.nav-menu {
            position: relative;
            z-index: 100;
        }

        /* Верхний уровень меню */
        .menu {
            list-style: none;
            background: linear-gradient(135deg, #3498db, #2c3e50);
            border-radius: 8px;
            display: flex;
            flex-wrap: wrap;
            justify-content: flex-start;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        }

        .menu-item {
            position: relative;
            flex: 1 1 auto;
        }

        .menu-item > a {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 16px 20px;
            color: white;
            text-decoration: none;
            font-weight: 500;
            transition: all 0.3s ease;
            border-right: 1px solid rgba(255, 255, 255, 0.1);
        }

        .menu-item:last-child > a {
            border-right: none;
        }

        .menu-item > a:hover {
            background-color: rgba(255, 255, 255, 0.1);
        }

        .menu-item.active > a {
            background-color: rgba(255, 255, 255, 0.15);
        }

        .menu-item > a i {
            margin-left: 8px;
            font-size: 0.85em;
            transition: transform 0.3s ease;
        }

        .menu-item.active > a i {
            transform: rotate(180deg);
        }

        /* Второй уровень меню */
        .submenu {
            position: absolute;
            top: 100%;
            left: 0;
            width: 220px;
            background-color: white;
            list-style: none;
            border-radius: 0 0 8px 8px;
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.12);
            opacity: 0;
            visibility: hidden;
            transform: translateY(10px);
            transition: all 0.3s ease;
            z-index: 200;
        }

        .menu-item:hover > .submenu,
        .menu-item.active > .submenu {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }

        .submenu-item {
            position: relative;
            border-bottom: 1px solid #f1f1f1;
        }

        .submenu-item:last-child {
            border-bottom: none;
        }

        .submenu-item > a {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 14px 18px;
            color: #2c3e50;
            text-decoration: none;
            font-weight: 500;
            transition: all 0.2s ease;
        }

        .submenu-item > a:hover {
            background-color: #f8f9fa;
            color: #3498db;
            padding-left: 22px;
        }

        .submenu-item > a i {
            color: #95a5a6;
            font-size: 0.8em;
            transition: transform 0.3s ease;
        }

        .submenu-item.active > a i {
            transform: rotate(90deg);
        }

        /* Третий уровень меню */
        .subsubmenu {
            position: absolute;
            top: 0;
            left: 100%;
            width: 220px;
            background-color: white;
            list-style: none;
            border-radius: 0 8px 8px 8px;
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.12);
            opacity: 0;
            visibility: hidden;
            transform: translateX(-10px);
            transition: all 0.3s ease;
            z-index: 300;
        }

        .submenu-item:hover > .subsubmenu,
        .submenu-item.active > .subsubmenu {
            opacity: 1;
            visibility: visible;
            transform: translateX(0);
        }

        .subsubmenu-item > a {
            display: block;
            padding: 12px 18px;
            color: #2c3e50;
            text-decoration: none;
            font-weight: 400;
            transition: all 0.2s ease;
            border-bottom: 1px solid #f1f1f1;
        }

        .subsubmenu-item:last-child > a {
            border-bottom: none;
        }

        .subsubmenu-item > a:hover {
            background-color: #f8f9fa;
            color: #3498db;
            padding-left: 22px;
        }

        /* Адаптация для планшетов */
        @media (max-width: 992px) {
            .menu {
                flex-direction: column;
                border-radius: 8px;
                overflow: hidden;
            }

            .menu-item > a {
                border-right: none;
                border-bottom: 1px solid rgba(255, 255, 255, 0.1);
            }

            .menu-item:last-child > a {
                border-bottom: none;
            }

            .submenu {
                position: static;
                width: 100%;
                opacity: 1;
                visibility: visible;
                transform: none;
                box-shadow: none;
                border-radius: 0;
                background-color: rgba(255, 255, 255, 0.05);
                max-height: 0;
                overflow: hidden;
                transition: max-height 0.4s ease;
            }

            .menu-item.active > .submenu {
                max-height: 500px;
            }

            .submenu-item > a {
                padding-left: 35px;
                color: rgba(255, 255, 255, 0.9);
            }

            .subsubmenu {
                position: static;
                width: 100%;
                opacity: 1;
                visibility: visible;
                transform: none;
                box-shadow: none;
                border-radius: 0;
                background-color: rgba(255, 255, 255, 0.1);
                max-height: 0;
                overflow: hidden;
                transition: max-height 0.4s ease;
            }

            .submenu-item.active > .subsubmenu {
                max-height: 500px;
            }

            .subsubmenu-item > a {
                padding-left: 55px;
                color: rgba(255, 255, 255, 0.85);
            }
        }

        /* Адаптация для мобильных устройств */
        @media (max-width: 576px) {
            .container {
                padding: 15px;
            }

            h1 {
                font-size: 1.5rem;
            }

            .description {
                font-size: 0.95rem;
            }

            .menu-item > a {
                padding: 14px 16px;
                font-size: 0.95rem;
            }

            .submenu-item > a {
                padding: 12px 16px 12px 30px;
            }

            .subsubmenu-item > a {
                padding: 10px 16px 10px 45px;
            }
        }

        /* Информационный блок */
        .info-box {
            margin-top: 40px;
            padding: 20px;
            background-color: #f8f9fa;
            border-radius: 8px;
            border-left: 4px solid #3498db;
        }

        .info-box h3 {
            color: #2c3e50;
            margin-bottom: 10px;
        }

        .info-box p {
            color: #5a6c7d;
            margin-bottom: 15px;
        }

        .features {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            margin-top: 15px;
        }

        .feature {
            background-color: #e3f2fd;
            color: #1565c0;
            padding: 6px 12px;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 500;
        }

        /* Индикатор размера экрана */
        .screen-size {
            position: fixed;
            bottom: 20px;
            right: 20px;
            background-color: #2c3e50;
            color: white;
            padding: 8px 12px;
            border-radius: 20px;
            font-size: 0.85rem;
            font-weight: 500;
            box-shadow: 0 3px 10px rgba(0, 0, 0, 0.2);
            z-index: 500;
        }

        /* Активный элемент подсветка */
        .active-trail {
            background-color: rgba(52, 152, 219, 0.15) !important;
            color: #3498db !important;
        }