/* roulang page: index */
:root {
            --primary: #E10600;
            --primary-hover: #ff1a14;
            --secondary: #1A1A2E;
            --accent: #00F0FF;
            --bg-deep: #0D0D1A;
            --bg-card: rgba(26, 26, 46, 0.8);
            --text-main: #f0f0f5;
            --text-muted: #b0b0c0;
            --text-weak: #888;
            --border-light: rgba(0, 240, 255, 0.15);
            --border-hover: rgba(0, 240, 255, 0.45);
            --shadow-card: 0 4px 24px rgba(0, 240, 255, 0.08);
            --shadow-hover: 0 12px 32px rgba(0, 240, 255, 0.25);
            --radius-md: 8px;
            --radius-sm: 6px;
            --font-title: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
            --font-body: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
            --font-number: 'DIN Alternate', 'PingFang SC', sans-serif;
            --container-max: 1280px;
            --section-gap: 110px;
            --card-gap: 24px;
            --nav-height: 72px;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            background-color: var(--bg-deep);
        }
        body {
            font-family: var(--font-body);
            background: var(--bg-deep);
            color: var(--text-main);
            line-height: 1.5;
            font-weight: 400;
            min-height: 100vh;
            -webkit-font-smoothing: antialiased;
        }
        a {
            text-decoration: none;
            color: inherit;
            transition: color 0.2s ease, background 0.2s ease;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        button, .btn {
            cursor: pointer;
            font-family: var(--font-body);
            border: none;
            outline: none;
            transition: all 0.25s ease;
        }
        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
        }
        @media (max-width: 767px) {
            .container {
                padding: 0 16px;
            }
            :root {
                --section-gap: 70px;
            }
        }

        /* 导航 */
        .site-nav {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--nav-height);
            background: rgba(13, 13, 26, 0.88);
            backdrop-filter: blur(14px);
            -webkit-backdrop-filter: blur(14px);
            border-bottom: 1px solid rgba(0, 240, 255, 0.2);
            z-index: 999;
            display: flex;
            align-items: center;
            transition: background 0.3s;
        }
        .site-nav.scrolled {
            background: rgba(13, 13, 26, 0.97);
            border-bottom-color: rgba(0, 240, 255, 0.35);
        }
        .nav-container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
        }
        .logo {
            font-family: var(--font-title);
            font-weight: 800;
            font-size: 1.7rem;
            letter-spacing: 1px;
            color: #fff;
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .logo .red {
            color: var(--primary);
        }
        .logo .slash {
            color: var(--accent);
            font-weight: 600;
            margin: 0 2px;
        }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 2.2rem;
        }
        .nav-links a {
            color: #ddd;
            font-weight: 500;
            font-size: 1rem;
            position: relative;
            padding: 4px 0;
        }
        .nav-links a:hover,
        .nav-links a.active {
            color: var(--accent);
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0%;
            height: 2px;
            background: var(--accent);
            transition: width 0.25s;
        }
        .nav-links a:hover::after {
            width: 100%;
        }
        .btn-nav {
            background: var(--primary);
            color: #fff;
            padding: 10px 22px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 0.95rem;
            box-shadow: 0 0 12px rgba(225, 6, 0, 0.5);
        }
        .btn-nav:hover {
            background: var(--primary-hover);
            box-shadow: 0 0 22px rgba(225, 6, 0, 0.8);
            transform: translateY(-1px);
        }
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            background: transparent;
            border: none;
            width: 32px;
            height: 24px;
            justify-content: center;
        }
        .hamburger span {
            display: block;
            width: 100%;
            height: 2.5px;
            background: #ddd;
            border-radius: 2px;
            transition: 0.3s;
        }
        .hamburger:hover span {
            background: var(--accent);
        }
        .mobile-menu {
            display: none;
            position: fixed;
            top: var(--nav-height);
            left: 0;
            width: 100%;
            background: rgba(8, 8, 18, 0.98);
            backdrop-filter: blur(20px);
            padding: 20px;
            flex-direction: column;
            gap: 18px;
            border-bottom: 1px solid var(--border-light);
            z-index: 998;
        }
        .mobile-menu a {
            font-size: 1.2rem;
            font-weight: 600;
            color: #ddd;
            padding: 10px 0;
            border-left: 4px solid transparent;
            padding-left: 12px;
        }
        .mobile-menu a:hover {
            color: var(--accent);
            border-left-color: var(--accent);
        }
        @media (max-width: 1023px) {
            .nav-links { display: none; }
            .hamburger { display: flex; }
        }

        /* 通用标题 */
        h1, h2, h3 {
            font-family: var(--font-title);
        }
        .section-title {
            font-size: 2.25rem;
            font-weight: 700;
            margin-bottom: 1.8rem;
            letter-spacing: 0.5px;
        }
        .section-title .accent {
            color: var(--accent);
        }
        @media (max-width: 767px) {
            .section-title {
                font-size: 1.8rem;
            }
        }

