/* roulang page: index */
:root {
      --color-midnight: #0B0A0A;
      --color-champagne: #C8A96E;
      --color-burgundy: #6B1D2B;
      --color-warm-stone: #E5E0D8;
      --color-matte-grey: #9C9488;
      --color-basalt: #151110;
      --color-gold-border: rgba(200,169,110,0.3);
      --color-emerald: #2D5A3D;
      --color-burgundy-dark: #4A1520;
      --font-serif: "Noto Serif SC", "Times New Roman", "宋体", serif;
      --font-sans: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-english: "Cormorant Garamond", "Playfair Display", serif;
      --font-ui: "Inter", "Helvetica Neue", sans-serif;
      --transition-slow: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
      --transition-fast: 0.2s ease-out;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
      background-color: var(--color-midnight);
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--color-midnight);
      color: var(--color-warm-stone);
      line-height: 1.8;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      overflow-x: hidden;
    }

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

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

    button, input, textarea {
      font-family: inherit;
      outline: none;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding-left: 80px;
      padding-right: 80px;
    }

    @media (max-width: 1024px) {
      .container {
        padding-left: 40px;
        padding-right: 40px;
      }
    }

    @media (max-width: 768px) {
      .container {
        padding-left: 24px;
        padding-right: 24px;
      }
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(11,10,10,0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid var(--color-gold-border);
      transition: background var(--transition-slow);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: center;
      height: 80px;
      position: relative;
      max-width: 1400px;
      margin: 0 auto;
      padding: 0 40px;
    }

    .nav-left, .nav-right {
      display: flex;
      align-items: center;
      gap: 48px;
      list-style: none;
    }

    .nav-left {
      margin-right: auto;
    }

    .nav-right {
      margin-left: auto;
    }

    .nav-logo {
      position: absolute;
      left: 50%;
      transform: translateX(-50%);
      font-family: var(--font-english);
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: 0.2em;
      color: var(--color-champagne);
      text-transform: uppercase;
      white-space: nowrap;
    }

    .nav-item {
      font-family: var(--font-ui);
      font-size: 0.875rem;
      font-weight: 500;
      letter-spacing: 0.1em;
      text-transform: uppercase;
      color: var(--color-matte-grey);
      position: relative;
      padding: 8px 0;
      transition: color var(--transition-fast);
      cursor: pointer;
    }

    .nav-item::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 1px;
      background-color: var(--color-champagne);
      transition: width 0.3s ease;
    }

    .nav-item:hover {
      color: var(--color-champagne);
    }

    .nav-item:hover::after {
      width: 100%;
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: var(--color-champagne);
      font-size: 1.8rem;
      cursor: pointer;
      z-index: 1001;
      position: absolute;
      right: 24px;
      top: 50%;
      transform: translateY(-50%);
    }

    @media (max-width: 768px) {
      .nav-left, .nav-right {
        display: none;
      }
      .menu-toggle {
        display: block;
      }
      .nav-logo {
        position: static;
        transform: none;
        margin: 0 auto;
      }
      .nav-container {
        justify-content: space-between;
        padding: 0 24px;
      }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--color-midnight);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 32px;
        z-index: 999;
        opacity: 0;
        visibility: hidden;
        transition: opacity 0.3s ease, visibility 0.3s ease;
      }
      .mobile-menu.active {
        opacity: 1;
        visibility: visible;
      }
      .mobile-menu .nav-item {
        font-size: 1.2rem;
      }
    }

    /* 首屏 Hero */
    .hero {
      height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-repeat: no-repeat;
      overflow: hidden;
    }

    .hero::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(11,10,10,0.75);
      z-index: 1;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      text-align: left;
    }

    .hero-tag {
      font-family: var(--font-english);
      font-size: 0.9rem;
      letter-spacing: 0.2em;
      text-transform: uppercase;
      color: var(--color-champagne);
      margin-bottom: 24px;
      opacity: 0.9;
    }

    .hero h1 {
      font-family: var(--font-serif);
      font-size: clamp(2.25rem, 6vw, 4.5rem);
      font-weight: 700;
      line-height: 1.1;
      letter-spacing: 0.08em;
      color: var(--color-warm-stone);
      margin-bottom: 0;
      text-shadow: 0 2px 15px rgba(0,0,0,0.6);
    }

