/* --- CSS VARIABLES --- */
        :root {
            --primary-color: #0066cc;
            --primary-dark: #004494;
            --text-dark: #222;
            --text-gray: #555;
            --bg-gray: #f9f9f9;
            --white: #fff;
            --radius: 12px;
            --shadow: 0 8px 25px rgba(0,0,0,0.08);
        }

        /* --- GLOBAL RESET --- */
        #vvh-profile {
            font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
            color: var(--text-dark);
            line-height: 1.6;
            background-color: #fff;
            width: 100%;
            box-sizing: border-box;
        }
        #vvh-profile * { box-sizing: border-box; }
        #vvh-profile a { text-decoration: none; transition: 0.3s; margin: 5px; }
        #vvh-profile img { max-width: 100%; height: auto; }

        /* --- UTILITIES --- */
        .vvh-container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }
        .vvh-section { padding: 70px 0; border-bottom: 1px solid #f0f0f0; }
        .vvh-section.bg-gray { background-color: var(--bg-gray); border: none; }
        
        /* HEADING STYLES - Nổi bật hơn */
        .vvh-heading-main {
            font-size: 2.2rem;
            font-weight: 800;
            text-align: center;
            margin-bottom: 50px;
            color: var(--text-dark);
            position: relative;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }
        .vvh-heading-main::after {
            content: ''; display: block; width: 60px; height: 5px; 
            background: var(--primary-color); margin: 15px auto 0; border-radius: 3px;
        }
        
        .vvh-heading-sub {
            font-size: 1.8rem;
            color: var(--primary-color);
            margin-top: 0;
            margin-bottom: 20px;
            font-weight: 700;
            display: flex;
            align-items: center;
        }
        .vvh-heading-sub::before {
            content: ''; display: inline-block; width: 6px; height: 25px;
            background: var(--primary-color); margin-right: 15px; border-radius: 4px;
        }

        /* BUTTONS */
        .vvh-btn {
            display: inline-flex; align-items: center; justify-content: center; gap: 8px;
            padding: 12px 28px;
            background-color: var(--primary-color);
            color: var(--white) !important;
            border-radius: 50px;
            font-weight: 600;
            border: 2px solid var(--primary-color);
            cursor: pointer;
        }
        .vvh-btn:hover { background-color: var(--primary-dark); transform: translateY(-2px); }
        .vvh-btn.outline { background: transparent; color: var(--primary-color) !important; }
        .vvh-btn.outline:hover { background: var(--primary-color); color: var(--white) !important; }

        /* --- 1. HERO SECTION --- */
        .vvh-hero {
            text-align: center;
            padding: 80px 20px 100px;
            background: linear-gradient(135deg, #0052cc 0%, #003380 100%);
            color: white;
            border-radius: 0 0 50% 50% / 30px;
        }
        .vvh-avatar {
            width: 180px; height: 180px; border-radius: 50%;
            border: 5px solid rgba(255,255,255,0.4);
            object-fit: cover; margin-bottom: 20px; background: #fff;
            box-shadow: 0 10px 30px rgba(0,0,0,0.2);
        }
        .vvh-hero h1 { font-size: 3.2rem; margin: 0; color: white; font-weight: 800; }
        .vvh-hero .role { font-size: 1.25rem; color: #e6f0ff; margin: 10px 0 25px; }

        /* --- 2. ABOUT & INFO GRID --- */
        .vvh-about-layout { display: grid; grid-template-columns: 1.3fr 1.1fr; gap: 50px; }
        .vvh-text p { margin-bottom: 1.5em; text-align: justify; color: #444; font-size: 1.05rem; }
        
        /* INFO BOX STYLE - Căn chỉnh đẹp */
        .vvh-info-box {
            background: white; padding: 35px;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            border: 1px solid #eee;
        }
        .vvh-info-row {
            display: flex;
            justify-content: space-between;
            padding: 12px 0;
            border-bottom: 1px dashed #e0e0e0;
            font-size: 1rem;
        }
        .vvh-info-row:last-child { border-bottom: none; }
        .vvh-label { color: #595959; font-weight: 500; min-width: 100px; }
        .vvh-value { color: var(--text-dark); font-weight: 700; text-align: right; }
        .vvh-value a { color: var(--primary-color); }

        /* --- 3. WEBSITE ECOSYSTEM (NEW) --- */
        .vvh-web-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 30px; margin-top: 20px; }
        .vvh-web-card {
            background: white; padding: 25px; border-radius: var(--radius);
            border: 1px solid #e0e0e0; display: flex; align-items: center; gap: 20px;
            transition: 0.3s;
        }
        .vvh-web-card:hover { border-color: var(--primary-color); transform: translateY(-5px); box-shadow: var(--shadow); }
        .vvh-web-icon { font-size: 2.5rem; }
        .vvh-web-content h4 { margin: 0 0 5px; font-size: 1.2rem; color: var(--primary-color); }
        .vvh-web-content span { font-size: 0.9rem; color: #666; }

 /* --- 4. TIMELINE (UPDATED DETAILED) --- */
        .vvh-timeline { position: relative; border-left: 3px solid #e0e0e0; margin-left: 10px; padding-left: 35px; }
        .vvh-timeline-item { margin-bottom: 50px; position: relative; }
        .vvh-timeline-item::before {
            content: ''; position: absolute; left: -45px; top: 5px;
            width: 18px; height: 18px; background: var(--primary-color);
            border-radius: 50%; border: 4px solid #fff; box-shadow: 0 0 0 1px #ccc;
        }
        .vvh-time { 
            background: #eef6ff; color: var(--primary-color); 
            padding: 5px 15px; border-radius: 4px; font-weight: bold; font-size: 0.9rem; 
            display: inline-block; margin-bottom: 10px;
        }
        .vvh-timeline-item h3 { margin: 0 0 5px; font-size: 1.4rem; color: var(--text-dark); }
        .vvh-company { font-size: 1.1rem; color: #666; font-weight: 500; margin-bottom: 15px; display: block; }
        
        /* --- 5. CERTIFICATES & RESOURCES (Grid Fix) --- */
        .vvh-grid-equal { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 25px; }
        .vvh-card {
            background: white; padding: 30px; border-radius: var(--radius);
            box-shadow: var(--shadow); display: flex; flex-direction: column;
            text-align: center; height: 100%; border: 1px solid #eee;
            transition: 0.3s;
        }
        .vvh-card:hover { transform: translateY(-5px); border-color: var(--primary-color); }
        .vvh-card-title { font-weight: 700; margin-bottom: 5px; color: var(--text-dark); }
        .vvh-card-sub { font-size: 0.9rem; color: #595959; margin-bottom: 20px; }
        .vvh-card-btn { margin-top: auto; color: var(--primary-color); font-weight: bold; font-size: 0.9rem; }
		
		/* --- BỔ SUNG: TAG CLOUD LINKS --- */
    .vvh-tag-box {
        text-align: center;
        margin-bottom: 50px;
    }
    .vvh-tag-label {
        display: inline-block;
        background: var(--primary-color);
        color: white;
        padding: 8px 20px;
        font-weight: 700;
        border-radius: 6px;
        margin-bottom: 25px;
        text-transform: uppercase;
        font-size: 0.9rem;
        letter-spacing: 0.05em;
    }
    .vvh-tag-container {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 12px;
    }
    .vvh-link-tag {
        display: inline-block;
        padding: 10px 20px;
        background: white;
        border: 1px solid #e5e7eb;
        border-radius: 8px;
        color: var(--text-gray);
        font-weight: 600;
        font-size: 0.95rem;
        transition: all 0.2s ease;
        box-shadow: 0 2px 5px rgba(0,0,0,0.03);
    }
    .vvh-link-tag:hover {
        background: var(--primary-color);
        color: #fff;
        border-color: var(--primary-color);
        transform: translateY(-3px);
        box-shadow: 0 5px 15px rgba(0,102,204,0.25);
    }

        /* --- 6. SOCIAL FOOTER (COLORS & ICONS) --- */
        .vvh-footer { background: #1a1a1a; padding: 60px 0; color: #fff; text-align: center; }
        .vvh-social-grid { display: flex; justify-content: center; gap: 15px; flex-wrap: wrap; margin-top: 30px; }
        
        .social-btn {
            display: flex; align-items: center; gap: 10px;
            padding: 10px 25px; border-radius: 6px;
            color: white !important; font-weight: 600; font-size: 0.95rem;
            transition: 0.3s; border: none;
        }
        .social-btn:hover { filter: brightness(1.1); transform: translateY(-2px); }
        .social-btn svg { width: 18px; height: 18px; fill: currentColor; }
        
        /* Brand Colors */
        .btn-fb { background-color: #1877F2; }
        .btn-in { background-color: #0A66C2; }
        .btn-yt { background-color: #FF0000; }
        .btn-sp { background-color: #1DB954; color: #000!important; } /* Spotify Green */
        .btn-web { background-color: #F57C00; } /* Community Orange */

