/* roulang page: index */
:root {
      --primary-deep: #0F0F12;
      --accent-gold: #D4AF37;
      --accent-red: #E63946;
      --bg-light: #F8F9FA;
      --bg-white: #FFFFFF;
      --bg-dark: #1A1A1E;
      --text-dark: #0F0F12;
      --text-body: #4A4A55;
      --text-light: #7C7C8A;
      --border-light: #E9ECEF;
      --radius-card: 16px;
      --radius-btn: 8px;
      --shadow-card: 0 8px 24px rgba(15, 15, 18, 0.06);
      --shadow-hover: 0 16px 32px rgba(15, 15, 18, 0.12);
      --transition: all 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
    }
    h1, h2, h3, .number-font {
      font-family: 'Montserrat', 'Inter', 'Noto Sans SC', sans-serif;
      color: var(--text-dark);
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--bg-white);
      border-bottom: 1px solid var(--border-light);
      backdrop-filter: blur(8px);
      background: rgba(255,255,255,0.92);
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-weight: 900;
      font-size: 1.8rem;
      letter-spacing: -0.5px;
      color: var(--primary-deep);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo span {
      color: var(--accent-gold);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      text-decoration: none;
      font-weight: 500;
      color: var(--text-body);
      transition: var(--transition);
      font-size: 0.95rem;
      position: relative;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-gold);
    }
    .btn-primary {
      background: var(--accent-gold);
      color: var(--primary-deep);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: 50px;
      text-decoration: none;
      display: inline-block;
      transition: var(--transition);
      border: none;
      cursor: pointer;
      letter-spacing: 0.3px;
      box-shadow: 0 4px 12px rgba(212, 175, 55, 0.25);
    }
    .btn-primary:hover {
      background: #C5A028;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(212, 175, 55, 0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent-gold);
      color: var(--accent-gold);
      font-weight: 600;
      padding: 10px 26px;
      border-radius: 50px;
      text-decoration: none;
      transition: var(--transition);
    }
    .btn-outline:hover {
      background: var(--accent-gold);
      color: var(--primary-deep);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary-deep);
      cursor: pointer;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 1.2rem;
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 320px;
        height: 100vh;
        background: var(--bg-white);
        flex-direction: column;
        justify-content: center;
        gap: 2rem;
        box-shadow: -8px 0 30px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        padding: 2rem;
      }
      .nav-links.active {
        right: 0;
      }
      .menu-toggle {
        display: block;
      }
      .nav-links .btn-primary {
        width: 100%;
        text-align: center;
      }
    }
    /* Hero */
    .hero {
      display: flex;
      align-items: center;
      gap: 3rem;
      padding: 4rem 0 5rem;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: var(--shadow-hover);
    }
    .hero-right img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    .badge-group {
      display: flex;
      gap: 1rem;
      margin: 1.5rem 0 2rem;
      flex-wrap: wrap;
    }
    .badge {
      background: var(--bg-white);
      border-radius: 12px;
      padding: 8px 18px;
      font-weight: 700;
      font-size: 0.9rem;
      display: flex;
      align-items: center;
      gap: 6px;
      box-shadow: 0 4px 12px rgba(0,0,0,0.04);
    }
    .badge .num {
      color: var(--accent-red);
      font-size: 1.4rem;
      font-weight: 800;
    }
    h1 {
      font-size: clamp(2.8rem, 5vw, 3.8rem);
      font-weight: 900;
      line-height: 1.2;
      letter-spacing: -1px;
      color: var(--primary-deep);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-body);
      margin: 1.2rem 0 1.8rem;
      max-width: 480px;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    @media (max-width: 768px) {
      .hero {
        flex-direction: column;
        gap: 2rem;
      }
      .hero-right {
        order: -1;
      }
    }
    /* 通用区块标题 */
    .section-title {
      text-align: center;
      margin-bottom: 3rem;
    }
    .section-title h2 {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--primary-deep);
      display: inline-block;
      position: relative;
    }
    .section-title h2::after {
      content: '';
      position: absolute;
      bottom: -12px;
      left: 50%;
      transform: translateX(-50%);
      width: 60px;
      height: 4px;
      background: var(--accent-gold);
      border-radius: 2px;
    }
    /* 优势卡片网格 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin: 3rem 0 4rem;
    }
    .adv-card {
      background: var(--bg-white);
      padding: 2rem 1.5rem;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      text-align: center;
    }
    .adv-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .adv-icon {
      font-size: 2.4rem;
      margin-bottom: 1rem;
    }
    .adv-card h3 {
      font-size: 1.4rem;
      margin-bottom: 0.6rem;
    }
    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 产品瀑布流 */
    .waterfall {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin: 3rem 0;
    }
    .waterfall-card {
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
      background: var(--bg-white);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .waterfall-card img {
      width: 100%;
      display: block;
      aspect-ratio: 4/3;
      object-fit: cover;
    }
    .waterfall-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(transparent, rgba(15,15,18,0.7));
      padding: 1.5rem;
      color: white;
      transition: var(--transition);
    }
    .waterfall-card:hover .waterfall-overlay {
      background: linear-gradient(transparent, rgba(15,15,18,0.85));
    }
    .waterfall-card h3 {
      color: white;
      font-weight: 700;
    }
    @media (max-width: 768px) {
      .waterfall {
        grid-template-columns: 1fr;
      }
    }
    /* 对比区 */
    .compare-block {
      display: flex;
      align-items: center;
      gap: 1rem;
      margin: 4rem 0;
    }
    .compare-col {
      flex: 1;
      background: var(--bg-white);
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
    }
    .compare-col.dark {
      background: var(--primary-deep);
      color: #e0e0e0;
    }
    .compare-col h3 {
      margin-bottom: 1.5rem;
      color: var(--accent-gold);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 0.8rem;
      margin: 1rem 0;
    }
    .vs-badge {
      background: var(--accent-red);
      color: white;
      font-weight: 800;
      font-size: 1.5rem;
      padding: 0.8rem;
      border-radius: 50%;
      width: 60px;
      height: 60px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    @media (max-width: 768px) {
      .compare-block {
        flex-direction: column;
      }
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 1.2rem 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      align-items: center;
      gap: 1rem;
      font-weight: 700;
      color: var(--primary-deep);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
      padding-left: 2.2rem;
    }
    .faq-item.active .faq-answer {
      max-height: 180px;
      padding-top: 0.8rem;
    }
    /* 联系 */
    .contact-section {
      background: var(--bg-dark);
      border-radius: 32px;
      padding: 4rem 2rem;
      margin: 4rem 0;
      color: white;
    }
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
      margin-top: 2rem;
    }
    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 14px;
      border-radius: var(--radius-btn);
      border: 1px solid rgba(255,255,255,0.2);
      background: rgba(255,255,255,0.08);
      color: white;
      margin-bottom: 1rem;
    }
    .contact-form input:focus, .contact-form textarea:focus {
      border-color: var(--accent-gold);
      box-shadow: 0 0 0 3px rgba(212,175,55,0.3);
      outline: none;
    }
    @media (max-width: 768px) {
      .contact-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 页脚 */
    .footer {
      background: var(--primary-deep);
      color: #aaa;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    .footer a {
      color: #ccc;
      text-decoration: none;
      display: block;
      margin: 0.4rem 0;
    }
    .footer a:hover {
      color: var(--accent-gold);
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }