/* ===== TOKENS ===== */
        :root {
            --stone-50: #F1ECE2;
            --stone-100: #E7DECC;
            --stone-200: #D9CBAD;
            --basalt-900: #16171A;
            --basalt-800: #212226;
            --basalt-700: #2C2D32;
            --brass-500: #AD8348;
            --brass-400: #C9A469;
            --verde-600: #54614C;
            --verde-500: #6C7A62;
            --fleck-50: #FAF7EF;
            --ink-800: #2A271F;
            --ink-600: #524C3F;
            --ink-400: #8A8371;
            --line: rgba(42, 39, 31, 0.14);
            --line-dark: rgba(250, 247, 239, 0.14);
            --radius: 2px;
            --serif: 'Playfair Display', serif;
            --sans: 'Be Vietnam Pro', sans-serif;
        }

        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: var(--sans);
            background: var(--stone-50);
            color: var(--ink-800);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            overflow-x: hidden;
        }
        img {
            max-width: 100%;
            display: block;
        }
        a {
            text-decoration: none;
            color: inherit;
        }
        button {
            font-family: inherit;
            cursor: pointer;
            border: none;
            background: none;
        }
        :focus-visible {
            outline: 2px solid var(--brass-500);
            outline-offset: 3px;
        }
        @media (prefers-reduced-motion: reduce) {
            * {
                animation: none !important;
                transition: none !important;
            }
        }

        .eyebrow {
            font-family: var(--sans);
            font-weight: 700;
            font-size: 0.72rem;
            letter-spacing: 0.22em;
            text-transform: uppercase;
            color: var(--brass-500);
            display: flex;
            align-items: center;
            gap: 0.6em;
        }
        .eyebrow::before {
            content: '';
            width: 22px;
            height: 1px;
            background: var(--brass-500);
        }

        /* ===== HEADER ===== */
        header {
            position: sticky;
            top: 0;
            z-index: 200;
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 1.1rem 2.5rem;
            background: rgba(241, 236, 226, 0.92);
            backdrop-filter: blur(10px);
            border-bottom: 1px solid var(--line);
        }
        .logo {
            font-family: var(--serif);
            font-weight: 700;
            font-size: 1.5rem;
            letter-spacing: 0.02em;
            color: var(--ink-800);
        }
        .logo span {
            color: var(--brass-500);
        }
        .nav-links {
            display: flex;
            list-style: none;
            gap: 2.2rem;
        }
        .nav-links a {
            font-size: 0.82rem;
            font-weight: 600;
            letter-spacing: 0.08em;
            text-transform: uppercase;
            color: var(--ink-600);
            position: relative;
            padding-bottom: 4px;
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            left: 0;
            bottom: 0;
            width: 0;
            height: 1px;
            background: var(--brass-500);
            transition: width 0.25s ease;
        }
        .nav-links a:hover::after,
        .nav-links a.active::after {
            width: 100%;
        }
        .nav-links a:hover,
        .nav-links a.active {
            color: var(--ink-800);
        }
        .header-actions {
            display: flex;
            gap: 0.8rem;
        }
        .action-btn {
            display: inline-flex;
            align-items: center;
            gap: 0.5em;
            font-size: 0.78rem;
            font-weight: 700;
            letter-spacing: 0.06em;
            padding: 0.65em 1.1em;
            border-radius: var(--radius);
            border: 1px solid var(--ink-800);
            color: var(--ink-800);
            transition: all 0.2s ease;
            white-space: nowrap;
        }
        .action-btn:hover {
            background: var(--ink-800);
            color: var(--stone-50);
        }
        .zalo-btn {
            background: var(--brass-500);
            border-color: var(--brass-500);
            color: var(--fleck-50);
        }
        .zalo-btn:hover {
            background: var(--brass-400);
            border-color: var(--brass-400);
            color: var(--basalt-900);
        }
        .mobile-only {
            display: none;
        }
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            cursor: pointer;
        }
        .hamburger span {
            width: 24px;
            height: 2px;
            background: var(--ink-800);
            transition: 0.25s;
        }

