/* roulang page: index */
:root {
            --color-primary: #0b2d5b;
            --color-primary-light: #153d73;
            --color-accent: #d4a853;
            --color-accent-hover: #c4963e;
            --color-highlight: #1e6eb8;
            --color-dark: #071a2e;
            --color-text: #1a1a2e;
            --color-text-light: #4a5568;
            --color-text-muted: #718096;
            --color-bg: #f7f8fa;
            --color-bg-alt: #eef1f6;
            --color-white: #ffffff;
            --color-border: #e2e6ed;
            --color-border-light: #edf0f5;
            --radius-sm: 8px;
            --radius-md: 14px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08), 0 2px 6px rgba(0, 0, 0, 0.04);
            --shadow-lg: 0 12px 36px rgba(0, 0, 0, 0.10), 0 4px 12px rgba(0, 0, 0, 0.05);
            --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.12), 0 8px 20px rgba(0, 0, 0, 0.06);
            --transition-fast: 0.18s ease;
            --transition-normal: 0.28s ease;
            --transition-slow: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            --font-sans: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
            --max-width: 1200px;
            --nav-height: 72px;
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
        }

        html {
            scroll-behavior: smooth;
            scroll-padding-top: var(--nav-height);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
            background-color: var(--color-bg);
            margin: 0;
            padding: 0;
            overflow-x: hidden;
        }

        a {
            text-decoration: none;
            color: inherit;
            transition: color var(--transition-fast);
        }
        a:hover {
            color: var(--color-highlight);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        button,
        input,
        textarea,
        select {
            font-family: inherit;
            font-size: inherit;
            outline: none;
        }
        button {
            cursor: pointer;
            border: none;
            background: none;
        }
        ul,
        ol {
            list-style: none;
            margin: 0;
            padding: 0;
        }
        h1,
        h2,
        h3,
        h4,
        h5,
        h6 {
            margin: 0;
            line-height: 1.3;
            font-weight: 700;
            color: var(--color-text);
        }
        p {
            margin: 0;
            color: var(--color-text-light);
        }
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }
        @media (max-width: 768px) {
            .container {
                padding: 0 18px;
            }
        }

        .section-padding {
            padding: 90px 0;
        }
        @media (max-width: 1024px) {
            .section-padding {
                padding: 64px 0;
            }
        }
        @media (max-width: 520px) {
            .section-padding {
                padding: 48px 0;
            }
        }

        .section-header {
            text-align: center;
            margin-bottom: 56px;
        }
        .section-header h2 {
            font-size: 2.2rem;
            font-weight: 700;
            color: var(--color-dark);
            margin-bottom: 12px;
            letter-spacing: -0.3px;
        }
        .section-header .section-subtitle {
            font-size: 1.05rem;
            color: var(--color-text-muted);
            max-width: 560px;
            margin: 0 auto;
        }
        @media (max-width: 768px) {
            .section-header h2 {
                font-size: 1.7rem;
            }
            .section-header .section-subtitle {
                font-size: 0.95rem;
            }
        }

        .text-accent {
            color: var(--color-accent);
        }
        .text-highlight {
            color: var(--color-highlight);
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 13px 28px;
            border-radius: 50px;
            font-weight: 600;
            font-size: 0.95rem;
            letter-spacing: 0.2px;
            transition: all var(--transition-normal);
            white-space: nowrap;
            cursor: pointer;
            text-align: center;
            line-height: 1.3;
        }
        .btn-primary {
            background: var(--color-accent);
            color: var(--color-white);
            box-shadow: 0 4px 14px rgba(212, 168, 83, 0.35);
            border: 2px solid var(--color-accent);
        }
        .btn-primary:hover {
            background: var(--color-accent-hover);
            border-color: var(--color-accent-hover);
            box-shadow: 0 6px 22px rgba(212, 168, 83, 0.45);
            transform: translateY(-2px);
            color: var(--color-white);
        }
        .btn-outline {
            background: transparent;
            color: var(--color-white);
            border: 2px solid rgba(255, 255, 255, 0.6);
        }
        .btn-outline:hover {
            background: rgba(255, 255, 255, 0.12);
            border-color: rgba(255, 255, 255, 0.9);
            color: var(--color-white);
            transform: translateY(-2px);
        }
        .btn-outline-dark {
            background: transparent;
            color: var(--color-primary);
            border: 2px solid var(--color-primary);
        }
        .btn-outline-dark:hover {
            background: var(--color-primary);
            color: var(--color-white);
            transform: translateY(-2px);
        }
        .btn-sm {
            padding: 9px 20px;
            font-size: 0.85rem;
            border-radius: 40px;
        }
        .btn-lg {
            padding: 16px 36px;
            font-size: 1.05rem;
            border-radius: 56px;
        }

        .tag {
            display: inline-block;
            padding: 5px 14px;
            border-radius: 30px;
            font-size: 0.8rem;
            font-weight: 600;
            letter-spacing: 0.4px;
            text-transform: uppercase;
        }
        .tag-accent {
            background: rgba(212, 168, 83, 0.12);
            color: var(--color-accent);
        }
        .tag-blue {
            background: rgba(30, 110, 184, 0.1);
            color: var(--color-highlight);
        }

        .card {
            background: var(--color-white);
            border-radius: var(--radius-lg);
            padding: 32px 28px;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--color-border-light);
            transition: all var(--transition-normal);
            height: 100%;
            display: flex;
            flex-direction: column;
        }
        .card:hover {
            box-shadow: var(--shadow-lg);
            transform: translateY(-4px);
            border-color: transparent;
        }
        .card .card-icon {
            width: 56px;
            height: 56px;
            border-radius: var(--radius-md);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            margin-bottom: 18px;
            flex-shrink: 0;
        }
        .card .card-icon.icon-blue {
            background: rgba(30, 110, 184, 0.1);
            color: var(--color-highlight);
        }
        .card .card-icon.icon-gold {
            background: rgba(212, 168, 83, 0.12);
            color: var(--color-accent);
        }
        .card .card-icon.icon-dark {
            background: rgba(7, 26, 46, 0.06);
            color: var(--color-dark);
        }
        .card h3 {
            font-size: 1.15rem;
            margin-bottom: 10px;
            color: var(--color-dark);
        }
        .card p {
            font-size: 0.93rem;
            color: var(--color-text-muted);
            line-height: 1.65;
            flex-grow: 1;
        }

        .stat-card {
            text-align: center;
            padding: 28px 20px;
            border-radius: var(--radius-lg);
            background: var(--color-white);
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--color-border-light);
            transition: all var(--transition-normal);
        }
        .stat-card:hover {
            box-shadow: var(--shadow-md);
            transform: translateY(-3px);
        }
        .stat-card .stat-number {
            font-size: 2.8rem;
            font-weight: 800;
            color: var(--color-primary);
            letter-spacing: -1px;
            line-height: 1;
            margin-bottom: 6px;
        }
        .stat-card .stat-label {
            font-size: 0.9rem;
            color: var(--color-text-muted);
            font-weight: 500;
        }

        .case-card {
            border-radius: var(--radius-lg);
            overflow: hidden;
            background: var(--color-white);
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--color-border-light);
            transition: all var(--transition-normal);
            height: 100%;
            display: flex;
            flex-direction: column;
        }
        .case-card:hover {
            box-shadow: var(--shadow-lg);
            transform: translateY(-5px);
        }
        .case-card .case-img-wrap {
            position: relative;
            overflow: hidden;
            aspect-ratio: 16 / 10;
            flex-shrink: 0;
        }
        .case-card .case-img-wrap img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform var(--transition-slow);
        }
        .case-card:hover .case-img-wrap img {
            transform: scale(1.06);
        }
        .case-card .case-img-wrap .case-overlay {
            position: absolute;
            inset: 0;
            background: linear-gradient(to top, rgba(7, 26, 46, 0.55) 0%, rgba(7, 26, 46, 0.05) 60%);
            pointer-events: none;
        }
        .case-card .case-body {
            padding: 20px 22px;
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }
        .case-card .case-body h3 {
            font-size: 1.05rem;
            margin-bottom: 6px;
            color: var(--color-dark);
        }
        .case-card .case-body p {
            font-size: 0.88rem;
            color: var(--color-text-muted);
            flex-grow: 1;
        }
        .case-card .case-body .case-tag-row {
            margin-top: 12px;
            display: flex;
            flex-wrap: wrap;
            gap: 6px;
        }

        .process-step {
            display: flex;
            gap: 20px;
            align-items: flex-start;
            padding: 22px 0;
            border-bottom: 1px solid var(--color-border-light);
            transition: all var(--transition-fast);
        }
        .process-step:last-child {
            border-bottom: none;
        }
        .process-step .step-num {
            flex-shrink: 0;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--color-primary);
            color: var(--color-white);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 1.2rem;
            transition: all var(--transition-normal);
        }
        .process-step:hover .step-num {
            background: var(--color-accent);
            transform: scale(1.08);
        }
        .process-step .step-content h4 {
            font-size: 1.05rem;
            color: var(--color-dark);
            margin-bottom: 4px;
        }
        .process-step .step-content p {
            font-size: 0.9rem;
            color: var(--color-text-muted);
        }

