/* roulang page: index */
:root {
      --deep-blue: #0B4F6C;
      --coral-orange: #F27A54;
      --coral-hover: #E0693F;
      --coral-active: #C95A35;
      --warm-white: #FAFBFD;
      --ice-blue: #F0F4F8;
      --pure-white: #FFFFFF;
      --dark-ink: #1A2B3C;
      --slate-gray: #4A5568;
      --light-blue-gray: #8899AA;
      --border-light: #E2E8F0;
      --sea-green: #38A169;
      --shadow-card: 0 2px 12px rgba(11, 79, 108, 0.06);
      --shadow-card-hover: 0 8px 24px rgba(11, 79, 108, 0.12);
      --shadow-nav: 0 1px 4px rgba(0,0,0,0.04);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-number: "Inter", system-ui, -apple-system;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--warm-white);
      color: var(--slate-gray);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      color: var(--dark-ink);
      letter-spacing: -0.3px;
    }

    h1 {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
    }
    h2 {
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 600;
      line-height: 1.4;
    }
    h4 {
      font-size: 1.15rem;
      font-weight: 600;
      line-height: 1.5;
    }

    .text-muted-custom {
      color: var(--light-blue-gray) !important;
    }

    /* 容器微调 */
    .container-lg {
      max-width: 1200px;
      padding-left: 20px;
      padding-right: 20px;
    }

    /* 导航栏 */
    .navbar {
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      box-shadow: var(--shadow-nav);
      height: 72px;
      transition: all 0.25s ease;
      padding: 0 1rem;
    }
    .navbar.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }
    .navbar-brand {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--deep-blue) !important;
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 0.5px;
    }
    .logo-icon {
      font-size: 1.8rem;
      color: var(--deep-blue);
    }
    .navbar-nav .nav-link {
      color: var(--slate-gray) !important;
      font-weight: 500;
      margin: 0 0.5rem;
      position: relative;
      transition: color 0.2s;
      padding: 0.5rem 0;
    }
    .navbar-nav .nav-link:hover,
    .navbar-nav .nav-link.active {
      color: var(--deep-blue) !important;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--coral-orange);
      transition: all 0.2s ease;
      transform: translateX(-50%);
    }
    .nav-link:hover::after {
      width: 100%;
    }
    .btn-nav-cta {
      background: var(--coral-orange);
      color: white !important;
      border-radius: 8px;
      padding: 10px 24px !important;
      font-weight: 600;
      transition: background 0.2s;
      margin-left: 12px;
      border: none;
    }
    .btn-nav-cta:hover {
      background: var(--coral-hover);
    }
    .navbar-toggler {
      border: none;
      color: var(--slate-gray);
      font-size: 1.5rem;
    }
    .navbar-toggler:focus {
      box-shadow: 0 0 0 2px var(--coral-orange);
    }

    @media (max-width: 991px) {
      .navbar {
        height: 60px;
      }
      .navbar-collapse {
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(12px);
        padding: 1rem;
        border-radius: 0 0 12px 12px;
        box-shadow: 0 8px 20px rgba(0,0,0,0.05);
      }
      .navbar-nav {
        text-align: center;
      }
      .btn-nav-cta {
        margin: 10px auto 0;
        display: inline-block;
        width: auto;
      }
    }

    /* Hero */
    #hero {
      padding: 120px 0;
      position: relative;
      background: radial-gradient(circle at 20% 30%, rgba(11,79,108,0.02) 0%, transparent 50%);
    }
    .hero-title {
      font-size: 3rem;
      font-weight: 700;
      color: var(--dark-ink);
    }
    .hero-subtitle {
      font-size: 1.25rem;
      color: var(--slate-gray);
      max-width: 520px;
    }
    .hero-image {
      width: 100%;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(11,79,108,0.12);
      transition: transform 0.3s;
    }
    .btn-primary-custom {
      background: var(--coral-orange);
      border: none;
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: 8px;
      transition: all 0.2s;
    }
    .btn-primary-custom:hover {
      background: var(--coral-hover);
      color: white;
    }
    .btn-outline-custom {
      background: transparent;
      border: 2px solid var(--deep-blue);
      color: var(--deep-blue);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: 8px;
      transition: all 0.2s;
    }
    .btn-outline-custom:hover {
      background: var(--deep-blue);
      color: white;
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-weight: 700;
      margin-bottom: 1.5rem;
    }
    .bg-light-ice {
      background-color: var(--ice-blue);
    }
    .bg-deep-blue {
      background-color: var(--deep-blue);
      color: white;
    }