        @media (max-width: 768px) {
            .vvh-about-layout, .vvh-web-grid { grid-template-columns: 1fr; }
            .vvh-hero h1 { font-size: 2.2rem; }
            .vvh-heading-sub::before { display: none; }
            .vvh-heading-sub { text-align: center; display: block; }
        }


 :root {
            --vvh-primary: #0d6efd;
            --vvh-primary-dark: #0a58ca;
            --vvh-bg-light: #f8f9fa;
            --vvh-text-dark: #212529;
            --vvh-text-gray: #6c757d;
            --vvh-border: #dee2e6;
            --vvh-shadow: 0 4px 15px rgba(0,0,0,0.05);
            --vvh-radius: 8px;
            --vvh-sidebar-width: 380px;
        }

        /* Wrapper chính */
        .vvh-academy-wrapper {
            font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
            margin: 2rem 0;
            background: #fff;
            color: var(--vvh-text-dark);
            line-height: 1.6;
        }
        
        .vvh-academy-wrapper * { box-sizing: border-box; }

        /* Header Area */
        .vvh-header-section {
            text-align: center;
            margin-bottom: 2rem;
            padding: 0 1rem;
        }
        .vvh-main-title {
            font-size: 2.2rem;
            font-weight: 800;
            margin-bottom: 1rem;
            color: var(--vvh-text-dark);
            line-height: 1.2;
        }
        .vvh-intro-text {
            max-width: 800px;
            margin: 0 auto 1.5rem;
            color: var(--vvh-text-gray);
            font-size: 1.1rem;
        }
        .vvh-cta-btn {
            display: inline-block;
            background: var(--vvh-primary);
            color: #fff;
            padding: 10px 25px;
            border-radius: 50px;
            text-decoration: none;
            font-weight: 600;
            transition: all 0.3s;
            box-shadow: 0 4px 10px rgba(13, 110, 253, 0.3);
        }
        .vvh-cta-btn:hover {
            background: var(--vvh-primary-dark);
            color: #fff;
            transform: translateY(-2px);
        }
		
		/* --- NÚT BACK HOME --- */
        .vvh-back-home {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            text-decoration: none;
            color: var(--vvh-text-gray);
            font-weight: 600;
            font-size: 0.95rem;
            transition: all 0.2s;
            margin-bottom: 10px;
            padding: 8px 15px;
            border-radius: 50px;
            background: #fff;
            border: 1px solid transparent;
        }
        .vvh-back-home:hover {
            color: var(--vvh-primary);
            background: #f0f2f5;
            border-color: #dee2e6;
            transform: translateX(-3px); /* Hiệu ứng lùi nhẹ */
        }

        /* Grid Layout */
        .vvh-academy-container {
            display: grid;
            grid-template-columns: 1fr var(--vvh-sidebar-width);
            gap: 2rem;
            max-width: 1400px;
            margin: 0 auto;
        }

        /* Cột trái: Video Player */
        .vvh-player-section {
            display: flex;
            flex-direction: column;
        }

        .vvh-video-wrapper {
            position: relative;
            padding-bottom: 56.25%; /* 16:9 Aspect Ratio */
            background: #000;
            border-radius: var(--vvh-radius);
            overflow: hidden;
            box-shadow: var(--vvh-shadow);
            margin-bottom: 1.5rem;
        }
        .vvh-video-wrapper iframe {
            position: absolute; top:0; left:0; width:100%; height:100%; border:0;
        }

        /* Video Controls & Title */
        .vvh-playing-info {
            border-bottom: 1px solid var(--vvh-border);
            padding-bottom: 1rem;
            margin-bottom: 1.5rem;
        }
        .vvh-now-playing-label {
            font-size: 0.9rem;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: var(--vvh-primary);
            font-weight: 700;
            margin-bottom: 0.5rem;
            display: block;
        }
        .vvh-current-title {
            font-size: 1.5rem;
            font-weight: 700;
            margin: 0 0 1rem;
            line-height: 1.3;
        }
        .vvh-controls {
            display: flex;
            gap: 10px;
            align-items: center;
            flex-wrap: wrap;
        }
        .vvh-control-btn {
            background: var(--vvh-primary);
            border: 1px solid var(--vvh-border);
            padding: 8px 15px;
            border-radius: 6px;
            cursor: pointer;
            font-size: 0.9rem;
            transition: 0.2s;
            display: flex;
            align-items: center;
            gap: 5px;
        }
        .vvh-control-btn:hover { background: #e9ecef; }
        .vvh-control-btn:disabled { opacity: 0.5; cursor: not-allowed; }