        .faq-item {
            border-bottom: 1px solid var(--color-border-light);
            padding: 18px 0;
            cursor: pointer;
            transition: all var(--transition-fast);
        }
        .faq-item .faq-question {
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 600;
            font-size: 1.02rem;
            color: var(--color-dark);
            gap: 16px;
        }
        .faq-item .faq-question i {
            transition: transform var(--transition-normal);
            color: var(--color-text-muted);
            flex-shrink: 0;
        }
        .faq-item.open .faq-question i {
            transform: rotate(180deg);
            color: var(--color-accent);
        }
        .faq-item .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-slow), padding var(--transition-normal);
            color: var(--color-text-light);
            font-size: 0.93rem;
            line-height: 1.7;
        }
        .faq-item.open .faq-answer {
            max-height: 300px;
            padding-top: 12px;
        }
        .faq-item:hover .faq-question {
            color: var(--color-highlight);
        }

        .contact-form-wrap {
            background: var(--color-white);
            border-radius: var(--radius-xl);
            padding: 40px 36px;
            box-shadow: var(--shadow-lg);
            border: 1px solid var(--color-border-light);
        }
        .contact-form-wrap input,
        .contact-form-wrap textarea {
            width: 100%;
            padding: 13px 16px;
            border-radius: var(--radius-sm);
            border: 2px solid var(--color-border);
            font-size: 0.95rem;
            transition: all var(--transition-fast);
            background: var(--color-bg);
            color: var(--color-text);
        }
        .contact-form-wrap input:focus,
        .contact-form-wrap textarea:focus {
            border-color: var(--color-highlight);
            box-shadow: 0 0 0 4px rgba(30, 110, 184, 0.08);
            background: var(--color-white);
        }
        .contact-form-wrap textarea {
            min-height: 130px;
            resize: vertical;
        }
        .contact-form-wrap label {
            font-weight: 600;
            font-size: 0.9rem;
            color: var(--color-text);
            margin-bottom: 6px;
            display: block;
        }
        .contact-form-wrap .form-group {
            margin-bottom: 18px;
        }

        footer {
            background: var(--color-dark);
            color: rgba(255, 255, 255, 0.7);
            padding: 56px 0 32px;
            font-size: 0.9rem;
        }
        footer .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 36px;
        }
        @media (max-width: 768px) {
            footer .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 28px;
            }
        }
        @media (max-width: 520px) {
            footer .footer-grid {
                grid-template-columns: 1fr;
                gap: 22px;
            }
        }
        footer .footer-col h4 {
            color: var(--color-white);
            font-size: 1rem;
            margin-bottom: 14px;
            font-weight: 600;
        }
        footer .footer-col a {
            color: rgba(255, 255, 255, 0.6);
            display: block;
            padding: 4px 0;
            transition: color var(--transition-fast);
            font-size: 0.88rem;
        }
        footer .footer-col a:hover {
            color: var(--color-accent);
        }
        footer .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.12);
            padding-top: 20px;
            text-align: center;
            font-size: 0.82rem;
            color: rgba(255, 255, 255, 0.45);
        }

