/* roulang page: index */
:root {
      --primary-green: #0A8F3C;
      --primary-green-hover: #07732F;
      --accent-gold: #D4A843;
      --accent-gold-hover: #B68B2E;
      --dark-bg: #1A1D20;
      --soft-bg: #F7F6F2;
      --text-main: #1E1E1E;
      --text-secondary: #5C5C5C;
      --text-on-dark: #FFFFFF;
      --success-green: #10B981;
      --warning: #F59E0B;
      --border-light: #E8E6E0;
      --card-bg: #FFFFFF;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(10,143,60,0.12);
      --shadow-lg: 0 16px 40px rgba(0,0,0,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-heading: "PingFang SC","Microsoft YaHei","Noto Sans SC","Inter",sans-serif;
      --font-body: "PingFang SC","Hiragino Sans GB","Microsoft YaHei","Inter",sans-serif;
      --container-max: 1280px;
      --nav-height: 72px;
      --section-gap: 100px;
    }

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

    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--soft-bg);
      line-height: 1.8;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    h1, h2, h3, h4, h5, h6 {
      font-family: var(--font-heading);
      font-weight: 700;
      letter-spacing: -0.015em;
    }

    h1 { font-size: clamp(36px, 5vw, 48px); }
    h2 { font-size: clamp(28px, 4vw, 36px); }
    h3 { font-size: clamp(20px, 2.5vw, 24px); font-weight: 600; }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s ease;
    }

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-heading);
      font-weight: 600;
      border: none;
      outline: none;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      border-radius: var(--radius-btn);
      white-space: nowrap;
    }

    .container {
      max-width: var(--container-max);
      margin-left: auto;
      margin-right: auto;
      padding-left: 20px;
      padding-right: 20px;
      width: 100%;
    }

    section {
      padding-top: var(--section-gap);
      padding-bottom: var(--section-gap);
    }

    /* Header & Navigation */
    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(0,0,0,0.05);
      height: var(--nav-height);
      display: flex;
      align-items: center;
      transition: background 0.3s;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 22px;
      color: var(--primary-green);
      display: flex;
      flex-direction: column;
      letter-spacing: 0.5px;
    }
    .logo .brand {
      display: flex;
      align-items: baseline;
      gap: 4px;
    }
    .logo .slogan {
      font-size: 10px;
      font-weight: 400;
      color: var(--text-secondary);
      line-height: 1.2;
      letter-spacing: 0.2px;
      margin-top: -2px;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-menu a {
      font-weight: 500;
      color: var(--text-main);
      position: relative;
      padding: 4px 0;
      font-size: 16px;
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-green);
      transition: width 0.25s ease;
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .nav-cta {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .btn-primary {
      background: var(--primary-green);
      color: white;
      padding: 12px 28px;
      box-shadow: 0 4px 12px rgba(10,143,60,0.3);
      font-size: 15px;
      border-radius: 30px;
    }
    .btn-primary:hover {
      background: var(--primary-green-hover);
      box-shadow: 0 6px 18px rgba(10,143,60,0.4);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent-gold);
      color: var(--accent-gold);
      padding: 10px 24px;
      font-size: 15px;
      border-radius: 30px;
    }
    .btn-outline:hover {
      background: rgba(212,168,67,0.08);
      border-color: var(--accent-gold-hover);
      color: var(--accent-gold-hover);
    }

    .hamburger {
      display: none;
      background: transparent;
      border: none;
      font-size: 26px;
      color: var(--text-main);
      padding: 8px;
    }