        /* ===== BREADCRUMB ===== */
        .breadcrumb {
            padding: 1rem 2.5rem 0;
            max-width: 1400px;
            margin: 0 auto;
            font-size: 0.78rem;
            color: var(--ink-400);
        }
        .breadcrumb a {
            color: var(--ink-600);
            transition: color 0.2s ease;
        }
        .breadcrumb a:hover {
            color: var(--brass-500);
        }
        .breadcrumb .sep {
            margin: 0 0.5rem;
            color: var(--ink-400);
        }
        .breadcrumb .current {
            color: var(--ink-600);
            font-weight: 500;
        }

        /* ===== BLOG HERO ===== */
        .blog-hero {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 3rem;
            padding: 3rem 2.5rem 4rem;
            max-width: 1400px;
            margin: 0 auto;
            align-items: center;
        }
        .blog-hero-content .eyebrow {
            margin-bottom: 0.8rem;
        }
        .blog-hero-content h1 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: clamp(2.2rem, 3.8vw, 3.6rem);
            line-height: 1.1;
            color: var(--ink-800);
            margin-bottom: 1rem;
            letter-spacing: -0.02em;
        }
        .blog-hero-desc {
            font-size: 1.1rem;
            color: var(--ink-600);
            max-width: 36em;
            margin-bottom: 1.2rem;
            line-height: 1.7;
        }
        .blog-hero-meta {
            display: flex;
            flex-wrap: wrap;
            gap: 1.2rem;
            font-size: 0.82rem;
            color: var(--ink-400);
            margin-bottom: 1.5rem;
        }
        .blog-hero-meta i {
            margin-right: 0.3rem;
            color: var(--brass-500);
        }
        .blog-hero-cta {
            display: flex;
            flex-wrap: wrap;
            gap: 0.8rem;
        }
        .btn-primary {
            background: var(--basalt-900);
            color: var(--fleck-50);
            padding: 0.9em 2em;
            font-weight: 700;
            font-size: 0.82rem;
            letter-spacing: 0.08em;
            text-transform: uppercase;
            border-radius: var(--radius);
            transition: transform 0.2s ease, background 0.2s ease;
            display: inline-block;
            border: none;
        }
        .btn-primary:hover {
            background: var(--brass-500);
            transform: translateY(-2px);
        }
        .btn-outline {
            border: 1px solid var(--ink-800);
            color: var(--ink-800);
            padding: 0.9em 2em;
            font-weight: 700;
            font-size: 0.82rem;
            letter-spacing: 0.08em;
            text-transform: uppercase;
            border-radius: var(--radius);
            transition: all 0.2s ease;
            display: inline-block;
        }
        .btn-outline:hover {
            background: var(--ink-800);
            color: var(--stone-50);
        }
        .btn-download {
            background: var(--brass-500);
            color: var(--basalt-900);
            padding: 1em 3em;
            font-weight: 700;
            font-size: 0.9rem;
            letter-spacing: 0.08em;
            text-transform: uppercase;
            border-radius: var(--radius);
            transition: transform 0.2s ease, background 0.2s ease;
            display: inline-block;
            border: none;
        }
        .btn-download:hover {
            background: var(--brass-400);
            transform: translateY(-2px);
        }

        .blog-hero-image {
            position: relative;
            border-radius: var(--radius);
            overflow: hidden;
            aspect-ratio: 4/3;
            background: var(--basalt-800);
        }
        .blog-hero-image img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }
        .hero-image-badge {
            position: absolute;
            bottom: 1.2rem;
            left: 1.2rem;
            right: 1.2rem;
            display: flex;
            flex-wrap: wrap;
            gap: 0.8rem;
            background: rgba(22, 23, 26, 0.7);
            backdrop-filter: blur(4px);
            padding: 0.8rem 1.2rem;
            border-radius: var(--radius);
            color: var(--fleck-50);
            font-size: 0.75rem;
            border: 1px solid rgba(250, 247, 239, 0.1);
        }
        .hero-image-badge i {
            color: var(--brass-400);
            margin-right: 0.3rem;
        }
        .hero-image-badge span {
            display: flex;
            align-items: center;
            gap: 0.3rem;
        }

