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

        body {
            font-family: 'Roboto', sans-serif;
            background: linear-gradient(135deg, #FFF8E1 0%, #FFE0B2 100%);
            color: #2C3E50;
            line-height: 1.7;
            overflow-x: hidden;
        }

        #menu {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(20px);
            z-index: 1000;
            padding: 15px 0;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
            transition: all 0.3s ease;
        }

        .menu-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            max-width: 1400px;
            margin: 0 auto;
            padding: 0 30px;
        }

        .logo {
            font-size: 28px;
            font-weight: 700;
            color: #E74C3C;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .logo i {
            font-size: 32px;
        }

        .vietnam-title {
            font-family: 'Playfair Display', serif;
            font-size: 32px;
            font-weight: 700;
            color: #27AE60;
            margin: 0;
            letter-spacing: 2px;
        }

        .hamburger {
            font-size: 28px;
            cursor: pointer;
            color: #2C3E50;
            background: none;
            border: none;
            padding: 5px;
            transition: transform 0.3s ease;
        }

        .hamburger:hover {
            transform: rotate(90deg);
        }

        .sidebar {
            position: fixed;
            top: 0;
            left: -300px;
            width: 300px;
            height: 100vh;
            background: linear-gradient(180deg, #FFF8E1 0%, #FFE0B2 100%);
            transition: left 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            z-index: 1001;
            box-shadow: 4px 0 20px rgba(0, 0, 0, 0.15);
        }

        .sidebar.active {
            left: 0;
        }

        .sidebar-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 25px 30px;
            background: linear-gradient(135deg, #E74C3C, #C0392B);
            color: white;
        }

        .sidebar-header h3 {
            font-family: 'Playfair Display', serif;
            font-size: 24px;
        }

        .close-btn {
            background: none;
            border: none;
            font-size: 28px;
            cursor: pointer;
            color: white;
            transition: transform 0.3s ease;
        }

        .close-btn:hover {
            transform: scale(1.2);
        }

        .sidebar ul {
            list-style: none;
            padding: 30px 0;
            margin: 0;
        }

        .sidebar li {
            padding: 18px 30px;
            border-bottom: 1px solid rgba(231, 76, 60, 0.1);
            transition: all 0.3s ease;
        }

        .sidebar li:hover {
            background: rgba(231, 76, 60, 0.1);
            padding-left: 40px;
        }

        .sidebar a {
            text-decoration: none;
            color: #2C3E50;
            font-weight: 500;
            font-size: 16px;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .sidebar a i {
            width: 20px;
            color: #E74C3C;
        }

        .welcome-box {
            position: absolute;
            bottom: 30px;
            left: 30px;
            right: 30px;
            background: linear-gradient(135deg, #27AE60, #2ECC71);
            color: white;
            padding: 20px;
            text-align: center;
            border-radius: 15px;
            font-size: 14px;
            font-weight: 500;
            animation: slideUp 1s ease-out 0.5s both;
            box-shadow: 0 8px 25px rgba(39, 174, 96, 0.3);
        }

        @keyframes slideUp {
            from {
                opacity: 0;
                transform: translateY(20px);
            }

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

        #banner {
            position: relative;
            width: 100%;
            height: 600px;
            overflow: hidden;
            margin-top: 80px;
        }

        .slideshow {
            position: relative;
            width: 100%;
            height: 100%;
        }

        .slide {
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            opacity: 0;
            transition: opacity 1.2s ease-in-out;
        }

        .slide.active {
            opacity: 1;
        }

        .slide img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            filter: brightness(0.8);
        }

        .slide::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: linear-gradient(rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.1));
        }

        .nav-btn {
            position: absolute;
            top: 50%;
            transform: translateY(-50%);
            background: linear-gradient(135deg, rgba(231, 76, 60, 0.8), rgba(192, 57, 43, 0.8));
            color: white;
            border: none;
            padding: 15px 20px;
            cursor: pointer;
            font-size: 20px;
            transition: all 0.3s ease;
            border-radius: 50%;
            width: 50px;
            height: 50px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .nav-btn:hover {
            background: linear-gradient(135deg, #E74C3C, #C0392B);
            transform: translateY(-50%) scale(1.1);
        }

        .prev {
            left: 20px;
        }

        .next {
            right: 20px;
        }

        .dots {
            position: absolute;
            bottom: 40px;
            left: 50%;
            transform: translateX(-50%);
            display: flex;
            gap: 10px;
        }

        .dot {
            width: 15px;
            height: 15px;
            border-radius: 50%;
            background-color: rgba(255, 255, 255, 0.5);
            cursor: pointer;
            transition: all 0.3s ease;
        }

        .dot.active {
            background-color: #E74C3C;
            transform: scale(1.2);
        }