    .scroll-indicator {
      position: absolute;
      bottom: 40px;
      left: 50%;
      transform: translateX(-50%);
      z-index: 3;
      color: var(--color-champagne);
      font-size: 2rem;
      animation: pulse 1.5s ease-in-out infinite;
      cursor: pointer;
      opacity: 0.7;
    }

    @keyframes pulse {
      0% { opacity: 0.4; transform: translateX(-50%) translateY(0); }
      50% { opacity: 1; transform: translateX(-50%) translateY(8px); }
      100% { opacity: 0.4; transform: translateX(-50%) translateY(0); }
    }

    /* 解决方案层 */
    .solution {
      padding: 140px 0;
      background-color: var(--color-midnight);
    }

    .solution-grid {
      display: flex;
      gap: 80px;
      align-items: flex-start;
    }

    .solution-left {
      flex: 0 0 55%;
    }

    .solution-right {
      flex: 0 0 40%;
      display: flex;
      flex-direction: column;
      gap: 48px;
    }

    .solution-quote {
      font-family: var(--font-serif);
      font-size: clamp(1.75rem, 4vw, 3rem);
      font-weight: 600;
      line-height: 1.2;
      color: var(--color-warm-stone);
      letter-spacing: 0.05em;
    }

    .solution-item {
      display: flex;
      gap: 24px;
      align-items: baseline;
    }

    .roman-num {
      font-family: var(--font-english);
      font-size: 1.5rem;
      color: var(--color-champagne);
      font-weight: 600;
      min-width: 30px;
    }

    .solution-text {
      font-size: 1.125rem;
      color: var(--color-matte-grey);
      line-height: 1.8;
    }

    @media (max-width: 768px) {
      .solution-grid {
        flex-direction: column;
        gap: 48px;
      }
      .solution-left, .solution-right {
        flex: auto;
      }
      .solution {
        padding: 80px 0;
      }
    }

    /* 数据背书 */
    .stats {
      background-color: var(--color-basalt);
      padding: 100px 0;
    }

    .stats-row {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
      gap: 40px;
    }

    .stat-item {
      flex: 1;
      min-width: 200px;
    }

    .stat-number {
      font-family: var(--font-serif);
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--color-champagne);
      line-height: 1;
    }

    .stat-divider {
      width: 40px;
      height: 1px;
      background: var(--color-champagne);
      margin: 16px auto;
      opacity: 0.6;
    }

    .stat-label {
      font-size: 0.9rem;
      text-transform: uppercase;
      letter-spacing: 0.05em;
      color: var(--color-matte-grey);
    }

    /* 证言 */
    .testimonials {
      padding: 140px 0;
      background: var(--color-midnight);
    }

    .testimonial-carousel {
      position: relative;
      max-width: 700px;
      margin: 0 auto;
      text-align: center;
    }

    .testimonial-slide {
      opacity: 0;
      transition: opacity 0.8s ease;
      position: absolute;
      width: 100%;
      top: 0;
      left: 0;
    }

    .testimonial-slide.active {
      opacity: 1;
      position: relative;
    }

    .testimonial-text {
      font-family: var(--font-serif);
      font-size: 1.5rem;
      font-style: italic;
      line-height: 1.6;
      color: var(--color-warm-stone);
      margin-bottom: 32px;
      position: relative;
    }

    .testimonial-text::before {
      content: '“';
      font-size: 8rem;
      color: var(--color-champagne);
      opacity: 0.15;
      position: absolute;
      top: -60px;
      left: 50%;
      transform: translateX(-50%);
      font-family: var(--font-english);
      line-height: 1;
    }

    .testimonial-author {
      font-size: 0.9rem;
      color: var(--color-matte-grey);
      letter-spacing: 0.05em;
    }

    .carousel-controls {
      display: flex;
      justify-content: center;
      gap: 40px;
      margin-top: 48px;
    }

    .carousel-btn {
      background: none;
      border: 1px solid var(--color-champagne);
      color: var(--color-champagne);
      width: 44px;
      height: 44px;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: all var(--transition-fast);
      font-size: 1.2rem;
    }

    .carousel-btn:hover {
      background: var(--color-champagne);
      color: var(--color-midnight);
    }

    /* FAQ */
    .faq {
      padding: 120px 0;
      background: var(--color-midnight);
    }

    .section-tag {
      font-family: var(--font-ui);
      font-size: 0.8rem;
      letter-spacing: 0.15em;
      color: var(--color-matte-grey);
      text-transform: uppercase;
      margin-bottom: 16px;
    }

    .faq h2 {
      font-family: var(--font-serif);
      font-size: clamp(1.75rem, 4vw, 3rem);
      margin-bottom: 64px;
      color: var(--color-warm-stone);
    }

    .faq-list {
      max-width: 720px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--color-gold-border);
      padding: 24px 0;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-size: 1.1rem;
      font-weight: 500;
      color: var(--color-warm-stone);
    }

    .faq-icon {
      font-size: 1.5rem;
      color: var(--color-champagne);
      transition: transform 0.3s ease;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease-in-out;
      color: var(--color-matte-grey);
      padding-left: 20px;
      border-left: 1px solid var(--color-champagne);
      margin-top: 0;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 16px;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    .cta {
      background: var(--color-basalt);
      padding: 120px 0;
      text-align: center;
    }

    .cta h2 {
      font-family: var(--font-serif);
      font-size: clamp(2rem, 5vw, 3.5rem);
      color: var(--color-burgundy);
      margin-bottom: 24px;
    }

    .cta-sub {
      color: var(--color-matte-grey);
      margin-bottom: 48px;
      font-size: 1.1rem;
      max-width: 500px;
      margin-left: auto;
      margin-right: auto;
    }

    .btn-primary {
      background: var(--color-burgundy);
      color: var(--color-champagne);
      border: none;
      padding: 18px 56px;
      font-size: 0.9rem;
      font-weight: 600;
      letter-spacing: 0.12em;
      text-transform: uppercase;
      cursor: pointer;
      border-radius: 0;
      transition: background 0.4s ease, color 0.4s ease, box-shadow 0.4s ease;
      display: inline-block;
      text-decoration: none;
      min-width: 280px;
    }

    .btn-primary:hover {
      background: var(--color-champagne);
      color: var(--color-midnight);
      box-shadow: 0 0 25px rgba(200,169,110,0.25);
    }

    .privacy-note {
      font-size: 0.75rem;
      color: var(--color-matte-grey);
      margin-top: 24px;
    }

    /* 页脚 */
    .site-footer {
      background: var(--color-midnight);
      border-top: 1px solid var(--color-gold-border);
      padding: 80px 0 40px;
    }

    .footer-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 48px;
      margin-bottom: 48px;
    }

    .footer-col {
      flex: 1;
      min-width: 180px;
    }

    .footer-logo {
      font-family: var(--font-english);
      font-size: 1.6rem;
      color: var(--color-champagne);
      letter-spacing: 0.2em;
      margin-bottom: 12px;
    }

    .footer-sub {
      font-size: 0.8rem;
      color: var(--color-matte-grey);
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .footer-links a {
      color: var(--color-matte-grey);
      font-size: 0.9rem;
      transition: color var(--transition-fast);
    }

    .footer-links a:hover {
      color: var(--color-champagne);
    }

    .footer-contact p {
      color: var(--color-matte-grey);
      font-size: 0.9rem;
      margin-bottom: 8px;
    }

    .copyright {
      text-align: center;
      font-size: 0.8rem;
      color: var(--color-matte-grey);
      border-top: 1px solid var(--color-gold-border);
      padding-top: 32px;
    }

    .copyright small {
      display: block;
      margin-top: 8px;
      opacity: 0.8;
    }

    @media (max-width: 768px) {
      .footer-grid {
        flex-direction: column;
        text-align: center;
      }
    }

    .reveal {
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.8s ease-out, transform 0.8s ease-out;
    }

    .reveal.visible {
      opacity: 1;
      transform: translateY(0);
    }