        /* ===== TABLE OF CONTENTS ===== */
        .toc-box {
            background: var(--stone-100);
            padding: 1.5rem 2rem;
            border-radius: var(--radius);
            margin: 1.5rem 0 2.5rem;
        }
        .toc-box h3 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: 1.1rem;
            margin-bottom: 0.5rem;
        }
        .toc-box ul {
            list-style: none;
            margin: 0;
            padding: 0;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 0.3rem 1.5rem;
        }
        .toc-box ul li::before {
            content: "• ";
            color: var(--brass-500);
            font-weight: 700;
        }
        .toc-box ul li a {
            color: var(--brass-500);
            font-weight: 500;
            font-size: 0.9rem;
        }
        .toc-box ul li a:hover {
            color: var(--ink-800);
        }

        /* ===== BLOG CONTENT ===== */
        .blog-content-wrapper {
            max-width: 1000px;
            margin: 0 auto;
            padding: 0 2.5rem 4rem;
        }
        .blog-content-wrapper h2 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: clamp(1.6rem, 2.4vw, 2.2rem);
            color: var(--ink-800);
            margin-top: 2.5rem;
            margin-bottom: 1rem;
            line-height: 1.2;
        }
        .blog-content-wrapper p {
            font-size: 1rem;
            color: var(--ink-600);
            line-height: 1.8;
            margin-bottom: 1rem;
        }
        .blog-content-wrapper ul {
            margin: 0.5rem 0 1.5rem 1.5rem;
        }
        .blog-content-wrapper ul li {
            font-size: 0.95rem;
            color: var(--ink-600);
            line-height: 1.8;
            margin-bottom: 0.3rem;
        }
        .blog-content-wrapper .highlight-box {
            background: var(--stone-100);
            border-left: 3px solid var(--brass-500);
            padding: 1.5rem 2rem;
            margin: 1.5rem 0;
            border-radius: var(--radius);
        }
        .blog-content-wrapper .highlight-box p {
            margin-bottom: 0;
            font-size: 0.95rem;
        }

        /* ===== CATALOGUE PREVIEW ===== */
        .catalogue-preview {
            display: grid;
            grid-template-columns: 1fr 1fr 1fr;
            gap: 1.5rem;
            margin: 2rem 0;
        }
        .preview-item {
            background: var(--fleck-50);
            border-radius: var(--radius);
            overflow: hidden;
            border: 1px solid var(--line);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }
        .preview-item:hover {
            transform: translateY(-4px);
            box-shadow: 0 20px 40px -20px rgba(22, 23, 26, 0.2);
        }
        .preview-item img {
            width: 100%;
            aspect-ratio: 4/3;
            object-fit: cover;
            transition: transform 0.5s ease;
        }
        .preview-item:hover img {
            transform: scale(1.04);
        }
        .preview-item .info {
            padding: 1rem 1.2rem 1.2rem;
        }
        .preview-item .info .cat {
            font-size: 0.6rem;
            font-weight: 700;
            letter-spacing: 0.06em;
            text-transform: uppercase;
            color: var(--brass-500);
        }
        .preview-item .info h4 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: 0.95rem;
            margin-top: 0.2rem;
        }

        /* ===== DOWNLOAD CTA ===== */
        .download-cta {
            text-align: center;
            padding: 3rem;
            background: var(--basalt-900);
            color: var(--fleck-50);
            border-radius: var(--radius);
            margin: 2rem 0;
        }
        .download-cta h3 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: 1.8rem;
            margin-bottom: 0.5rem;
        }
        .download-cta p {
            color: rgba(250, 247, 239, 0.6);
            margin-bottom: 1.5rem;
        }

        /* ===== FINAL CTA ===== */
        .final-cta-box {
            background: var(--basalt-900);
            color: var(--fleck-50);
            padding: 2.5rem;
            text-align: center;
            border-radius: var(--radius);
            margin: 2rem 0;
        }
        .final-cta-box h3 {
            font-family: var(--serif);
            font-size: 1.5rem;
            margin-bottom: 0.5rem;
        }
        .final-cta-box p {
            color: rgba(250, 247, 239, 0.6);
            margin-bottom: 1.2rem;
        }
        .final-cta-box .btn-primary {
            background: var(--brass-500);
            color: var(--basalt-900);
            display: inline-block;
        }
        .final-cta-box .btn-primary:hover {
            background: var(--brass-400);
        }

