/* roulang page: index */
/* ----- RESET & BASE ----- */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    :root {
      --deep-purple: #1A0A2E;
      --champagne-gold: #C9A84C;
      --champagne-dark: #B8993A;
      --bg-warm: #F9F6F0;
      --card-white: #FFFFFF;
      --dark-section: #0D0618;
      --text-primary: #1E1E1E;
      --text-secondary: #4A4A4A;
      --text-muted: #B0A8C0;
      --border-light: #E5DDD0;
      --shadow-sm: 0 4px 20px rgba(26,10,46,0.06);
      --shadow-hover: 0 8px 30px rgba(26,10,46,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --font-serif: 'Noto Serif SC', 'Source Han Serif SC', 'Times New Roman', serif;
      --font-sans: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition-base: 0.25s ease;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-primary);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-base);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.5px;
      border: none;
      background: transparent;
      transition: all var(--transition-base);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      border-radius: var(--radius-btn);
      min-height: 48px;
      padding: 0 32px;
      line-height: 1.2;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }
    h1, h2, h3 {
      font-family: var(--font-serif);
      font-weight: 700;
      line-height: 1.3;
    }
    h1 { font-size: 3rem; letter-spacing: -0.5px; }
    h2 { font-size: 2.25rem; font-weight: 600; }
    h3 { font-size: 1.375rem; font-weight: 600; }
    @media (max-width: 768px) {
      h1 { font-size: 2.2rem; }
      h2 { font-size: 1.8rem; }
      h3 { font-size: 1.2rem; }
    }
    .section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      .section {
        padding: 60px 0;
      }
    }
    .text-gold { color: var(--champagne-gold); }
    .bg-dark { background-color: var(--dark-section); }
    .border-gold { border: 1px solid var(--champagne-gold); }

    /* ----- NAVIGATION ----- */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      box-shadow: 0 1px 4px rgba(0,0,0,0.04);
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      border-bottom: 1px solid rgba(229,221,208,0.3);
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: baseline;
      gap: 4px;
    }
    .logo-main {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 1.5rem;
      background: linear-gradient(135deg, #C9A84C 0%, #B8993A 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .logo-domain {
      font-size: 0.75rem;
      color: #6B6B6B;
      margin-left: 4px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-link {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 4px 0;
      position: relative;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--champagne-gold);
      transition: width var(--transition-base);
    }
    .nav-link:hover { color: var(--champagne-gold); }
    .nav-link:hover::after { width: 100%; }
    .btn-primary {
      background: var(--champagne-gold);
      color: var(--deep-purple);
      font-weight: 600;
    }
    .btn-primary:hover { background: var(--champagne-dark); }
    .btn-outline-gold {
      border: 1px solid var(--champagne-gold);
      color: var(--champagne-gold);
      background: transparent;
    }
    .btn-outline-gold:hover {
      background: var(--champagne-gold);
      color: var(--deep-purple);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      width: 28px;
      height: 24px;
      justify-content: center;
    }
    .hamburger span {
      display: block;
      width: 100%;
      height: 2px;
      background: var(--deep-purple);
      transition: 0.3s;
    }
    .mobile-menu {
      display: none;
    }
    @media (max-width: 1023px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--deep-purple);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 32px;
        z-index: 999;
        transform: translateY(-100%);
        transition: transform 0.4s ease;
      }
      .mobile-menu.active { transform: translateY(0); }
      .mobile-menu a {
        color: var(--champagne-gold);
        font-size: 1.4rem;
        font-weight: 500;
      }
      .mobile-close {
        position: absolute;
        top: 24px;
        right: 24px;
        background: none;
        border: none;
        color: #fff;
        font-size: 2rem;
      }
    }

    /* ----- HERO ----- */
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      align-items: center;
      gap: 60px;
      min-height: 85vh;
      padding-top: 100px;
    }
    .hero-left h1 {
      font-size: 3.4rem;
      margin-bottom: 20px;
      color: var(--deep-purple);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 90%;
    }
    .hero-buttons { display: flex; gap: 16px; flex-wrap: wrap; }
    .hero-right {
      position: relative;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(26,10,46,0.15);
      background: #1A0A2E;
    }
    .hero-right img {
      width: 100%;
      height: auto;
      aspect-ratio: 4/3;
      object-fit: cover;
      opacity: 0.9;
    }
    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
      }
      .hero-sub { max-width: 100%; }
      .hero-buttons { justify-content: center; }
      .hero-right { max-width: 480px; margin: 0 auto; }
    }

    /* ----- HIGHLIGHTS GRID ----- */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      margin-top: 40px;
    }
    .highlight-card {
      background: var(--card-white);
      padding: 32px 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition-base);
      border: 1px solid transparent;
    }
    .highlight-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-color: var(--champagne-gold);
    }
    .highlight-icon {
      font-size: 2.8rem;
      color: var(--champagne-gold);
      margin-bottom: 18px;
    }
    .wide-card {
      grid-column: span 2;
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .wide-card img {
      width: 140px;
      height: 140px;
      object-fit: cover;
      border-radius: 12px;
    }
    @media (max-width: 1024px) {
      .highlights-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .wide-card { grid-column: span 2; }
    }
    @media (max-width: 640px) {
      .highlights-grid {
        grid-template-columns: 1fr;
      }
      .wide-card { flex-direction: column; grid-column: span 1; }
    }

    /* ----- CASE WATERFALL ----- */
    .waterfall {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .case-card {
      background: #fff;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
    }
    .case-info {
      padding: 20px;
    }
    .case-tag {
      display: inline-block;
      background: rgba(201,168,76,0.1);
      color: var(--champagne-gold);
      font-size: 0.8rem;
      padding: 2px 12px;
      border-radius: 20px;
      margin-top: 8px;
    }
    @media (max-width: 768px) {
      .waterfall { grid-template-columns: 1fr; }
    }

    /* ----- COMPARE ----- */
    .compare-wrapper {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      gap: 0;
    }
    .compare-card {
      padding: 40px;
      border-radius: 20px;
    }
    .compare-left { background: #f1ede8; }
    .compare-right {
      background: var(--deep-purple);
      color: white;
      border: 1px solid var(--champagne-gold);
    }
    .vs-badge {
      background: var(--champagne-gold);
      color: var(--deep-purple);
      width: 50px;
      height: 50px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.2rem;
      margin: 0 -25px;
      z-index: 2;
    }
    @media (max-width: 768px) {
      .compare-wrapper {
        grid-template-columns: 1fr;
        gap: 20px;
      }
      .vs-badge { margin: 10px auto; }
    }

    /* ----- FAQ ----- */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer { max-height: 200px; margin-top: 12px; }

    /* ----- CTA BANNER ----- */
    .cta-banner {
      background: var(--dark-section);
      text-align: center;
      padding: 80px 20px;
      color: white;
    }

    /* ----- FOOTER ----- */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr 1fr;
      gap: 40px;
      color: var(--text-muted);
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }