/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary-lime: #C2FF00;
      --primary-lime-hover: #A8DB00;
      --secondary-charcoal: #1E1E1E;
      --warm-sand: #F5F0E8;
      --accent-orange: #FF5C35;
      --accent-orange-hover: #E04A2A;
      --text-title: #1E1E1E;
      --text-body: #4A4A4A;
      --text-muted: #7A7A7A;
      --white: #FFFFFF;
      --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
      --card-shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.08);
      --radius-card: 16px;
      --radius-btn: 40px;
      --radius-tag: 20px;
      --transition-smooth: all 0.3s ease;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-mono: 'SF Mono', 'Cascadia Code', 'Consolas', monospace;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--warm-sand);
      color: var(--text-body);
      line-height: 1.8;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }

    /* 容器与排版 */
    .container-custom {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      color: var(--text-title);
      line-height: 1.2;
      letter-spacing: -0.02em;
    }

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

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

    /* 品牌导航 - 品牌行 */
    .brand-row {
      background-color: var(--white);
      border-bottom: 1px solid rgba(0,0,0,0.04);
      height: 70px;
      display: flex;
      align-items: center;
      position: sticky;
      top: 0;
      z-index: 50;
    }

    .logo-text {
      font-weight: 800;
      font-size: 1.8rem;
      color: var(--secondary-charcoal);
      letter-spacing: -0.5px;
    }
    .logo-text span {
      color: #C2FF00;
      background: var(--secondary-charcoal);
      padding: 0.1rem 0.6rem;
      border-radius: 8px;
      margin-left: 2px;
    }

    .nav-links a {
      font-weight: 600;
      color: var(--text-title);
      margin-left: 2rem;
      position: relative;
      padding-bottom: 4px;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: #A8DB00;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background-color: var(--primary-lime);
      transition: width 0.2s ease;
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    /* 频道行 */
    .channel-row {
      background-color: var(--warm-sand);
      border-bottom: 1px solid rgba(0,0,0,0.03);
      height: 44px;
      display: flex;
      align-items: center;
      overflow-x: auto;
      white-space: nowrap;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }
    .channel-row::-webkit-scrollbar {
      display: none;
    }
    .channel-tag {
      display: inline-block;
      padding: 0.4rem 1.2rem;
      border-radius: var(--radius-tag);
      font-weight: 600;
      font-size: 0.9rem;
      color: var(--text-title);
      background: transparent;
      transition: var(--transition-smooth);
      cursor: default;
      margin-right: 0.5rem;
    }
    .channel-tag:hover {
      background-color: var(--primary-lime);
      color: var(--secondary-charcoal);
    }

    /* 按钮体系 */
    .btn-primary {
      background-color: var(--primary-lime);
      color: var(--secondary-charcoal);
      font-weight: 700;
      padding: 0.8rem 2.2rem;
      border-radius: var(--radius-btn);
      display: inline-block;
      transition: var(--transition-smooth);
      border: none;
      cursor: pointer;
      text-align: center;
    }
    .btn-primary:hover {
      background-color: var(--primary-lime-hover);
      transform: scale(1.03);
      box-shadow: 0 6px 18px rgba(194,255,0,0.25);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--secondary-charcoal);
      color: var(--secondary-charcoal);
      font-weight: 700;
      padding: 0.75rem 2.1rem;
      border-radius: var(--radius-btn);
      display: inline-block;
      transition: var(--transition-smooth);
      cursor: pointer;
    }
    .btn-outline:hover {
      background-color: var(--secondary-charcoal);
      color: var(--primary-lime);
      border-color: var(--secondary-charcoal);
    }

    .btn-accent {
      background-color: var(--accent-orange);
      color: white;
      font-weight: 700;
      padding: 0.9rem 2.4rem;
      border-radius: var(--radius-btn);
      border: none;
      transition: var(--transition-smooth);
      cursor: pointer;
      display: inline-block;
    }
    .btn-accent:hover {
      background-color: var(--accent-orange-hover);
      transform: scale(1.03);
    }

    /* 卡片 */
    .card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--card-shadow);
      transition: var(--transition-smooth);
      height: 100%;
    }
    .card:hover {
      box-shadow: var(--card-shadow-hover);
      transform: translateY(-4px);
    }

    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid #E0DCD5;
    }
    .faq-question {
      background: var(--secondary-charcoal);
      color: white;
      padding: 1.2rem 1.5rem;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #2C2C2C;
    }
    .faq-answer {
      background: var(--warm-sand);
      padding: 0 1.5rem;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s ease;
    }
    .faq-item.open .faq-answer {
      max-height: 300px;
      padding: 1.5rem;
    }

    /* 统计数字 */
    .stat-number {
      font-family: var(--font-mono);
      font-weight: 700;
      color: var(--accent-orange);
    }

    /* 背景图区块 */
    .hero-bg-visual {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }

    @media (max-width: 768px) {
      .brand-row {
        height: 64px;
      }
      .nav-links {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
      .channel-row {
        height: 48px;
      }
      h1 {
        font-size: 2.2rem !important;
      }
    }
    .mobile-menu-btn {
      display: none;
    }