        /* ===== RELATED POSTS ===== */
        .related-posts {
            padding: 3rem 2.5rem 4rem;
            max-width: 1400px;
            margin: 0 auto;
        }
        .related-posts h3 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: 1.5rem;
            margin-bottom: 1.5rem;
            text-align: center;
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.2rem;
        }
        .related-item {
            background: var(--fleck-50);
            border-radius: var(--radius);
            overflow: hidden;
            border: 1px solid var(--line);
            transition: transform 0.25s ease;
        }
        .related-item:hover {
            transform: translateY(-3px);
        }
        .related-item img {
            width: 100%;
            aspect-ratio: 16/9;
            object-fit: cover;
        }
        .related-item .info {
            padding: 0.8rem 1rem 1rem;
        }
        .related-item .info .badge {
            font-size: 0.6rem;
            font-weight: 700;
            letter-spacing: 0.06em;
            text-transform: uppercase;
            color: var(--brass-500);
        }
        .related-item .info h4 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: 0.9rem;
            margin-top: 0.2rem;
            line-height: 1.3;
        }
        .related-item .info .read-more {
            font-size: 0.75rem;
            color: var(--brass-500);
            font-weight: 600;
            display: inline-block;
            margin-top: 0.4rem;
        }

        /* ===== LEAD SECTION ===== */
        .lead-section {
            background: var(--basalt-900);
            color: var(--fleck-50);
            padding: 4rem 2.5rem;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .lead-section::before {
            content: '';
            position: absolute;
            inset: 0;
            opacity: 0.2;
            background-image:
                radial-gradient(circle at 20% 30%, var(--brass-400) 4px, transparent 4px),
                radial-gradient(circle at 70% 60%, var(--fleck-50) 6px, transparent 6px);
            background-size: 120px 120px;
        }
        .lead-section h2 {
            font-family: var(--serif);
            font-weight: 600;
            font-size: clamp(1.7rem, 2.6vw, 2.3rem);
            position: relative;
            z-index: 1;
            margin-bottom: 0.5rem;
        }
        .lead-section .sub {
            color: rgba(250, 247, 239, 0.6);
            margin-bottom: 2rem;
            position: relative;
            z-index: 1;
            font-size: 1rem;
        }
        .lead-form {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 0.9rem;
            position: relative;
            z-index: 1;
            max-width: 800px;
            margin: 0 auto;
        }
        .lead-form input,
        .lead-form select {
            padding: 0.9em 1.2em;
            border-radius: var(--radius);
            border: 1px solid rgba(250, 247, 239, 0.25);
            background: rgba(250, 247, 239, 0.06);
            color: var(--fleck-50);
            font-family: var(--sans);
            font-size: 0.9rem;
            flex: 1;
            min-width: 200px;
        }
        .lead-form input::placeholder {
            color: rgba(250, 247, 239, 0.45);
        }
        .lead-form select {
            color: rgba(250, 247, 239, 0.75);
        }
        .lead-form select option {
            color: var(--ink-800);
        }
        .lead-form button {
            background: var(--brass-500);
            color: var(--basalt-900);
            font-weight: 700;
            font-size: 0.82rem;
            letter-spacing: 0.06em;
            text-transform: uppercase;
            padding: 0.9em 2.5em;
            border-radius: var(--radius);
            transition: background 0.2s ease, transform 0.2s ease;
        }
        .lead-form button:hover {
            background: var(--brass-400);
            transform: translateY(-2px);
        }
        .lead-note {
            font-size: 0.75rem;
            color: rgba(250, 247, 239, 0.4);
            margin-top: 1rem;
            position: relative;
            z-index: 1;
        }

        /* ===== FOOTER ===== */
        footer {
            background: var(--basalt-900);
            color: rgba(250, 247, 239, 0.7);
            padding: 3.5rem 2.5rem 1.5rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.4fr 1fr 1fr;
            gap: 2.5rem;
            max-width: 1400px;
            margin: 0 auto 2rem;
            padding-bottom: 2rem;
            border-bottom: 1px solid var(--line-dark);
        }
        footer h4 {
            font-family: var(--serif);
            color: var(--fleck-50);
            font-weight: 600;
            margin-bottom: 1rem;
            font-size: 1.02rem;
        }
        footer p {
            font-size: 0.85rem;
            margin-bottom: 0.5rem;
            line-height: 1.7;
        }
        .footer-bottom {
            text-align: center;
            font-size: 0.75rem;
            color: rgba(250, 247, 239, 0.4);
            max-width: 1400px;
            margin: 0 auto;
        }

