/* roulang page: index */
:root {
      --primary: #D9381E;
      --primary-hover: #B82E16;
      --secondary: #1A1A2E;
      --accent: #F5A623;
      --accent-hover: #E8950F;
      --bg: #F9F7F4;
      --white: #FFFFFF;
      --border: #E5E0D8;
      --text: #1A1A2E;
      --text-light: #F9F7F4;
      --text-muted: #6B6B7B;
      --font-sans: 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', sans-serif;
      --font-mono: 'DM Mono', 'Noto Sans SC', monospace;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-card: 0 2px 16px rgba(26, 26, 46, 0.06);
      --shadow-hover: 0 8px 32px rgba(217, 56, 30, 0.12);
      --transition: 0.25s ease;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --container-max: 1280px;
      --header-height: 64px;
    }

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

    body {
      font-family: var(--font-sans);
      font-size: 16px;
      line-height: 1.75;
      background-color: var(--bg);
      color: var(--text);
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 40px;
      width: 100%;
    }

    /* header / navigation */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      z-index: 1000;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 40px;
      transition: background var(--transition-smooth), box-shadow var(--transition-smooth), backdrop-filter var(--transition-smooth);
      background: transparent;
      backdrop-filter: blur(0px);
      border-bottom: 1px solid transparent;
    }

    .header.scrolled {
      background: rgba(249, 247, 244, 0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.08);
      border-bottom: 1px solid var(--border);
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: #fff;
      transition: color var(--transition-smooth);
      letter-spacing: -0.02em;
      text-decoration: none;
      z-index: 1001;
    }

    .header.scrolled .logo {
      color: var(--secondary);
    }

    .logo-icon {
      display: inline-flex;
      width: 32px;
      height: 32px;
      position: relative;
    }

    .logo-icon svg {
      width: 100%;
      height: 100%;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 0.95rem;
      transition: color var(--transition);
      letter-spacing: 0.02em;
      white-space: nowrap;
    }

    .header.scrolled .nav-links a {
      color: var(--text);
    }

    .nav-links a:hover {
      color: var(--accent);
    }

    .header-cta {
      background: var(--primary);
      color: white;
      padding: 8px 18px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background var(--transition), transform var(--transition);
      font-size: 0.9rem;
      border: none;
      cursor: pointer;
      letter-spacing: 0.03em;
    }

    .header.scrolled .header-cta {
      color: white;
    }

    .header-cta:hover {
      background: var(--primary-hover);
      transform: scale(1.02);
    }

    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 1001;
      background: none;
      border: none;
    }

    .burger span {
      width: 25px;
      height: 2px;
      background: #fff;
      transition: var(--transition-smooth);
    }

    .header.scrolled .burger span {
      background: var(--secondary);
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 75%;
      max-width: 320px;
      height: 100vh;
      background: var(--secondary);
      backdrop-filter: blur(20px);
      padding: 100px 30px 40px;
      display: flex;
      flex-direction: column;
      gap: 32px;
      transition: right 0.4s ease;
      z-index: 1000;
    }

    .mobile-menu.active {
      right: 0;
    }

    .mobile-menu a {
      color: white;
      font-size: 1.2rem;
      font-weight: 500;
      border-bottom: 1px solid rgba(255,255,255,0.15);
      padding-bottom: 12px;
    }

    .mobile-menu .header-cta {
      width: fit-content;
      margin-top: 20px;
    }

    /* hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      color: white;
      padding-top: var(--header-height);
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,26,46,0.8) 0%, rgba(217,56,30,0.2) 100%);
    }

    .hero-content {
      position: relative;
      max-width: 700px;
      margin-left: 5%;
      padding: 60px 0 40px;
    }

    .hero h1 {
      font-size: clamp(2.5rem, 6vw, 3.8rem);
      font-weight: 700;
      letter-spacing: -0.02em;
      line-height: 1.2;
      margin-bottom: 24px;
    }