        .header-nav {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            height: var(--nav-height);
            display: flex;
            align-items: center;
            background: rgba(255, 255, 255, 0.08);
            backdrop-filter: blur(22px);
            -webkit-backdrop-filter: blur(22px);
            border-bottom: 1px solid rgba(255, 255, 255, 0.18);
            transition: all var(--transition-normal);
        }
        .header-nav.scrolled {
            background: rgba(255, 255, 255, 0.94);
            backdrop-filter: blur(18px);
            -webkit-backdrop-filter: blur(18px);
            border-bottom: 1px solid rgba(0, 0, 0, 0.06);
            box-shadow: 0 2px 18px rgba(0, 0, 0, 0.07);
        }
        .header-nav .nav-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
        }
        .header-nav .logo {
            font-weight: 800;
            font-size: 1.35rem;
            letter-spacing: 0.5px;
            color: #ffffff;
            display: flex;
            align-items: center;
            gap: 8px;
            transition: color var(--transition-normal);
            flex-shrink: 0;
        }
        .header-nav.scrolled .logo {
            color: var(--color-primary);
        }
        .header-nav .logo .logo-icon {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--color-accent);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1rem;
            color: #fff;
            flex-shrink: 0;
        }
        .header-nav .nav-links {
            display: flex;
            align-items: center;
            gap: 28px;
        }
        .header-nav .nav-links a {
            font-weight: 500;
            font-size: 0.93rem;
            color: rgba(255, 255, 255, 0.9);
            transition: all var(--transition-fast);
            position: relative;
            padding: 4px 0;
            white-space: nowrap;
        }
        .header-nav.scrolled .nav-links a {
            color: var(--color-text);
        }
        .header-nav .nav-links a:hover,
        .header-nav .nav-links a.active {
            color: var(--color-accent);
        }
        .header-nav .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--color-accent);
            border-radius: 2px;
            transition: width var(--transition-normal);
        }
        .header-nav .nav-links a:hover::after,
        .header-nav .nav-links a.active::after {
            width: 100%;
        }
        .header-nav .nav-cta {
            flex-shrink: 0;
            margin-left: 12px;
        }
        .header-nav .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            cursor: pointer;
            z-index: 1001;
            padding: 6px;
        }
        .header-nav .hamburger span {
            width: 26px;
            height: 2.5px;
            background: #ffffff;
            border-radius: 3px;
            transition: all var(--transition-normal);
            display: block;
        }
        .header-nav.scrolled .hamburger span {
            background: var(--color-primary);
        }
        .mobile-menu {
            display: none;
            position: fixed;
            top: var(--nav-height);
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(255, 255, 255, 0.97);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            z-index: 999;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 22px;
            padding: 40px 24px;
        }
        .mobile-menu.active {
            display: flex;
        }
        .mobile-menu a {
            font-size: 1.15rem;
            font-weight: 600;
            color: var(--color-text);
            transition: color var(--transition-fast);
        }
        .mobile-menu a:hover {
            color: var(--color-accent);
        }
        @media (max-width: 900px) {
            .header-nav .nav-links {
                display: none;
            }
            .header-nav .nav-cta {
                display: none;
            }
            .header-nav .hamburger {
                display: flex;
            }
        }

        .hero-section {
            position: relative;
            min-height: 100vh;
            display: flex;
            align-items: center;
            background: url('/assets/images/backpic/back-1.webp') center / cover no-repeat;
            background-position: center 30%;
            overflow: hidden;
        }
        .hero-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, rgba(7, 26, 46, 0.78) 0%, rgba(11, 45, 91, 0.55) 50%, rgba(7, 26, 46, 0.7) 100%);
            z-index: 1;
        }
        .hero-section .hero-content {
            position: relative;
            z-index: 2;
            max-width: 680px;
            padding: 100px 0 60px;
        }
        .hero-section .hero-content h1 {
            font-size: 3rem;
            font-weight: 800;
            color: #ffffff;
            line-height: 1.22;
            letter-spacing: -0.6px;
            margin-bottom: 16px;
        }
        .hero-section .hero-content h1 span {
            color: var(--color-accent);
        }
        .hero-section .hero-content .hero-subtitle {
            font-size: 1.15rem;
            color: rgba(255, 255, 255, 0.82);
            margin-bottom: 36px;
            line-height: 1.6;
            max-width: 520px;
        }
        .hero-section .hero-content .hero-btns {
            display: flex;
            gap: 14px;
            flex-wrap: wrap;
        }
        @media (max-width: 768px) {
            .hero-section .hero-content h1 {
                font-size: 2.1rem;
            }
            .hero-section .hero-content .hero-subtitle {
                font-size: 1rem;
            }
            .hero-section .hero-content {
                padding: 80px 0 40px;
            }
        }
        @media (max-width: 520px) {
            .hero-section .hero-content h1 {
                font-size: 1.7rem;
            }
            .hero-section .hero-content .hero-btns {
                flex-direction: column;
                align-items: flex-start;
            }
        }

        .dark-band {
            background: var(--color-dark);
            color: #ffffff;
        }
        .dark-band h2,
        .dark-band h3,
        .dark-band h4 {
            color: #ffffff;
        }
        .dark-band p {
            color: rgba(255, 255, 255, 0.7);
        }
        .dark-band .stat-card {
            background: rgba(255, 255, 255, 0.04);
            border: 1px solid rgba(255, 255, 255, 0.1);
            box-shadow: none;
        }
        .dark-band .stat-card .stat-number {
            color: var(--color-accent);
        }
        .dark-band .stat-card .stat-label {
            color: rgba(255, 255, 255, 0.6);
        }

        .bg-alt {
            background: var(--color-bg-alt);
        }

        .img-rounded {
            border-radius: var(--radius-lg);
            overflow: hidden;
        }
        .img-rounded img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .divider {
            width: 50px;
            height: 3px;
            background: var(--color-accent);
            border-radius: 3px;
            margin: 0 auto 20px;
        }

        @media (max-width: 1024px) {
            :root {
                --nav-height: 64px;
            }
        }