-decoration: none;
            color: inherit;
            transition: var(--transition-smooth);
            position: relative;
            overflow: hidden;
        }

        .link-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 3px;
            background: var(--color-accent-terracotta);
            transform: scaleX(0);
            transition: transform 0.3s ease;
        }

        .link-card:hover,
        .link-card:focus-visible {
            transform: translateY(-2px);
            box-shadow: var(--shadow-soft);
            border-color: rgba(196, 164, 132, 0.3);
            outline: none;
        }

        .link-card:hover::before,
        .link-card:focus-visible::before {
            transform: scaleX(1);
        }

        .link-header {
            display: flex;
            justify-content: space-between;
            align-items: start;
            margin-bottom: var(--space-sm);
        }

        .link-icon {
            width: 40px;
            height: 40px;
            background: rgba(245, 245, 240, 0.2); /* 80% transparency */
            backdrop-filter: blur(5px); /* Blur effect */
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.25rem;
            transition: var(--transition-smooth);
        }

        .link-card:hover .link-icon {
            background: var(--color-accent-terracotta);
            color: white;
            transform: scale(1.1);
        }

        .link-arrow {
            opacity: 0;
            transform: translateX(-10px);
            transition: var(--transition-smooth);
            color: var(--color-accent-terracotta);
        }

        .link-card:hover .link-arrow {
            opacity: 1;
            transform: translateX(0);
        }

        .link-title {
            font-family: var(--font-serif);
            font-size: 1.25rem;
            margin-bottom: var(--space-xs);
            color: var(--color-text-primary);
        }

        .link-url {
            font-size: 0.75rem;
            color: var(--color-accent-terracotta);
            text-transform: uppercase;
            letter-spacing: 0.05em;
            margin-bottom: var(--space-xs);
            font-family: monospace;
        }

        .link-description {
            font-size: 0.9rem;
            color: var(--color-text-secondary);
            line-height: 1.5;
            font-weight: 300;
        }

        .link-meta {
            margin-top: var(--space-sm);
            padding-top: var(--space-sm);
            border-top: 1px solid var(--color-border);
            display: flex;
            gap: var(--space-sm);
            font-size: 0.75rem;
            color: var(--color-text-secondary);
        }

        .meta-tag {
            background: rgba(245, 245, 240, 0.2); /* 80% transparency */
            backdrop-filter: blur(5px); /* Blur effect */
            padding: 2px 8px;
            border-radius: 4px;
        }

        /* ============================================
           Responsive Design
           ============================================ */
        @media (max-width: 968px) {
            .mobile-header {
                display: flex;
            }

            .sidebar {
                transform: translateX(-100%);
                transition: transform 0.3s ease;
                width: 280px;
                padding-top: calc(var(--space-lg) + 60px);
            }

            .sidebar.open {
                transform: translateX(0);
            }

            .main-content {
                margin-left: 0;
                padding-top: calc(var(--space-lg) + 60px);
                background: rgba(250, 247, 242, 0.2); /* 80% transparency */
                backdrop-filter: blur(10px); /* Blur effect */
            }

            .overlay {
                display: none;
                position: fixed;
                top: 0;
                left: 0;
                right: 0;
                bottom: 0;
                background: rgba(0, 0, 0, 0.3);
                z-index: 99;
                backdrop-filter: blur(4px);
            }

            .overlay.active {
                display: block;
            }

            .content-title {
                font-size: 2rem;
            }

            .link-grid {
                grid-template-columns: 1fr;
            }
        }

        /* Focus visible */
        *:focus-visible {
            outline: 2px solid var(--color-accent-terracotta);
            outline-offset: 2px;
        }

        /* Reduced motion */
        @media (prefers-reduced-motion: reduce) {
            * {
                transition-duration: 0.01ms !important;
                animation-duration: 0.01ms !important;
            }
        }

        /* ============================================
           Other Styles
           ============================================ */

        a, a:link, a:visited, a:hover, a:active, a:focus {
            color: inherit;
        }

        .redirect {
            transition: color 0.3s ease; /* 渐变动画 */
        }

        .redirect:hover {
            color: #C4A484; /* 悬停颜色 */
        }