    .hero-subtitle {
      font-size: 1.2rem;
      opacity: 0.9;
      margin-bottom: 40px;
      max-width: 520px;
    }

    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: all var(--transition-smooth);
      cursor: pointer;
      border: none;
      letter-spacing: 0.04em;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
    }

    .btn-primary:hover {
      background: var(--primary-hover);
      transform: scale(1.03);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
    }

    .btn-outline:hover {
      background: white;
      color: var(--secondary);
    }

    .btn-accent {
      background: var(--accent);
      color: var(--secondary);
      font-weight: 700;
    }

    .btn-accent:hover {
      background: var(--accent-hover);
    }

    .scroll-hint {
      position: absolute;
      bottom: 40px;
      left: 50%;
      transform: translateX(-50%);
      font-size: 0.9rem;
      animation: float 2s infinite;
      color: rgba(255,255,255,0.8);
    }

    @keyframes float {
      0% { transform: translateX(-50%) translateY(0); }
      50% { transform: translateX(-50%) translateY(6px); }
      100% { transform: translateX(-50%) translateY(0); }
    }

    /* sections */
    section {
      padding: 100px 0;
    }

    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      letter-spacing: -0.02em;
      margin-bottom: 16px;
    }

    .section-subtitle {
      font-size: 1.1rem;
      color: var(--text-muted);
      max-width: 600px;
      margin-bottom: 60px;
    }

    .bg-dark {
      background: var(--secondary);
      color: white;
    }

    /* pain points */
    .pain-grid {
      display: flex;
      flex-direction: column;
      gap: 70px;
    }

    .pain-item {
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .pain-item.reverse {
      flex-direction: row-reverse;
    }

    .pain-text {
      flex: 1;
    }

    .pain-badge {
      display: inline-block;
      background: rgba(217,56,30,0.1);
      color: var(--primary);
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      margin-bottom: 12px;
    }

    .pain-image {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }

    .pain-image:hover {
      transform: scale(1.02);
    }

    /* solutions asymmetric */
    .solutions-grid {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 24px;
    }

    .small-cards {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }

    .card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
      border: 1px solid var(--border);
    }

    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }

    .card-icon {
      color: var(--accent);
      font-size: 2rem;
      margin-bottom: 16px;
    }

    .large-card {
      background: url('/assets/images/coverpic/cover-2.webp') center/cover no-repeat;
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
      display: flex;
      align-items: flex-end;
      min-height: 380px;
    }

    .large-card-overlay {
      background: linear-gradient(0deg, rgba(26,26,46,0.85) 30%, transparent 100%);
      padding: 40px;
      color: white;
      width: 100%;
    }

    /* stats */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 40px;
      text-align: center;
    }

    .stat-number {
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--accent);
      font-family: var(--font-mono);
    }

    /* testimonials horizontal */
    .testimonials-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 20px;
      scroll-snap-type: x mandatory;
    }

    .testimonial-card {
      flex: 0 0 380px;
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 28px;
      border-left: 4px solid var(--primary);
      box-shadow: var(--shadow-card);
      scroll-snap-align: start;
    }

    .testimonial-user {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 20px;
    }

    .avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: url('/assets/images/coverpic/cover-3.webp') center/cover;
    }

    /* faq */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }

    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-muted);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }

    /* cta */
    .cta-section {
      background: var(--secondary);
      background-image: radial-gradient(circle at 30% 50%, rgba(217,56,30,0.2) 0%, transparent 60%);
      text-align: center;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0;
      color: var(--text-light);
    }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .solutions-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .burger { display: flex; }
      .header { padding: 0 20px; }
      .pain-item, .pain-item.reverse { flex-direction: column; }
      .stats-grid { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .hero { min-height: 85vh; }
      .hero-content { margin-left: 0; padding: 40px 20px; }
      .footer-grid { grid-template-columns: 1fr; }
    }