/* roulang page: index */
:root {
      --primary: #E8613C;
      --primary-deep: #D45530;
      --secondary: #1E3A4C;
      --accent: #D4A843;
      --bg-warm: #FAF8F5;
      --bg-light: #F0F3F5;
      --white: #FFFFFF;
      --text-main: #1E3A4C;
      --text-muted: #5F6B7A;
      --text-reverse: #FFFFFF;
      --border-light: #D0D5DB;
      --shadow-card: 0 4px 20px rgba(30,58,76,0.06);
      --shadow-card-hover: 0 10px 30px rgba(30,58,76,0.10);
      --shadow-nav: 0 2px 12px rgba(0,0,0,0.04);
      --radius-card: 12px;
      --radius-button: 8px;
      --radius-input: 6px;
      --font-ping: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --transition: 0.25s ease;
    }

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

    body {
      font-family: var(--font-ping);
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

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

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

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

    /* 导航 */
    #header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--white);
      box-shadow: none;
      transition: box-shadow 0.3s;
      height: 72px;
      display: flex;
      align-items: center;
    }

    #header.scrolled {
      box-shadow: var(--shadow-nav);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }

    .logo {
      font-size: 26px;
      font-weight: 700;
      color: var(--secondary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--primary);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-main);
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: var(--white);
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.5px;
      cursor: pointer;
      transition: 0.25s;
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--primary-deep);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(232,97,60,0.3);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--secondary);
      color: var(--secondary);
      padding: 12px 28px;
      border-radius: var(--radius-button);
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-outline:hover {
      background: var(--secondary);
      color: var(--white);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--secondary);
      border-radius: 4px;
      transition: 0.2s;
    }

    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background: var(--white);
        flex-direction: column;
        padding: 90px 30px 30px;
        gap: 28px;
        box-shadow: -5px 0 20px rgba(0,0,0,0.08);
        transition: right 0.3s ease;
        align-items: flex-start;
      }
      .nav-links.open {
        right: 0;
      }
      .hamburger {
        display: flex;
        z-index: 55;
      }
      .nav-links .btn-primary {
        width: 100%;
        text-align: center;
      }
    }

    /* Hero */
    #hero {
      padding: 90px 0 100px;
      background: var(--bg-warm);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-text h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--secondary);
      margin-bottom: 24px;
    }
    .hero-text .highlight {
      color: var(--primary);
    }
    .hero-sub {
      font-size: 20px;
      color: var(--text-muted);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      background: linear-gradient(135deg, rgba(232,97,60,0.08) 0%, rgba(30,58,76,0.05) 100%);
      min-height: 340px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-text h1 {
        font-size: 40px;
      }
      .hero-sub {
        margin-left: auto;
        margin-right: auto;
      }
      .hero-actions {
        justify-content: center;
      }
      .hero-image {
        min-height: 280px;
        order: -1;
        margin-bottom: 16px;
      }
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 38px;
      font-weight: 600;
      color: var(--secondary);
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      display: block;
      width: 40px;
      height: 3px;
      background: var(--primary);
      margin-top: 12px;
    }
    .section-desc {
      color: var(--text-muted);
      font-size: 17px;
      max-width: 600px;
    }
    .bg-alt {
      background: var(--bg-light);
    }
    .text-center {
      text-align: center;
    }

    /* 解决方案卡片 */
    #solutions .cards {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 48px;
    }
    .solution-card {
      background: var(--white);
      padding: 32px 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      border: 1px solid transparent;
    }
    .solution-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-card-hover);
      border-color: rgba(232,97,60,0.25);
    }
    .solution-icon {
      font-size: 42px;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .solution-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .solution-card p {
      color: var(--text-muted);
      margin-bottom: 16px;
    }
    .link-more {
      color: var(--primary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 优势 */
    #advantages .adv-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 36px;
      margin-top: 40px;
    }
    .adv-item {
      text-align: center;
    }
    .adv-number {
      font-size: 52px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .adv-label {
      color: var(--text-muted);
      font-size: 15px;
    }

    /* 案例 */
    #cases .case-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
      margin-top: 48px;
    }
    .case-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: 0.2s;
    }
    .case-img {
      aspect-ratio: 16/9;
      background: #e9edf2;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: 0.3s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.03);
    }
    .case-content {
      padding: 20px;
    }
    .tag {
      font-size: 12px;
      color: var(--accent);
      border: 1px solid var(--accent);
      display: inline-block;
      padding: 2px 10px;
      border-radius: 20px;
      margin-bottom: 8px;
    }

    /* 流程 */
    #process .steps {
      display: flex;
      justify-content: space-between;
      margin-top: 48px;
      position: relative;
    }
    .step {
      text-align: center;
      flex:1;
    }
    .step-num {
      width: 48px;
      height: 48px;
      background: var(--primary);
      color: white;
      border-radius: 50%;
      margin: 0 auto 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 20px;
    }
    .step-title {
      font-weight: 600;
      margin-bottom: 6px;
    }
    @media(max-width:768px){
      .steps{flex-direction: column; gap:24px;}
    }

    /* FAQ */
    .faq-item {
      background: var(--white);
      border-radius: 10px;
      margin-bottom: 16px;
      padding: 0 20px;
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
      border: 1px solid #eef1f4;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      color: var(--secondary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.35s ease;
      color: var(--text-muted);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 18px;
    }

    /* 联系 */
    #contact {
      background: var(--secondary);
      color: var(--white);
    }
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      margin-top: 32px;
    }
    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 12px 16px;
      border-radius: var(--radius-input);
      border: 1px solid var(--border-light);
      margin-bottom: 16px;
    }
    .contact-info p {
      margin: 12px 0;
    }

    footer {
      background: var(--secondary);
      color: rgba(255,255,255,0.7);
      padding: 24px 0;
      text-align: center;
      border-top: 1px solid rgba(255,255,255,0.1);
    }