/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #0A4C6B;
      --primary-hover: #083C54;
      --accent: #FF6F4C;
      --accent-hover: #E65A3A;
      --bg: #F7F9FC;
      --card-bg: #FFFFFF;
      --text-main: #1E2A38;
      --text-secondary: #5F6B7A;
      --success: #1FA089;
      --border-light: #E9EDF4;
      --shadow-sm: 0 4px 20px rgba(10, 76, 107, 0.06);
      --shadow-md: 0 8px 30px rgba(10, 76, 107, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition: 0.25s ease;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.7;
      font-weight: 400;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    button, .btn {
      cursor: pointer;
      border: none;
      outline: none;
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
      body {
        font-size: 0.95rem;
      }
    }

    /* 导航栏 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.94);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(10,76,107,0.08);
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 70px;
    }
    .logo {
      font-weight: 700;
      font-size: 1.6rem;
      letter-spacing: 0.5px;
      color: var(--primary);
    }
    .logo span {
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-main);
      transition: color var(--transition);
      font-size: 0.95rem;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .btn-nav-cta {
      background: var(--accent);
      color: white !important;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background var(--transition), box-shadow var(--transition);
      box-shadow: 0 4px 10px rgba(255,111,76,0.25);
    }
    .btn-nav-cta:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 16px rgba(255,111,76,0.4);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      background: none;
      border: none;
      color: var(--text-main);
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 1.5rem;
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 300px;
        height: 100vh;
        background: white;
        flex-direction: column;
        padding: 5rem 2rem 2rem;
        gap: 2.2rem;
        box-shadow: -8px 0 30px rgba(0,0,0,0.08);
        transition: right 0.3s ease;
        align-items: flex-start;
        z-index: 100;
      }
      .nav-links.active {
        right: 0;
      }
      .hamburger {
        display: block;
        z-index: 110;
      }
      .nav-links .close-menu {
        position: absolute;
        top: 20px;
        right: 20px;
        font-size: 2rem;
        background: none;
        border: none;
        color: var(--text-main);
      }
    }

    /* 通用板块间距 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 56px 0;
      }
    }

    /* 标题层级 */
    h1 {
      font-size: 2.5rem;
      line-height: 1.2;
      font-weight: 700;
      color: var(--text-main);
    }
    h2 {
      font-size: 2rem;
      line-height: 1.3;
      font-weight: 700;
      margin-bottom: 1.2rem;
    }
    h3 {
      font-size: 1.5rem;
      line-height: 1.4;
      font-weight: 600;
    }
    @media (max-width: 768px) {
      h1 { font-size: 2rem; }
      h2 { font-size: 1.7rem; }
      h3 { font-size: 1.3rem; }
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-block;
      transition: background var(--transition), box-shadow var(--transition);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: var(--shadow-md);
    }
    .btn-accent {
      background: var(--accent);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      display: inline-block;
      animation: pulse-shadow 2s infinite;
      transition: background var(--transition);
    }
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    @keyframes pulse-shadow {
      0% { box-shadow: 0 0 0 0 rgba(255,111,76,0.5); }
      70% { box-shadow: 0 0 0 12px rgba(255,111,76,0); }
      100% { box-shadow: 0 0 0 0 rgba(255,111,76,0); }
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all var(--transition);
    }
    .btn-outline:hover {
      background: rgba(10,76,107,0.04);
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
    }

    /* 痛点卡片左色条 */
    .pain-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      padding: 1.8rem;
      box-shadow: var(--shadow-sm);
      border-left: 5px solid var(--accent);
      transition: var(--transition);
    }
    .pain-card:hover {
      box-shadow: var(--shadow-md);
    }

    /* 数字统计块 */
    .stat-number {
      font-size: 2.6rem;
      font-weight: 700;
      color: var(--success);
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      text-align: left;
      padding: 1.2rem 0;
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-main);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      padding-right: 1rem;
    }
    .faq-answer.open {
      max-height: 200px;
      padding-bottom: 1rem;
    }

    footer {
      background: #1E2A38;
      color: #CBD5E1;
      padding: 48px 0 20px;
    }
    footer a:hover {
      color: white;
    }