        #title {
            display: flex;
            max-width: 1400px;
            margin: 60px auto;
            padding: 0 30px;
            gap: 50px;
        }

        .title-box {
            flex: 1;
            background: white;
            padding: 40px;
            border-radius: 20px;
            box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
            transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            position: relative;
            overflow: hidden;
        }

        .title-box::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 5px;
            background: linear-gradient(90deg, #E74C3C, #27AE60);
        }

        .title-box:hover {
            transform: translateY(-10px);
            box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
        }

        .title-box h2 {
            font-family: 'Playfair Display', serif;
            color: #E74C3C;
            font-size: 28px;
            margin-bottom: 25px;
            text-align: center;
        }

        .title-box p {
            margin-bottom: 20px;
            text-align: justify;
        }

        .title-box a {
            display: inline-block;
            margin-top: 20px;
            color: white;
            text-decoration: none;
            font-weight: 500;
            padding: 12px 25px;
            background: linear-gradient(135deg, #27AE60, #2ECC71);
            border-radius: 30px;
            transition: all 0.3s ease;
            text-align: center;
        }

        .title-box a:hover {
            background: linear-gradient(135deg, #2ECC71, #27AE60);
            transform: translateY(-2px);
        }

        .video-container {
            flex: 1;
            display: flex;
            flex-direction: column;
        }

        .video-container iframe {
            width: 100%;
            height: 280px;
            border-radius: 15px;
            margin-top: 25px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        }

        #content {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            grid-template-rows: auto auto;
            gap: 30px;
            max-width: 1400px;
            margin: 60px auto;
            padding: 0 30px;
        }

        .content-box {
            background: white;
            padding: 40px 30px;
            border-radius: 20px;
            box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
            transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .content-box::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 4px;
            background: linear-gradient(90deg, #E74C3C, #27AE60);
        }

        .content-box:hover {
            transform: translateY(-10px) scale(1.02);
            box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
        }

        .content-box i {
            font-size: 48px;
            color: #E74C3C;
            margin-bottom: 20px;
        }

        .content-box h2 {
            font-family: 'Playfair Display', serif;
            color: #27AE60;
            font-size: 24px;
            margin-bottom: 15px;
        }

        .content-box h3 {
            color: #E74C3C;
            font-size: 20px;
            margin-bottom: 20px;
        }

        .content-box p {
            margin-bottom: 25px;
        }

        .content-box a {
            display: inline-block;
            color: white;
            text-decoration: none;
            font-weight: 500;
            padding: 12px 25px;
            background: linear-gradient(135deg, #E74C3C, #C0392B);
            border-radius: 30px;
            transition: all 0.3s ease;
        }

        .content-box a:hover {
            background: linear-gradient(135deg, #C0392B, #E74C3C);
            transform: translateY(-2px);
        }

        #footer {
            background: linear-gradient(135deg, #2C3E50 0%, #34495E 100%);
            color: white;
            padding: 50px 30px 30px;
            text-align: center;
            margin-top: 80px;
            position: relative;
        }

        #footer::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 5px;
            background: linear-gradient(90deg, #E74C3C, #27AE60);
        }

        .footer-info {
            max-width: 1400px;
            margin: 0 auto;
        }

        .footer-info p {
            margin-bottom: 15px;
            opacity: 0.9;
        }

        .footer-links {
            margin: 30px 0;
        }

        .footer-links a {
            color: #E74C3C;
            text-decoration: none;
            margin: 0 15px;
            font-weight: 500;
            transition: all 0.3s ease;
            display: inline-flex;
            align-items: center;
            gap: 5px;
        }

        .footer-links a:hover {
            color: white;
            transform: translateY(-2px);
        }

        .footer-links i {
            font-size: 16px;
        }

        @media (max-width: 768px) {
            .menu-container {
                padding: 0 20px;
            }

            .vietnam-title {
                font-size: 24px;
            }

            #title {
                flex-direction: column;
                gap: 30px;
            }

            #content {
                grid-template-columns: 1fr;
                gap: 20px;
                padding: 0 20px;
            }

            .sidebar {
                width: 100%;
                left: -100%;
            }

            #banner {
                height: 400px;
            }
        }
        /* NÚT LÊN ĐẦU TRANG */
        #backToTop {
            position: fixed;
            bottom: 30px;
            right: 30px;
            background-color: #ed2809;
            color: white;
            border: none;
            border-radius: 50%;
            width: 50px;
            height: 50px;
            font-size: 24px;
            cursor: pointer;
            box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
            display: none;
            transition: background-color 0.3s ease, transform 0.3s ease;
            z-index: 999;
        }

        #backToTop:hover {
            background-color: #f5f505;
            color: #000;
            transform: scale(1.1);
        }