        /* ===== FLOAT & STICKY ===== */
        .float-icons {
            position: fixed;
            right: 1.4rem;
            bottom: 2rem;
            z-index: 300;
            display: flex;
            flex-direction: column;
            gap: 0.8rem;
        }
        .float-btn {
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            background: var(--basalt-900);
            color: var(--fleck-50);
            box-shadow: 0 10px 25px -8px rgba(22, 23, 26, 0.4);
            font-size: 1.1rem;
            transition: transform 0.2s ease;
        }
        .float-btn:hover {
            transform: scale(1.08);
        }
        .float-btn.zalo {
            background: var(--brass-500);
            color: var(--basalt-900);
        }
        .sticky-cta {
            display: none;
            position: fixed;
            bottom: 0;
            left: 0;
            right: 0;
            z-index: 300;
            background: var(--basalt-900);
            border-top: 1px solid var(--line-dark);
            padding: 0.5rem 1rem;
        }
        .sticky-cta-inner {
            display: flex;
            gap: 0.8rem;
            max-width: 600px;
            margin: 0 auto;
        }
        .sticky-btn {
            flex: 1;
            text-align: center;
            padding: 0.8rem 0.5rem;
            font-weight: 700;
            font-size: 0.75rem;
            letter-spacing: 0.04em;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5em;
            border-radius: var(--radius);
            text-transform: uppercase;
        }
        .sticky-btn.call {
            background: transparent;
            color: var(--fleck-50);
            border: 1px solid rgba(250, 247, 239, 0.2);
        }
        .sticky-btn.lead {
            background: var(--brass-500);
            color: var(--basalt-900);
        }

        /* ===== RESPONSIVE ===== */
        @media (max-width: 980px) {
            .blog-hero {
                grid-template-columns: 1fr;
                padding: 2rem 1.3rem 2.5rem;
            }
            .blog-hero-image {
                order: -1;
                max-height: 320px;
            }
            .blog-content-wrapper {
                padding: 0 1.3rem 3rem;
            }
            .catalogue-preview {
                grid-template-columns: 1fr 1fr;
            }
            .related-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .toc-box ul {
                grid-template-columns: 1fr;
            }
            header {
                padding: 1rem 1.3rem;
            }
            .header-actions {
                display: none;
            }
            .mobile-only {
                display: block;
            }
            .hamburger {
                display: flex;
            }
            .nav-links {
                position: fixed;
                top: 64px;
                left: 0;
                right: 0;
                background: var(--stone-50);
                flex-direction: column;
                padding: 1.5rem;
                gap: 1.1rem;
                border-bottom: 1px solid var(--line);
                transform: translateY(-120%);
                transition: transform 0.3s ease;
                opacity: 0;
            }
            .nav-links.active {
                transform: translateY(0);
                opacity: 1;
            }
            .blog-hero-cta {
                flex-direction: column;
                align-items: flex-start;
            }
            .blog-hero-cta .btn-primary,
            .blog-hero-cta .btn-outline,
            .blog-hero-cta .btn-download {
                width: 100%;
                text-align: center;
            }
            .footer-grid {
                grid-template-columns: 1fr;
            }
        }

        @media (max-width: 680px) {
            .catalogue-preview {
                grid-template-columns: 1fr;
            }
            .related-grid {
                grid-template-columns: 1fr;
            }
            .toc-box {
                padding: 1rem 1.2rem;
            }
            .toc-box ul {
                grid-template-columns: 1fr;
            }
            .blog-hero-cta {
                flex-direction: column;
                align-items: flex-start;
            }
            .blog-hero-cta .btn-primary,
            .blog-hero-cta .btn-outline,
            .blog-hero-cta .btn-download {
                width: 100%;
                text-align: center;
            }
            .lead-form input,
            .lead-form select {
                min-width: 100%;
            }
            .sticky-cta {
                display: block;
            }
            .float-icons {
                bottom: 5.2rem;
                right: 1rem;
            }
            .download-cta {
                padding: 2rem 1.3rem;
            }
            .download-cta h3 {
                font-size: 1.4rem;
            }
            .final-cta-box {
                padding: 1.8rem 1.2rem;
            }
            .breadcrumb {
                padding: 0.8rem 1.3rem 0;
                font-size: 0.7rem;
            }
        }