        .vvh-autoplay-toggle {
            display: flex;
            align-items: center;
            gap: 8px;
            margin-left: auto;
            font-size: 0.9rem;
            cursor: pointer;
            user-select: none;
        }
        .vvh-toggle-switch {
            position: relative; width: 40px; height: 20px; background: #ccc; border-radius: 20px; transition: 0.3s;
        }
        .vvh-toggle-switch::after {
            content:''; position: absolute; left: 2px; top: 2px; width: 16px; height: 16px; background: #fff; border-radius: 50%; transition: 0.3s;
        }
        .vvh-autoplay-active .vvh-toggle-switch { background: var(--vvh-primary); }
        .vvh-autoplay-active .vvh-toggle-switch::after { left: 22px; }


        /* Cột phải: Playlist Sidebar */
        .vvh-sidebar-section {
            background: var(--vvh-bg-light);
            border-radius: var(--vvh-radius);
            padding: 1.5rem;
            height: fit-content;
            max-height: 100vh;
            position: sticky;
            top: 20px;
            display: flex;
            flex-direction: column;
            border: 1px solid var(--vvh-border);
        }

        .vvh-search-box {
            position: relative;
            margin-bottom: 1rem;
        }
        .vvh-search-input {
            width: 100%;
            padding: 12px 40px 12px 15px;
            border: 1px solid var(--vvh-border);
            border-radius: 50px;
            font-size: 1rem;
            outline: none;
            transition: border 0.3s;
        }
        .vvh-search-input:focus { border-color: var(--vvh-primary); box-shadow: 0 0 0 3px rgba(13,110,253,0.1); }
        .vvh-search-icon {
            position: absolute; right: 15px; top: 50%; transform: translateY(-50%); color: var(--vvh-text-gray);
        }
								
		/* DISCLAIMER CSS - Định dạng phần miễn trừ trách nhiệm */
.vvh-disclaimer-section {
    margin-top: 2rem;       /* Cách phần trên 2rem */
    padding-top: 1rem;      /* Khoảng đệm bên trong */
    border-top: 1px solid #eee; /* Đường kẻ mờ ngăn cách */
    font-size: 0.85rem;     /* Chữ nhỏ hơn bình thường */
    color: #888;            /* Màu chữ xám nhạt */
    text-align: center;     /* Căn giữa */
    font-style: italic;     /* Chữ nghiêng */
}
.vvh-disclaimer-section strong {
    color: #555;            /* Màu chữ đậm cho phần tiêu đề */
    font-style: normal;     /* Chữ đậm không nghiêng */
}						

        /* Tabs Topic */
.vvh-topics-nav {
    display: flex;
    gap: 10px;
    overflow-x: auto;
    overflow-y: hidden; /* Chặn cuộn dọc */
    padding: 5px 5px 15px 5px; /* Tăng padding đáy để thanh cuộn không che nút */
    margin-bottom: 1rem;
    scrollbar-width: thin;
    flex-wrap: nowrap; /* Bắt buộc 1 hàng ngang */
    align-items: center;
    min-height: 60px; /* QUAN TRỌNG: Giữ chiều cao khung không bị mất */
    border-bottom: 1px solid #eee; /* Thêm đường kẻ dưới cho đẹp */
}
        .vvh-topics-nav::-webkit-scrollbar { height: 4px; }
        .vvh-topics-nav::-webkit-scrollbar-thumb { background: #ccc; border-radius: 4px; }
        
        .vvh-topic-btn {
    white-space: nowrap;
    flex-shrink: 0; /* QUAN TRỌNG: Không cho phép nút bị co lại khi thiếu chỗ */
    padding: 8px 16px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    border: 1px solid var(--vvh-border);
    background: #fff;
    color: var(--vvh-text-gray);
    cursor: pointer;
    transition: all 0.2s;
    height: 40px; /* Cố định chiều cao nút */
    display: flex;
    align-items: center;
    justify-content: center;
}
        .vvh-topic-btn.active, .vvh-topic-btn:hover {
            background: var(--vvh-text-dark);
            color: #fff;
            border-color: var(--vvh-text-dark);
        }

        /* List Videos */
        .vvh-video-list-container {
            flex: 1;
            overflow-y: auto;
            padding-right: 5px;
        }
        .vvh-video-list-container::-webkit-scrollbar { width: 5px; }
        .vvh-video-list-container::-webkit-scrollbar-thumb { background: #ccc; border-radius: 4px; }

