/* roulang page: index */
:root {
      --primary: #E8451E;
      --primary-dark: #C03814;
      --secondary: #1A1C20;
      --accent: #00C2A8;
      --neutral-bg: #F4F5F7;
      --gray-mid: #6B7280;
      --gray-light: #E5E7EB;
      --white: #FFFFFF;
      --card-shadow: 0 4px 12px rgba(0,0,0,0.04);
      --card-shadow-hover: 0 12px 28px rgba(0,0,0,0.08);
      --border-light: 1px solid rgba(0,0,0,0.06);
      --radius-lg: 12px;
      --radius-md: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition-smooth: 0.3s ease;
      --max-width: 1280px;
      --section-gap: 100px;
    }

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

    body {
      font-family: var(--font-sans);
      font-weight: 400;
      line-height: 1.7;
      color: #4B5563;
      background-color: #F9FAFB;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

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

    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }

    /* 导航样式 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      padding: 16px 0;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
    }

    #nav.scrolled {
      background: var(--white);
      box-shadow: 0 2px 20px rgba(0,0,0,0.06);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--white);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }

    #nav.scrolled .logo {
      color: var(--secondary);
    }

    .logo i {
      color: var(--primary);
      font-size: 1.8rem;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: rgba(255,255,255,0.9);
      transition: color 0.2s;
      white-space: nowrap;
    }

    #nav.scrolled .nav-links a {
      color: var(--secondary);
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 22px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.9rem;
      transition: background 0.3s, transform 0.2s;
    }

    .nav-cta:hover {
      background: var(--primary-dark);
      transform: translateY(-1px);
    }

    .burger {
      display: none;
      font-size: 1.8rem;
      color: white;
      background: none;
      border: none;
      cursor: pointer;
    }

    #nav.scrolled .burger {
      color: var(--secondary);
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: var(--secondary);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 36px;
      z-index: 1000;
    }

    .mobile-menu.active {
      display: flex;
    }

    .mobile-menu a {
      color: white;
      font-size: 1.5rem;
      font-weight: 500;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .burger {
        display: block;
      }
    }

    /* Hero */
    #hero {
      background: var(--secondary);
      min-height: 90vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding: 100px 0 80px;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 40px;
      align-items: center;
    }

    .hero-text {
      color: white;
      z-index: 2;
    }

    .hero-text h1 {
      font-size: clamp(2.4rem, 6vw, 3.8rem);
      font-weight: 700;
      line-height: 1.15;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero-text .sub {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: 0.3s;
      display: inline-block;
      box-shadow: 0 4px 12px rgba(232,69,30,0.3);
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(232,69,30,0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 600;
      transition: 0.3s;
      display: inline-block;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .hero-image {
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      aspect-ratio: 16 / 10;
      z-index: 2;
    }

    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-image {
        order: -1;
        aspect-ratio: 4/3;
      }
      .btn-group .btn-primary, .btn-group .btn-outline {
        width: 100%;
        text-align: center;
      }
    }

    /* 板块通用 */
    section {
      padding: var(--section-gap) 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      color: var(--secondary);
      margin-bottom: 16px;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .highlight-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-lg);
      box-shadow: var(--card-shadow);
      text-align: center;
      transition: var(--transition-smooth);
    }

    .highlight-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-shadow-hover);
    }

    .highlight-icon {
      font-size: 2.2rem;
      color: var(--accent);
      margin-bottom: 16px;
    }

    @media (max-width: 1024px) {
      .highlights-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 520px) {
      .highlights-grid { grid-template-columns: 1fr; }
    }

    /* 案例瀑布 */
    .cases-masonry {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .case-card {
      background: var(--white);
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--card-shadow);
      transition: 0.3s;
    }

    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--card-shadow-hover);
    }

    .case-img {
      aspect-ratio: 16/10;
      background-size: cover;
      background-position: center;
    }

    .case-info {
      padding: 20px;
    }

    .case-tag {
      background: #FEE2E2;
      color: var(--primary);
      font-size: 0.75rem;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 8px;
    }

    @media (max-width: 768px) {
      .cases-masonry { grid-template-columns: 1fr; }
    }

    /* 对比表 */
    .compare-table {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .plan-card {
      background: white;
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      text-align: center;
      border: 1px solid var(--gray-light);
    }

    .plan-card.recommended {
      border: 2px solid var(--primary);
      background: #FFF5F3;
      position: relative;
      transform: scale(1.02);
    }

    .badge {
      background: var(--primary);
      color: white;
      padding: 4px 16px;
      border-radius: 20px;
      font-size: 0.8rem;
      position: absolute;
      top: -12px;
      left: 50%;
      transform: translateX(-50%);
    }

    @media (max-width: 768px) {
      .compare-table { grid-template-columns: 1fr; }
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      border: 1px solid var(--gray-light);
    }

    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #FAFBFC;
      padding: 0 24px;
    }

    .faq-answer.open {
      max-height: 200px;
      padding: 20px 24px;
    }

    /* CTA */
    #contact {
      background: linear-gradient(135deg, #E8451E, #C03814);
      color: white;
    }

    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 14px;
      border-radius: 8px;
      border: none;
      margin-bottom: 16px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr; }
    }