/* roulang page: index */
:root {
      --primary-deep: #1A1A2E;
      --accent-gold: #C9A96E;
      --accent-gold-hover: #B8944F;
      --bg-warm: #F5F0EB;
      --text-primary: #2D2D2D;
      --text-secondary: #6B6B6B;
      --border-light: #E5E0DA;
      --card-bg: #FFFFFF;
      --shadow-sm: 0 2px 16px rgba(26, 26, 46, 0.06);
      --shadow-md: 0 8px 32px rgba(26, 26, 46, 0.1);
      --shadow-gold: 0 4px 20px rgba(201, 169, 110, 0.3);
      --font-serif: 'Noto Serif SC', serif;
      --font-sans: 'Noto Sans SC', sans-serif;
      --font-mono: 'DM Mono', monospace;
      --border-radius-card: 12px;
      --border-radius-btn: 8px;
      --border-radius-img: 16px;
      --transition-base: all 0.25s ease;
      --transition-card: all 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-primary);
      margin: 0;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-weight: 500;
      letter-spacing: 0.02em;
    }

    h1 {
      font-family: var(--font-serif);
      font-weight: 700;
    }

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

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

    .container-custom {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    /* 按钮定制 */
    .btn-primary-custom {
      background-color: var(--accent-gold);
      border: 1.5px solid var(--accent-gold);
      color: white;
      font-weight: 500;
      border-radius: var(--border-radius-btn);
      padding: 0.75rem 2rem;
      font-size: 1rem;
      transition: var(--transition-base);
      display: inline-block;
      text-align: center;
    }
    .btn-primary-custom:hover {
      background-color: var(--accent-gold-hover);
      border-color: var(--accent-gold-hover);
      color: white;
      box-shadow: var(--shadow-gold);
    }

    .btn-outline-custom {
      background: transparent;
      border: 1.5px solid var(--primary-deep);
      color: var(--primary-deep);
      font-weight: 500;
      border-radius: var(--border-radius-btn);
      padding: 0.75rem 2rem;
      font-size: 1rem;
      transition: var(--transition-base);
      display: inline-block;
      text-align: center;
    }
    .btn-outline-custom:hover {
      background-color: var(--primary-deep);
      color: white;
      border-color: var(--primary-deep);
    }

    .btn-white-custom {
      background: white;
      color: var(--primary-deep);
      font-weight: 600;
      border-radius: var(--border-radius-btn);
      padding: 0.85rem 2.5rem;
      font-size: 1.1rem;
      border: none;
      transition: var(--transition-base);
    }
    .btn-white-custom:hover {
      background: #f0f0f0;
      box-shadow: 0 8px 20px rgba(0,0,0,0.15);
      color: #000;
    }

    /* 导航双层 */
    .navbar-brand-custom {
      font-family: var(--font-sans);
      font-weight: 700;
      font-size: 1.6rem;
      color: var(--primary-deep);
      letter-spacing: 2px;
    }
    .top-bar {
      background: white;
      border-bottom: 1px solid var(--border-light);
      height: 64px;
      display: flex;
      align-items: center;
    }
    .channel-tabs {
      background: var(--bg-warm);
      height: 48px;
      display: flex;
      align-items: center;
      overflow-x: auto;
      white-space: nowrap;
      scrollbar-width: none;
      -ms-overflow-style: none;
      border-bottom: 1px solid var(--border-light);
    }
    .channel-tabs::-webkit-scrollbar {
      display: none;
    }
    .pill-link {
      display: inline-block;
      padding: 0.4rem 1.3rem;
      border-radius: 50px;
      font-weight: 500;
      color: var(--primary-deep);
      margin-right: 0.25rem;
      transition: var(--transition-base);
      font-size: 0.95rem;
    }
    .pill-link.active, .pill-link:hover {
      background-color: var(--accent-gold);
      color: white;
    }

    .sticky-nav {
      position: sticky;
      top: 0;
      z-index: 1020;
      background: white;
    }

    /* Hero区域 */
    .hero-section {
      background-color: var(--bg-warm);
      background-image: radial-gradient(circle at 30% 40%, rgba(201,169,110,0.08) 0%, transparent 40%);
      padding: 3rem 0 5rem;
    }
    .hero-tag {
      font-size: 0.8rem;
      letter-spacing: 2px;
      color: var(--accent-gold);
      background: rgba(201,169,110,0.1);
      padding: 0.25rem 1rem;
      border-radius: 50px;
      display: inline-block;
      margin-bottom: 1.2rem;
      font-weight: 500;
    }
    .hero-title {
      font-size: clamp(2.2rem, 5vw, 3.8rem);
      line-height: 1.25;
      color: var(--primary-deep);
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      color: var(--text-secondary);
      font-size: 1.15rem;
      max-width: 480px;
      margin-bottom: 2rem;
    }

    /* 卡片通用 */
    .solution-card, .testimonial-card {
      background: var(--card-bg);
      border-radius: var(--border-radius-card);
      box-shadow: var(--shadow-sm);
      padding: 2rem 1.8rem;
      transition: var(--transition-card);
      border: 1px solid var(--border-light);
      height: 100%;
    }
    .solution-card:hover, .testimonial-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .icon-placeholder {
      width: 48px;
      height: 48px;
      background: rgba(26,26,46,0.04);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.5rem;
      color: var(--primary-deep);
      font-size: 1.4rem;
    }

    /* 数据深色区 */
    .stats-section {
      background-color: var(--primary-deep);
      padding: 5rem 0;
      color: white;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: clamp(2.8rem, 6vw, 4.5rem);
      font-weight: 500;
      line-height: 1.1;
      color: white;
    }
    .stat-unit {
      color: var(--accent-gold);
    }
    .stat-label {
      color: rgba(255,255,255,0.75);
      font-weight: 300;
      margin-top: 0.4rem;
    }

    /* 证言引用 */
    .testimonial-quote {
      position: relative;
      font-size: 1.1rem;
      color: var(--text-primary);
      padding-left: 2rem;
    }
    .testimonial-quote::before {
      content: "“";
      font-size: 4rem;
      color: var(--accent-gold);
      opacity: 0.25;
      position: absolute;
      left: -0.2rem;
      top: -0.8rem;
      font-family: var(--font-serif);
    }

    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: transparent;
      color: var(--accent-gold);
      box-shadow: none;
      font-weight: 500;
    }
    .accordion-button {
      font-weight: 500;
      color: var(--primary-deep);
      background: transparent;
      border-bottom: 1px solid var(--border-light);
      padding: 1.2rem 0;
      font-size: 1.1rem;
    }
    .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-light);
      background: transparent;
    }
    .accordion-button::after {
      filter: invert(50%) sepia(10%) saturate(800%) hue-rotate(8deg);
    }

    /* CTA 金色区域 */
    .cta-gold {
      background: linear-gradient(135deg, #C9A96E 0%, #D4B87A 100%);
      padding: 4.5rem 0;
      position: relative;
      overflow: hidden;
    }
    .cta-gold::before {
      content: "";
      position: absolute;
      width: 300px;
      height: 300px;
      background: rgba(255,255,255,0.08);
      border-radius: 50%;
      top: -60px;
      right: -60px;
    }

    footer {
      background: var(--primary-deep);
      color: rgba(255,255,255,0.8);
      padding: 3rem 0 2rem;
      font-size: 0.95rem;
    }
    .back-to-top {
      position: fixed;
      bottom: 25px;
      right: 25px;
      width: 44px;
      height: 44px;
      background: var(--accent-gold);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.3rem;
      box-shadow: 0 6px 18px rgba(0,0,0,0.15);
      transition: var(--transition-base);
      z-index: 99;
    }
    .back-to-top:hover {
      background: var(--accent-gold-hover);
    }

    @media (max-width: 768px) {
      .hero-section {
        text-align: center;
      }
      .hero-sub {
        margin-left: auto;
        margin-right: auto;
      }
      .channel-tabs {
        justify-content: flex-start;
      }
    }