        .vvh-video-item {
            display: flex;
            align-items: flex-start;
            gap: 10px;
            padding: 12px;
            border-bottom: 1px solid #eee;
            cursor: pointer;
            transition: 0.2s;
            border-radius: 6px;
        }
        .vvh-video-item:hover { background: rgba(0,0,0,0.03); }
        .vvh-video-item.active { 
            background: #e7f1ff; 
            border-left: 3px solid var(--vvh-primary);
        }
        .vvh-vid-icon { color: var(--vvh-text-gray); margin-top: 3px; font-size: 0.9rem; }
        .vvh-video-item.active .vvh-vid-icon { color: var(--vvh-primary); }
        
        .vvh-vid-info h4 {
            margin: 0; font-size: 0.95rem; font-weight: 500; color: var(--vvh-text-dark);
            display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
        }
        .vvh-video-item.active h4 { color: var(--vvh-primary); font-weight: 700; }
        .vvh-vid-meta { font-size: 0.8rem; color: var(--vvh-text-gray); margin-top: 4px; }


        /* Related Content Box */
        .vvh-related-box {
            background: #fdfdfd;
            border: 1px solid var(--vvh-border);
            border-radius: var(--vvh-radius);
            padding: 1.5rem;
            margin-bottom: 2rem;
        }
        .vvh-section-title {
            font-size: 1.2rem;
            font-weight: 700;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .vvh-related-links { list-style: none; padding: 0; margin: 0; }
        .vvh-related-links li { margin-bottom: 10px; }
        .vvh-related-links a {
            color: var(--vvh-text-dark);
            text-decoration: none;
            display: flex;
            align-items: baseline;
            gap: 8px;
            transition: 0.2s;
        }
        .vvh-related-links a:hover { color: var(--vvh-primary); }
        .vvh-related-links i { color: var(--vvh-primary); font-size: 0.8rem; }

        /* Author Box */
        .vvh-author-card {
            display: flex;
            align-items: center;
            gap: 20px;
            background: #fff;
            border: 1px solid var(--vvh-border);
            padding: 1.5rem;
            border-radius: var(--vvh-radius);
        }
        .vvh-author-img img {
            width: 100px; height: 100px; border-radius: 50%; object-fit: cover;
            border: 3px solid var(--vvh-bg-light);
        }
        .vvh-author-info h3 { margin: 0 0 5px; font-size: 1.1rem; font-weight: 700; }
        .vvh-author-info p { margin: 0; font-size: 0.95rem; color: var(--vvh-text-gray); }

        /* Responsive */
        @media (max-width: 991px) {
            .vvh-academy-container { grid-template-columns: 1fr; }
            .vvh-sidebar-section { height: auto; max-height: 500px; position: static; }
            .vvh-video-list-container { max-height: 400px; }
        }
        
        /* --- BỔ SUNG FIX LỖI LAYOUT CHO DISCLAIMER --- */
.vvh-content-container {
    max-width: 1400px; /* Giống với max-width của container khóa học */
    margin: 30px auto 0; /* Canh giữa và tạo khoảng cách với phần trên */
    padding: 0 20px; /* Thêm khoảng trống 2 bên cho an toàn */
    box-sizing: border-box;
}


/* --- HIỆU ỨNG ẨN/HIỆN NAVBAR --- */
#main-navbar {
    transition: transform 0.3s ease-in-out, opacity 0.3s ease-in-out;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1030; /* Đảm bảo nằm trên các thành phần khác */
}

/* Class này sẽ được thêm vào bằng JS khi cuộn xuống */
.nav-up {
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none; /* Ngăn click nhầm khi đang ẩn */
}

/* Brand Color cho X */
.btn-x { background-color: #000000; }

/* Style chung cho nút xã hội (nếu chưa có) */
.social-btn {
    display: inline-flex;
    align-items: center;
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 4px;
    font-weight: bold;
}

.social-btn svg {
    width: 20px;
    height: 20px;
    margin-right: 8px;
}

/* Màu riêng cho nút XING (tùy chọn) */
.btn-xing {
    border: 1px solid #e5e5e5; /* Hoặc màu nền bạn muốn */
    color: #333;
}

/* --- UI CARD MỚI --- */
.card-quiz {
    transition: transform 0.2s, box-shadow 0.2s;
}
.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1) !important;
}
.badge {
    font-weight: 500;
    letter-spacing: 0.3px;
    padding: 6px 10px;
    border-radius: 6px;
}
.bg-opacity-10 {
    --bs-bg-opacity: 0.1;
}
/* Fix lỗi link đè nhau khi dùng stretched-link */
.card-body {
    position: relative;
}
/* Đảm bảo nút "Làm bài ngay" nằm dưới cùng */
.card-body .mt-auto {
    margin-top: auto !important;
}

/* --- CSS CHO BADGE CHA/CON --- */
.quiz-badge.parent {
    background-color: #f8f9fa; /* Màu nền xám nhạt */
    color: #6c757d; /* Màu chữ xám */
    border: 1px solid #dee2e6; /* Viền nhẹ */
}
.quiz-badge.child {
    background: #f0f7ff; /* Màu nền xanh dương rất nhạt */
    color: #007bff; /* Màu chữ xanh dương */
    font-weight: 700;
}

/* Custom Footer Semantic SEO */
.vvh-main-footer {
    background-color: #1a1a1a;
    color: #f0f0f0; /* Chữ chính sáng hơn */
    padding: 60px 0 20px;
    font-size: 0.95rem;
    border-top: 4px solid #0d6efd;
}


.footer-brand-info img {
    filter: brightness(0) invert(1); /* Chuyển logo sang trắng nếu cần */
    margin-bottom: 20px;
}

.footer-title {
    color: #ffffff;
    font-weight: 700;
    font-size: 1.2rem;
    margin-bottom: 25px;
    position: relative;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.footer-title::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -8px;
    width: 40px;
    height: 2px;
    background-color: #0d6efd;
}

.footer-links {
    list-style: none;
    padding: 0;
}

/* Sửa các link text-muted ở cuối trang */
.vvh-main-footer .text-muted {
    color: #bbbbbb !important; /* Thay thế class mặc định của Bootstrap vốn quá tối */
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: #e0e0e0; /* Sáng hơn so với #adadad */
    text-decoration: none;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
}

.footer-links a i {
    margin-right: 10px;
    font-size: 0.8rem;
    color: #0d6efd;
}

.footer-links a:hover {
    color: #ffffff;
    padding-left: 5px;
}

.ecosystem-card {
    background: #252525;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 15px;
    border: 1px solid #333;
    transition: 0.3s;
}

.ecosystem-card:hover {
    border-color: #0d6efd;
    background: #2d2d2d;
}

.ecosystem-card h4 {
    font-size: 1rem;
    margin-bottom: 5px;
    color: #fff;
}

.ecosystem-card p {
    font-size: 0.8rem;
    margin-bottom: 0;
    color: #cccccc; /* Sáng hơn so với #888 */
}

.footer-bottom {
    margin-top: 50px;
    padding-top: 20px;
    border-top: 1px solid #333;
}

.social-circle-links a {
    width: 35px;
    height: 35px;
    line-height: 35px;
    display: inline-block;
    text-align: center;
    border-radius: 50%;
    background: #333;
    color: #fff;
    margin-right: 8px;
    transition: 0.3s;
}

.social-circle-links a:hover {
    background: #0d6efd;
    transform: translateY(-3px);
}

.social-circle-links a[title="LinkedIn"] { background-color: #08529c; color: #fff; }
.social-circle-links a[title="YouTube"] { background-color: #cc0000; color: #fff; }
.social-circle-links a[title="Twitter"] { background-color: #000000; color: #fff; }
/* Thêm vào file CSS của bạn */
.btn-ig {
    background: radial-gradient(circle at 30% 107%, #fdf497 0%, #fdf497 5%, #fd5949 45%, #d6249f 60%, #285AEB 90%);
    color: white; /* Màu chữ */
}

.btn-ig svg {
    fill: white; /* Màu icon */
}

/* Cấu trúc chung cho các nút */
.social-circle-links {
    display: flex;
    flex-wrap: wrap;
    gap: 10px; /* Khoảng cách giữa các icon */
}

.social-circle-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;  /* Kích thước chiều rộng */
    height: 40px; /* Kích thước chiều cao */
    border-radius: 50%; /* Bo tròn 100% */
    text-decoration: none;
    transition: transform 0.3s ease;
    background-color: #333; /* Màu nền mặc định nếu chưa định nghĩa */
}

/* Màu icon bên trong luôn là màu trắng */
.social-circle-links a i {
    color: #ffffff;
    font-size: 18px; /* Kích thước icon */
}

/* Hiệu ứng nhấc lên nhẹ khi di chuột */
.social-circle-links a:hover {
    transform: translateY(-3px);
    opacity: 0.9;
}

/* --- ĐỊNH NGHĨA MÀU SẮC TỪNG MẠNG XÃ HỘI --- */

/* Facebook (Xanh đậm) */
.social-circle-links a[title="Facebook"] {
    background-color: #3b5998;
}

