/* roulang page: index */
:root {
      --primary: #E63946;
      --primary-dark: #c62d39;
      --secondary: #1D3557;
      --secondary-dark: #0B1E3F;
      --accent: #F4A261;
      --accent-light: #f7b27a;
      --neutral-bg: #F1FAEE;
      --neutral-light: #EDF2F4;
      --text-dark: #2B2D42;
      --text-muted: #8D99AE;
      --white: #FFFFFF;
      --card-bg: #F8F9FA;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --shadow-lg: 0 16px 40px rgba(0,0,0,0.12);
      --shadow-xl: 0 24px 56px rgba(0,0,0,0.18);
      --radius-xs: 6px;
      --radius-sm: 10px;
      --radius-md: 16px;
      --radius-lg: 20px;
      --radius-xl: 24px;
      --transition: 0.25s ease-out;
      --font-oswald: 'Oswald', sans-serif;
      --font-sans: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --container: 1200px;
      --spacing-xs: 8px;
      --spacing-sm: 16px;
      --spacing-md: 24px;
      --spacing-lg: 40px;
      --spacing-xl: 64px;
      --spacing-2xl: 100px;
      --spacing-3xl: 140px;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-dark);
      line-height: 1.6;
      font-size: 16px;
      min-height: 100vh;
      display: flex;
      flex-direction: column;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 600;
      border: none;
      background: none;
      transition: all var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }

    .container {
      width: 100%;
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 16px 0;
      transition: background 0.3s, padding 0.3s, box-shadow 0.3s;
      background: transparent;
    }
    .header.scrolled {
      background: rgba(29, 53, 87, 0.88);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      box-shadow: 0 8px 24px rgba(0,0,0,0.2);
      padding: 10px 0;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 20px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--white);
      display: flex;
      align-items: center;
      gap: 8px;
      text-shadow: 0 2px 8px rgba(0,0,0,0.3);
    }
    .logo i {
      font-size: 2rem;
      color: var(--accent);
      filter: drop-shadow(0 2px 4px rgba(0,0,0,0.4));
    }
    .header.scrolled .logo {
      text-shadow: none;
    }
    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.3s;
    }
    .nav-links a:hover {
      color: var(--white);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .btn-nav {
      background: var(--primary);
      color: var(--white) !important;
      padding: 10px 22px;
      border-radius: 50px;
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(230,57,70,0.35);
    }
    .btn-nav:hover {
      background: var(--accent);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(244,162,97,0.4);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--white);
      background: none;
      border: none;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
    }
    @media (max-width: 768px) {
      .hamburger {
        display: block;
      }
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background: var(--secondary-dark);
        flex-direction: column;
        padding: 100px 30px 40px;
        gap: 24px;
        transition: right 0.4s ease;
        box-shadow: -10px 0 30px rgba(0,0,0,0.5);
        backdrop-filter: blur(16px);
        background: rgba(11,30,63,0.95);
      }
      .nav-links.active {
        right: 0;
      }
      .nav-links a {
        font-size: 1.3rem;
        font-weight: 600;
      }
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, rgba(29,53,87,0.88) 0%, rgba(11,30,63,0.92) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      padding: 140px 0 80px;
      color: var(--white);
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 50px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 55%;
    }
    .hero-text h1 {
      font-size: clamp(2.8rem, 6vw, 3.8rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
      letter-spacing: -0.5px;
      text-shadow: 0 4px 20px rgba(0,0,0,0.4);
    }
    .hero-text .highlight {
      color: var(--accent);
    }
    .hero-desc {
      font-size: 1.2rem;
      margin-bottom: 36px;
      opacity: 0.92;
      max-width: 550px;
      line-height: 1.7;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: white;
      padding: 16px 40px;
      border-radius: 50px;
      font-size: 1.2rem;
      font-weight: 700;
      box-shadow: 0 10px 24px rgba(230,57,70,0.4);
      letter-spacing: 1px;
    }
    .btn-primary:hover {
      filter: brightness(1.1);
      transform: scale(1.03);
      box-shadow: 0 16px 32px rgba(230,57,70,0.55);
    }
    .hero-visual {
      flex: 1 1 40%;
      position: relative;
      display: flex;
      justify-content: center;
    }
    .floating-badge {
      background: rgba(255,255,255,0.1);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: var(--radius-lg);
      padding: 16px 30px;
      font-family: var(--font-oswald);
      color: var(--accent);
      font-size: 2.8rem;
      font-weight: 800;
      box-shadow: 0 15px 35px rgba(0,0,0,0.4);
      position: absolute;
      bottom: 20px;
      right: 0;
    }
    @media (max-width: 768px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
      }
      .hero-text {
        text-align: center;
      }
      .hero-desc {
        margin-left: auto;
        margin-right: auto;
      }
      .floating-badge {
        position: static;
        margin-top: 20px;
      }
    }

    /* 通用板块 */
    .section {
      padding: var(--spacing-3xl) 0;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 16px;
      color: var(--text-dark);
    }
    .section-sub {
      text-align: center;
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto 60px;
    }

    /* 优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 32px 28px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
      border: 1px solid rgba(0,0,0,0.03);
      display: flex;
      flex-direction: column;
      align-items: flex-start;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(230,57,70,0.2);
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .feature-badge {
      font-family: var(--font-oswald);
      font-size: 2.6rem;
      color: var(--accent);
      font-weight: 800;
      margin: 12px 0;
    }
    @media (max-width: 1024px) {
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 600px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 服务 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-md);
      transition: all 0.3s;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-xl);
    }
    .service-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    .service-body {
      padding: 24px;
    }
    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: repeat(2,1fr);
      }
    }
    @media (max-width: 600px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 场景交替 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 100px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-lg);
    }
    .scenario-text {
      flex: 1;
    }
    @media (max-width: 768px) {
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
      }
    }

    /* FAQ */
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-md);
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 28px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      background: var(--neutral-light);
      transition: 0.2s;
    }
    .faq-answer {
      padding: 0 28px 20px;
      color: var(--text-muted);
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active .faq-question {
      background: #fff;
      color: var(--primary);
    }

    /* CTA */
    .cta-band {
      background: linear-gradient(rgba(29,53,87,0.9), rgba(11,30,63,0.95)), url('/assets/images/backpic/back-2.webp') center/cover;
      padding: 100px 0;
      text-align: center;
      color: white;
    }
    .btn-outline-light {
      border: 2px solid white;
      color: white;
      padding: 14px 36px;
      border-radius: 50px;
      font-weight: 600;
    }
    .btn-outline-light:hover {
      background: white;
      color: var(--primary);
    }

    footer {
      background: var(--secondary-dark);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }