* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }

        body {
            background-color: #f5f7fa;
            color: #333;
            line-height: 1.6;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        header {
            background: linear-gradient(135deg, #2c3e50, #4a6491);
            color: white;
            padding: 2rem;
            text-align: center;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }

        header h1 {
            font-size: 2.5rem;
            margin-bottom: 0.5rem;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
        }

        header p {
            font-size: 1.1rem;
            opacity: 0.9;
        }

        .container {
            display: flex;
            flex: 1;
            max-width: 1400px;
            margin: 0 auto;
            width: 100%;
        }

        .sidebar {
            width: 30%;
            background-color: white;
            padding: 2rem;
            box-shadow: 2px 0 10px rgba(0, 0, 0, 0.05);
            overflow-y: auto;
            max-height: calc(100vh - 200px);
        }

        .main-content {
            width: 70%;
            padding: 2rem;
            background-color: #f9fafc;
        }

        .menu-title {
            font-size: 1.5rem;
            margin-bottom: 1.5rem;
            color: #2c3e50;
            padding-bottom: 0.5rem;
            border-bottom: 2px solid #4a6491;
        }

        .documents-menu {
            list-style: none;
        }

        .document-item {
            margin-bottom: 1rem;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
            transition: transform 0.2s, box-shadow 0.2s;
        }

        .document-item:hover {
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }

        .document-link {
            display: flex;
            align-items: center;
            padding: 1rem 1.2rem;
            background-color: white;
            color: #333;
            text-decoration: none;
            border-left: 4px solid #4a6491;
            transition: all 0.2s;
        }

        .document-link:hover {
            background-color: #f0f5ff;
            border-left-color: #e74c3c;
        }

        .document-icon {
            font-size: 1.5rem;
            margin-right: 1rem;
            color: #4a6491;
        }

        .document-info {
            flex: 1;
        }

        .document-title {
            font-weight: 600;
            font-size: 1.1rem;
            margin-bottom: 0.3rem;
        }

        .document-meta {
            font-size: 0.85rem;
            color: #666;
        }

        .preview-container {
            background-color: white;
            border-radius: 10px;
            padding: 2rem;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            height: 100%;
        }

        .preview-title {
            font-size: 1.8rem;
            margin-bottom: 1.5rem;
            color: #2c3e50;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }

        .preview-content {
            margin-bottom: 2rem;
        }

        .preview-section {
            margin-bottom: 2rem;
        }

        .section-title {
            font-size: 1.3rem;
            color: #4a6491;
            margin-bottom: 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 1px solid #eee;
        }

        .toc-list {
            list-style-type: none;
            padding-left: 1rem;
        }

        .toc-list li {
            margin-bottom: 0.7rem;
            padding-left: 1rem;
            position: relative;
        }

        .toc-list li:before {
            content: "▸";
            position: absolute;
            left: 0;
            color: #4a6491;
        }

        .download-btn {
            display: inline-flex;
            align-items: center;
            background: linear-gradient(135deg, #4a6491, #2c3e50);
            color: white;
            padding: 0.8rem 1.5rem;
            border-radius: 6px;
            text-decoration: none;
            font-weight: 600;
            transition: all 0.3s;
            box-shadow: 0 4px 8px rgba(74, 100, 145, 0.3);
        }

        .download-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 12px rgba(74, 100, 145, 0.4);
            background: linear-gradient(135deg, #5a749b, #3c4e60);
        }

        .download-icon {
            margin-right: 0.7rem;
            font-size: 1.2rem;
        }

        .no-preview {
            text-align: center;
            padding: 3rem;
            color: #777;
            font-style: italic;
        }

        footer {
            background-color: #2c3e50;
            color: white;
            padding: 2.5rem 2rem;
            text-align: center;
            margin-top: auto;
        }

        .footer-content {
            max-width: 800px;
            margin: 0 auto;
        }

        .footer-title {
            font-size: 1.5rem;
            margin-bottom: 1rem;
            color: #ecf0f1;
        }

        .footer-description {
            margin-bottom: 1.5rem;
            line-height: 1.6;
            font-size: 1.1rem;
        }

        .email-link {
            color: #3498db;
            font-weight: 600;
            text-decoration: none;
            border-bottom: 1px dashed #3498db;
            transition: color 0.2s;
        }

        .email-link:hover {
            color: #5dade2;
            border-bottom-style: solid;
        }

        .copyright {
            margin-top: 2rem;
            padding-top: 1.5rem;
            border-top: 1px solid #3a506b;
            font-size: 0.9rem;
            color: #bdc3c7;
        }

        @media (max-width: 992px) {
            .container {
                flex-direction: column;
            }

            .sidebar,
            .main-content {
                width: 100%;
            }

            .sidebar {
                max-height: none;
                border-right: none;
                border-bottom: 1px solid #eee;
            }

            header h1 {
                font-size: 2rem;
            }
        }

        .selected {
            background-color: #f0f5ff;
            border-left-color: #e74c3c;
        }

        /* Стили для счетчика посетителей */
        .visit-stats {
            margin-top: 2rem;
            padding: 1rem;
            background: rgba(255, 255, 255, 0.1);
            border-radius: 8px;
            font-size: 0.9rem;
            animation: fadeIn 0.5s ease;
        }

        .visit-stats:hover {
            background: rgba(255, 255, 255, 0.15);
        }

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

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        /* Анимация для уведомлений */
        @keyframes slideIn {
            from {
                transform: translateX(100%);
                opacity: 0;
            }

            to {
                transform: translateX(0);
                opacity: 1;
            }
        }

        @keyframes slideOut {
            from {
                transform: translateX(0);
                opacity: 1;
            }

            to {
                transform: translateX(100%);
                opacity: 0;
            }
        }