/* roulang page: index */
:root {
      --primary-graphite: #1A1D23;
      --accent-champagne: #C5A87E;
      --highlight-teal: #2C8C7C;
      --bg-warm: #F9F8F6;
      --card-bg: #FFFFFF;
      --border-light: #E8E5DF;
      --dark-bg: #15171C;
      --text-primary: #1A1D23;
      --text-secondary: #5A5D63;
      --text-muted: #8F9298;
      --text-inverse: #F0EFEC;
      --shadow-sm: 0 2px 12px rgba(26,29,35,0.04);
      --shadow-hover: 0 8px 28px rgba(26,29,35,0.08);
      --border-radius-card: 12px;
      --border-radius-btn: 8px;
      --border-radius-input: 6px;
      --border-radius-lg: 16px;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --font-heading: 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-number: 'Inter', 'SF Mono', 'PingFang SC', sans-serif;
      --font-en: 'Inter', sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm);
      color: var(--text-primary);
      line-height: 1.75;
      margin: 0;
      overflow-x: hidden;
    }

    h1, h2, h3, h4, h5, h6 {
      font-family: var(--font-heading);
      letter-spacing: -0.02em;
      font-weight: 700;
    }

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

    .accent-underline {
      text-decoration: underline;
      text-decoration-color: var(--highlight-teal);
      text-underline-offset: 4px;
    }
    .accent-underline:hover {
      text-decoration-color: var(--accent-champagne);
    }

    /* 左侧导航桌面 */
    .side-nav {
      position: fixed;
      left: 0;
      top: 0;
      width: 80px;
      height: 100vh;
      background: var(--primary-graphite);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      padding: 32px 0;
      z-index: 1030;
      border-right: 1px solid #2A2D33;
      transition: transform 0.2s;
    }

    .logo-area {
      writing-mode: vertical-rl;
      text-orientation: mixed;
      font-family: var(--font-heading);
      color: var(--accent-champagne);
      font-weight: 700;
      font-size: 1.2rem;
      letter-spacing: 0.1em;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo-area i {
      writing-mode: horizontal-tb;
      font-size: 1.8rem;
      color: var(--accent-champagne);
    }

    .nav-icons {
      display: flex;
      flex-direction: column;
      gap: 28px;
      list-style: none;
      padding: 0;
      margin: 0;
    }
    .nav-icons a {
      color: var(--text-muted);
      font-size: 1.4rem;
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      transition: color var(--transition-smooth);
    }
    .nav-icons a:hover,
    .nav-icons a.active {
      color: var(--highlight-teal);
    }
    .nav-icons a::after {
      content: attr(data-label);
      position: absolute;
      left: 48px;
      background: var(--primary-graphite);
      color: var(--text-inverse);
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 4px;
      white-space: nowrap;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.2s;
      font-family: var(--font-body);
      letter-spacing: 0;
      font-weight: 400;
    }
    .nav-icons a:hover::after {
      opacity: 1;
    }

    .bottom-icons {
      display: flex;
      flex-direction: column;
      gap: 16px;
      color: var(--text-muted);
    }

    /* 主内容区偏移 */
    .main-content {
      margin-left: 80px;
      width: calc(100% - 80px);
      background: var(--bg-warm);
    }

    /* 移动端顶部导航 */
    .mobile-nav {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: var(--primary-graphite);
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
      z-index: 1040;
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    }
    .mobile-logo {
      font-weight: 700;
      color: var(--accent-champagne);
      font-size: 1.2rem;
    }
    .mobile-menu-btn {
      background: none;
      border: none;
      color: var(--text-inverse);
      font-size: 1.8rem;
    }
    .mobile-overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(26,29,35,0.98);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      z-index: 1050;
      transform: translateX(100%);
      transition: transform 0.3s ease;
    }
    .mobile-overlay.show {
      transform: translateX(0);
    }
    .mobile-overlay a {
      color: var(--text-inverse);
      font-size: 1.5rem;
      font-weight: 500;
      letter-spacing: 0.08em;
    }

    /* 通用区块 */
    .section-block {
      padding: 120px 0;
    }
    .section-title {
      font-size: 2.8rem;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--text-primary);
    }
    .title-decor {
      width: 40px;
      height: 3px;
      background: var(--accent-champagne);
      margin: 12px 0 16px;
    }
    .subtitle {
      font-size: 1rem;
      color: var(--text-secondary);
      font-weight: 400;
      max-width: 600px;
    }

    /* Hero */
    .hero-section {
      height: 100vh;
      background: linear-gradient(135deg, #1A1D23 0%, #22262D 100%);
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: flex;
      width: 100%;
      height: 100%;
    }
    .hero-left {
      flex: 1;
      display: flex;
      flex-direction: column;
      justify-content: center;
      padding: 0 10%;
      color: var(--text-inverse);
    }
    .hero-right {
      flex: 1;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .data-panel {
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(197,168,126,0.25);
      border-radius: 16px;
      padding: 32px;
      color: white;
      width: 280px;
      font-family: var(--font-number);
    }
    .hero-h1 {
      font-size: 4.5rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 1.25rem;
      color: #ccc;
      margin-bottom: 32px;
    }
    .btn-primary-custom {
      background: var(--accent-champagne);
      color: var(--primary-graphite);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--border-radius-btn);
      border: none;
      transition: all var(--transition-smooth);
      position: relative;
      overflow: hidden;
    }
    .btn-primary-custom:hover {
      background: #B3936A;
      color: #000;
    }
    .btn-primary-custom::after {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
      transition: left 0.5s;
    }
    .btn-primary-custom:hover::after {
      left: 100%;
    }

    /* 指标卡片 */
    .metric-value {
      font-family: var(--font-number);
      font-size: 3.2rem;
      font-weight: 700;
      color: var(--text-primary);
    }

    /* 服务卡片 */
    .service-card {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--border-radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition-smooth);
      position: relative;
      height: 100%;
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .service-card::before {
      content: '';
      position: absolute;
      left: 0;
      top: 20px;
      width: 4px;
      height: 40px;
      background: var(--highlight-teal);
      opacity: 0;
      transition: opacity var(--transition-smooth);
    }
    .service-card:hover::before {
      opacity: 1;
    }
    .service-icon {
      font-size: 2.5rem;
      color: var(--highlight-teal);
      margin-bottom: 20px;
    }

    /* 对比区块 */
    .compare-left {
      background: #F0EEEA;
      border-radius: var(--border-radius-lg);
    }
    .compare-right {
      background: #FFFFFF;
      border: 1px solid var(--accent-champagne);
      border-radius: var(--border-radius-lg);
    }

    /* 流程步骤 */
    .step-circle {
      width: 56px;
      height: 56px;
      border: 2px solid var(--accent-champagne);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--highlight-teal);
      background: white;
      margin: 0 auto;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 0;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
    }

    /* 表单 */
    .form-control-custom {
      background: #22262D;
      border: none;
      border-radius: var(--border-radius-input);
      color: white;
      padding: 12px 16px;
    }
    .form-control-custom:focus {
      box-shadow: 0 0 0 3px rgba(197,168,126,0.2);
      background: #2a2e35;
    }

    footer {
      background: var(--primary-graphite);
      color: var(--text-muted);
    }

    @media (max-width: 992px) {
      .side-nav {
        display: none;
      }
      .mobile-nav {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        padding-top: 64px;
      }
      .hero-h1 {
        font-size: 2.8rem;
      }
      .hero-grid {
        flex-direction: column;
      }
      .hero-right {
        min-height: 300px;
      }
      .section-block {
        padding: 80px 0;
      }
    }