    /* 痛点卡片 */
    .problem-card {
      background: var(--pure-white);
      border-radius: 12px;
      padding: 28px 24px;
      box-shadow: var(--shadow-card);
      border-left: 3px solid #E2E8F0;
      transition: all 0.25s;
      height: 100%;
    }
    .problem-card:hover {
      border-left-color: var(--coral-orange);
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .icon-circle {
      font-size: 24px;
      color: var(--deep-blue);
      margin-bottom: 15px;
    }

    /* 解决方案交替布局 */
    .solution-img {
      border-radius: 16px;
      box-shadow: 0 18px 30px rgba(0,0,0,0.08);
      width: 100%;
      height: auto;
    }
    .feature-check li {
      list-style: none;
      margin-bottom: 8px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .feature-check i {
      color: var(--sea-green);
    }

    /* 优势卡片 */
    .advantage-card {
      background: var(--pure-white);
      border: 1px solid var(--border-light);
      border-radius: 12px;
      overflow: hidden;
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      transition: all 0.2s;
    }
    .advantage-card:hover {
      border-color: var(--deep-blue);
      box-shadow: var(--shadow-card-hover);
    }
    .advantage-img {
      height: 160px;
      object-fit: cover;
      width: 100%;
    }

    /* 成果数据 */
    .data-number {
      font-family: var(--font-number);
      font-size: 3rem;
      font-weight: 800;
      color: var(--deep-blue);
    }
    .bg-gradient-light {
      background: linear-gradient(135deg, #F0F4F8 0%, #FAFBFD 100%);
      border-radius: 16px;
    }

    /* 证言 */
    .testimonial-card {
      background: white;
      border-radius: 12px;
      padding: 24px;
      border-left: 4px solid var(--deep-blue);
      box-shadow: var(--shadow-card);
    }
    .testimonial-text {
      font-style: italic;
      line-height: 1.7;
    }

    /* FAQ */
    .accordion-button {
      font-weight: 600;
      background: white;
      color: var(--dark-ink);
      box-shadow: none;
      border-radius: 8px !important;
    }
    .accordion-button:not(.collapsed) {
      background-color: var(--ice-blue);
      color: var(--deep-blue);
    }
    .accordion-button:focus {
      border-color: var(--deep-blue);
      box-shadow: 0 0 0 3px rgba(11,79,108,0.1);
    }

    /* CTA */
    .btn-cta-large {
      background: white;
      color: var(--deep-blue);
      font-weight: 700;
      padding: 16px 42px;
      border-radius: 50px;
      font-size: 1.2rem;
      transition: 0.2s;
      border: none;
    }
    .btn-cta-large:hover {
      background: #f0f0f0;
    }

    /* 页脚 */
    footer {
      background: var(--deep-blue);
      color: rgba(255,255,255,0.8);
      padding-top: 60px;
    }
    footer a {
      color: rgba(255,255,255,0.8);
      text-decoration: none;
      transition: 0.2s;
    }
    footer a:hover {
      color: white;
      padding-left: 4px;
    }
    .footer-social i {
      font-size: 1.5rem;
      margin-right: 15px;
      color: white;
      transition: 0.2s;
    }
    .footer-social i:hover {
      color: var(--coral-orange);
    }
    .copyright {
      background: #093D55;
      font-size: 0.9rem;
    }

    @media (max-width: 768px) {
      h1 { font-size: 2rem; }
      h2 { font-size: 1.75rem; }
      #hero { padding: 80px 0; }
      section { padding: 70px 0; }
    }