/* LinkedIn (Xanh dương) */
.social-circle-links a[title="LinkedIn"] {
    background-color: #0077b5;
}

/* YouTube (Đỏ) */
.social-circle-links a[title="YouTube"] {
    background-color: #ff0000;
}

/* Twitter / X (Đen) */
.social-circle-links a[title="Twitter"] {
    background-color: #000000;
}

/* Pinterest (Đỏ đậm) */
.social-circle-links a[title="Pinterest"] {
    background-color: #bd081c;
}

/* Spotify (Xanh lá) */
.social-circle-links a[title="Spotify"] {
    background-color: #1db954;
}

/* Instagram (Gradient đặc trưng) */
.social-circle-links a[title="Instagram"] {
    background: radial-gradient(circle at 30% 107%, #fdf497 0%, #fdf497 5%, #fd5949 45%, #d6249f 60%, #285AEB 90%);
}

/* ==================================================
   YUMPU PUBLICATIONS SECTION - OPTIMIZED BY VVH
   ================================================== */

/* 1. Badge tổng số lượt xem phía trên */
.vvh-total-badge {
    background: var(--primary-color);
    color: #ffffff;
    padding: 10px 30px;
    border-radius: 50px;
    font-weight: 800;
    display: inline-flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 25px;
    box-shadow: 0 10px 20px rgba(0, 102, 204, 0.2);
    font-size: 1rem;
    border: 2px solid rgba(255, 255, 255, 0.1);
    transition: 0.3s;
}

.vvh-total-badge:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 25px rgba(0, 102, 204, 0.3);
}

.vvh-total-badge i {
    font-size: 1.2rem;
    animation: pulse-blue 2s infinite;
}

@keyframes pulse-blue {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

/* 2. Cấu trúc Card ấn phẩm */
.vvh-stats-card {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-radius: 20px;
    padding: 25px;
    text-align: center;
    transition: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
    height: 100%;
    display: flex;
    flex-direction: column;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.02);
}

.vvh-stats-card:hover {
    transform: translateY(-12px);
    border-color: var(--primary-color);
    box-shadow: 0 20px 40px rgba(0, 102, 204, 0.12);
}

/* 3. Ảnh minh chứng (Screenshot Yumpu) */
.vvh-stats-img {
    width: 100%;
    border-radius: 12px;
    overflow: hidden;
    margin-bottom: 20px;
    border: 1px solid #f0f0f0;
    aspect-ratio: 16 / 9;
}

.vvh-stats-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.vvh-stats-card:hover .vvh-stats-img img {
    transform: scale(1.1);
}

/* 4. Thông tin nền tảng & con số */
.vvh-stats-platform {
    display: inline-block;
    background: #f1f5f9;
    color: #475569;
    padding: 4px 15px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-bottom: 15px;
    text-transform: uppercase;
}

.vvh-stats-number {
    font-size: 3.2rem;
    font-weight: 900;
    color: var(--primary-color);
    line-height: 1;
    margin-bottom: 5px;
    letter-spacing: -1px;
}

.vvh-stats-label {
    font-size: 0.85rem;
    color: #64748b;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    margin-bottom: 20px;
}

/* 5. Tên ấn phẩm và phần Highlight */
.vvh-stats-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: #1e293b;
    line-height: 1.5;
    margin-top: auto; /* Đẩy xuống cuối card */
    padding: 0 10px;
}

.vvh-highlight-text {
    display: block;
    color: var(--primary-color);
    font-size: 1.25rem;
    font-weight: 800;
    margin: 8px 0;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* 6. Nút bấm đọc tài liệu */
.vvh-stats-card .vvh-btn.outline {
    background: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-color) !important;
    padding: 10px 25px;
    font-weight: 700;
    border-radius: 50px;
    margin-top: 20px;
    transition: 0.3s;
}

.vvh-stats-card .vvh-btn.outline:hover {
    background: var(--primary-color);
    color: #ffffff !important;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 102, 204, 0.3);
}

/* 7. Responsive Mobile */
@media (max-width: 768px) {
    .vvh-stats-number {
        font-size: 2.5rem;
    }
    .vvh-highlight-text {
        font-size: 1.1rem;
    }
    .vvh-total-badge {
        padding: 8px 20px;
        font-size: 0.85rem;
    }
}

/* --- COMMUNITY & SOCIAL FULL WIDTH STYLE --- */
.vvh-social-full-card {
    background: #fff;
    border-radius: 24px;
    padding: 40px;
    margin-bottom: 30px;
    border: 1px solid #f0f0f0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.03);
    transition: 0.3s;
    position: relative;
}

.vvh-social-full-card:hover {
    box-shadow: 0 20px 40px rgba(0, 102, 204, 0.08);
    transform: translateY(-5px);
}

.vvh-social-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    border-bottom: 1px solid #f8f9fa;
    padding-bottom: 20px;
}

.vvh-social-info h3 {
    font-size: 1.8rem;
    font-weight: 800;
    margin: 0;
}

.vvh-social-info p {
    margin: 5px 0 0;
    color: #64748b;
}

/* Container chứa các con số trải dài hàng ngang */
.vvh-social-stats-row {
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 35px;
}

.vvh-social-stat-item {
    text-align: center;
    min-width: 120px;
}

.vvh-social-stat-item i {
    font-size: 1.5rem;
    margin-bottom: 10px;
    display: block;
    opacity: 0.8;
}

.vvh-social-stat-item .count {
    font-size: 2rem;
    font-weight: 900;
    display: block;
    line-height: 1.2;
    color: #1e293b;
}

.vvh-social-stat-item .label {
    font-size: 0.75rem;
    font-weight: 700;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Custom màu sắc cho từng loại */
.card-genz i, .card-genz .count { color: var(--primary-color); }
.card-youtube i, .card-youtube .count { color: #cc0000; }

.vvh-social-badge {
    padding: 6px 16px;
    border-radius: 50px;
    font-size: 0.75rem;
    font-weight: 800;
    text-transform: uppercase;
}

@media (max-width: 768px) {
    .vvh-social-header { flex-direction: column; text-align: center; }
    .vvh-social-badge { margin-top: 15px; }
    .vvh-social-stat-item { min-width: 45%; }
    .vvh-social-info h3 { font-size: 1.4rem; }
}

/* --- TABLE OF CONTENTS (SIDE NAV) --- */
.vvh-toc-container {
    position: fixed;
    top: 50%;
    right: 30px; /* Đặt bên phải màn hình */
    transform: translateY(-50%);
    z-index: 1000;
    width: 220px;
    display: none; /* Mặc định ẩn trên mobile */
}

@media (min-width: 1200px) {
    .vvh-toc-container { display: block; }
}

.vvh-toc-wrapper {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    padding: 20px;
    border-radius: 16px;
    border: 1px solid #eee;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.vvh-toc-title {
    font-size: 0.75rem;
    font-weight: 800;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 15px;
    display: block;
}

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

.vvh-toc-item a {
    display: block;
    padding: 8px 0;
    color: #64748b;
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    transition: 0.3s;
    border-left: 2px solid transparent;
    padding-left: 15px;
    margin-left: -20px;
}

.vvh-toc-item a:hover, .vvh-toc-item.active a {
    color: var(--primary-color);
    border-left-color: var(--primary-color);
    background: linear-gradient(90deg, rgba(0,102,204,0.05) 0%, rgba(255,255,255,0) 100%);
}

/* Fix cuộn mượt cho toàn trang */
html {
    scroll-behavior: smooth;
}

/* --- MOBILE TOC STYLES --- */
.vvh-toc-mobile-btn {
    position: fixed;
    bottom: 30px;
    left: 20px; /* Đặt bên trái để tránh đè lên nút "Cuộn lên đầu" thường ở bên phải */
    z-index: 1040;
    background: var(--primary-color);
    color: #white;
    border: none;
    padding: 12px 20px;
    border-radius: 50px;
    box-shadow: 0 5px 20px rgba(0, 102, 204, 0.4);
    display: flex;
    align-items: center;
    gap: 10px;
    color: #fff !important;
    font-weight: 700;
    transition: 0.3s;
}

.vvh-toc-mobile-btn:active {
    transform: scale(0.9);
}

.vvh-toc-offcanvas {
    width: 280px !important;
    border-radius: 0 20px 20px 0;
}

.vvh-mobile-toc-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.vvh-mobile-toc-list li a {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 15px 20px;
    color: #334155;
    text-decoration: none;
    font-weight: 600;
    border-bottom: 1px solid #f1f5f9;
    transition: 0.2s;
}

.vvh-mobile-toc-list li a i {
    width: 20px;
    color: var(--primary-color);
    text-align: center;
}

.vvh-mobile-toc-list li a:active {
    background-color: #f8fafc;
    color: var(--primary-color);
}

/* Hiệu ứng ẩn nút khi cuộn xuống ở trang làm bài (nếu cần) */
body.page-quiz .vvh-toc-mobile-btn {
    display: none !important;
}