        /* Hero */
        #hero {
            height: 100vh;
            min-height: 650px;
            background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
            position: relative;
            display: flex;
            align-items: center;
        }
        .hero-overlay {
            position: absolute;
            inset: 0;
            background: radial-gradient(circle at 30% 30%, rgba(13,13,26,0.5) 0%, #0D0D1A 95%);
        }
        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 700px;
            margin-left: 8%;
        }
        .hero h1 {
            font-size: 3.4rem;
            font-weight: 800;
            line-height: 1.25;
            text-shadow: 0 0 25px rgba(0,240,255,0.3);
            margin-bottom: 1.2rem;
        }
        .hero p {
            font-size: 1.2rem;
            color: #ccc;
            margin-bottom: 2.2rem;
            max-width: 500px;
        }
        .btn-primary {
            background: var(--primary);
            color: #fff;
            padding: 14px 38px;
            font-weight: 700;
            font-size: 1.1rem;
            border-radius: var(--radius-sm);
            box-shadow: 0 0 22px rgba(225, 6, 0, 0.7);
            display: inline-block;
        }
        .btn-primary:hover {
            background: #ff2a24;
            box-shadow: 0 0 35px rgba(225, 6, 0, 0.9);
            transform: translateY(-2px);
        }
        @media (max-width: 1023px) {
            .hero h1 { font-size: 2.5rem; }
            .hero-content { margin-left: 5%; }
        }
        @media (max-width: 767px) {
            .hero h1 { font-size: 2rem; }
            .hero p { font-size: 1rem; }
        }

        /* 区块 */
        section {
            padding: var(--section-gap) 0;
        }
        .bg-alt {
            background: rgba(255,255,255,0.02);
        }

        /* 核心优势 非对称三列 */
        .features-grid {
            display: grid;
            grid-template-columns: 1.3fr 0.85fr 0.85fr;
            gap: var(--card-gap);
            margin-top: 2rem;
        }
        .feature-card {
            background: var(--bg-card);
            border: 1px solid var(--border-light);
            border-radius: var(--radius-md);
            padding: 2rem 1.8rem;
            box-shadow: var(--shadow-card);
            transition: all 0.3s;
        }
        .feature-card:hover {
            border-color: var(--border-hover);
            box-shadow: var(--shadow-hover);
            transform: translateY(-5px);
        }
        .feature-icon {
            font-size: 2.8rem;
            color: var(--accent);
            margin-bottom: 1.2rem;
        }
        .feature-card h3 {
            font-size: 1.4rem;
            margin-bottom: 0.7rem;
        }
        @media (max-width: 1023px) {
            .features-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media (max-width: 767px) {
            .features-grid {
                grid-template-columns: 1fr;
            }
        }

        /* 场景 2x2 */
        .scenarios-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: var(--card-gap);
        }
        .scenario-card {
            background: var(--bg-card);
            border: 1px solid var(--border-light);
            border-radius: var(--radius-md);
            overflow: hidden;
            transition: 0.3s;
        }
        .scenario-card:hover {
            border-color: var(--border-hover);
            box-shadow: var(--shadow-hover);
            transform: translateY(-4px);
        }
        .scenario-img {
            height: 180px;
            background-size: cover;
            background-position: center;
        }
        .scenario-body {
            padding: 1.5rem;
        }
        @media (max-width: 767px) {
            .scenarios-grid { grid-template-columns: 1fr; }
        }

        /* 案例 横向滚动 */
        .cases-scroll {
            display: flex;
            gap: var(--card-gap);
            overflow-x: auto;
            padding-bottom: 12px;
            scrollbar-width: thin;
        }
        .case-card {
            flex: 0 0 300px;
            background: var(--bg-card);
            border: 1px solid var(--border-light);
            border-radius: var(--radius-md);
            padding: 1.5rem;
        }
        .case-number {
            font-family: var(--font-number);
            font-size: 2.5rem;
            font-weight: 700;
            color: var(--primary);
        }

        /* FAQ 手风琴 */
        .faq-layout {
            display: flex;
            gap: 2rem;
        }
        .faq-left {
            flex: 0 0 28%;
        }
        .faq-right {
            flex: 1;
        }
        .faq-item {
            background: rgba(26,26,46,0.7);
            border: 1px solid rgba(0,240,255,0.12);
            border-radius: var(--radius-sm);
            margin-bottom: 12px;
            padding: 1rem 1.3rem;
            cursor: pointer;
            transition: 0.25s;
        }
        .faq-item.active {
            border-left: 4px solid var(--primary);
            border-color: rgba(0,240,255,0.35);
        }
        @media (max-width: 767px) {
            .faq-layout { flex-direction: column; }
        }

        /* CTA */
        #cta {
            background: #0A0A16;
            box-shadow: inset 0 0 40px rgba(0,240,255,0.15);
            text-align: center;
        }
        .btn-outline {
            border: 1.5px solid var(--accent);
            color: var(--accent);
            background: transparent;
            padding: 12px 34px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            margin-left: 16px;
        }
        .btn-outline:hover {
            background: rgba(0,240,255,0.1);
        }

        /* Footer */
        .footer-grid {
            display: grid;
            grid-template-columns: 1.5fr 1fr 1fr 1fr;
            gap: 2rem;
        }
        @media (max-width: 767px) {
            .footer-grid { grid-template-columns: 1fr; }
        }
        .copyright {
            text-align: center;
            color: #666;
            margin-top: 2.5rem;
        }