    /* Hero */
    .hero {
      padding-top: calc(var(--nav-height) + 60px);
      padding-bottom: 80px;
      background-color: var(--dark-bg);
      background-image: linear-gradient(135deg, #1A1D20 0%, #0A3A1A 100%), url('/assets/images/backpic/back-1.webp');
      background-blend-mode: overlay;
      background-size: cover;
      background-position: center;
      color: var(--text-on-dark);
      position: relative;
    }
    .hero .container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      align-items: center;
      gap: 48px;
    }
    .hero-content h1 {
      font-size: clamp(38px, 5.5vw, 52px);
      line-height: 1.2;
      margin-bottom: 20px;
      color: white;
      text-shadow: 0 4px 12px rgba(0,0,0,0.3);
    }
    .hero-content .subtitle {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
      max-width: 480px;
      line-height: 1.6;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 28px;
    }
    .hero-trust {
      display: flex;
      gap: 16px;
      color: rgba(255,255,255,0.7);
      font-size: 14px;
      align-items: center;
    }
    .hero-visual {
      display: flex;
      justify-content: center;
      align-items: center;
    }
    .mockup-frame {
      background: rgba(255,255,255,0.1);
      border: 2px solid rgba(255,255,255,0.2);
      border-radius: 28px;
      padding: 12px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      backdrop-filter: blur(8px);
    }
    .mockup-frame img {
      border-radius: 18px;
      max-width: 280px;
    }

    /* Features */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--card-bg);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: all 0.3s ease;
    }
    .feature-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-md);
      border-color: var(--primary-green);
    }
    .feature-icon {
      width: 70px;
      height: 70px;
      margin: 0 auto 20px;
      background: rgba(10,143,60,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary-green);
      font-size: 32px;
      border: 2px dashed var(--accent-gold);
    }
    .feature-card h3 {
      margin-bottom: 12px;
    }
    .feature-card p {
      color: var(--text-secondary);
      line-height: 1.7;
    }

    /* Stats */
    .stats-section {
      background: #FFFFFF;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
      gap: 20px;
    }
    .stat-item {
      padding: 20px;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--accent-gold);
      font-family: var(--font-heading);
      line-height: 1.2;
    }
    .stat-label {
      color: var(--text-secondary);
      margin-top: 8px;
      font-size: 15px;
    }
    .stat-divider {
      width: 1px;
      background: #E8E6E0;
      height: 60px;
      margin: auto 0;
    }

    /* Cases */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-light);
      transition: 0.3s;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      aspect-ratio: 16 / 9;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: 0.3s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.04);
    }
    .case-info {
      padding: 20px 24px;
    }
    .case-info h3 {
      margin-bottom: 8px;
    }

    /* Process */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      flex-wrap: wrap;
    }
    .step-item {
      flex: 1;
      text-align: center;
      position: relative;
      padding: 0 12px;
    }
    .step-circle {
      width: 56px;
      height: 56px;
      background: var(--primary-green);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
      font-weight: 700;
      margin: 0 auto 16px;
      position: relative;
      z-index: 2;
    }
    .step-line {
      position: absolute;
      top: 28px;
      left: 50%;
      width: 100%;
      height: 2px;
      border-top: 2px dashed var(--accent-gold);
      z-index: 1;
    }

    /* FAQ */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-item {
      background: white;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: white;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #F9F8F6;
      padding: 0 24px;
    }
    .faq-item.open .faq-answer {
      max-height: 300px;
      padding: 16px 24px;
    }
    .faq-icon {
      color: var(--primary-green);
      font-weight: bold;
      font-size: 20px;
    }

    /* CTA banner */
    .cta-banner {
      background: linear-gradient(135deg, #0A8F3C, #065A26);
      color: white;
      text-align: center;
      border-radius: 24px;
      padding: 64px 20px;
    }
    .cta-banner h2 {
      color: white;
      margin-bottom: 12px;
    }
    .btn-light {
      background: white;
      color: var(--primary-green);
      padding: 16px 48px;
      font-size: 18px;
      margin-top: 24px;
    }
    .btn-light:hover {
      background: #f0f0f0;
    }

    /* Footer */
    footer {
      background: var(--dark-bg);
      color: rgba(255,255,255,0.8);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
    }

    @media (max-width: 1023px) {
      .hero .container { grid-template-columns: 1fr; text-align: center; }
      .hero-visual { order: -1; }
      .features-grid, .cases-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .process-steps { flex-direction: column; gap: 32px; }
      .step-line { display: none; }
    }
    @media (max-width: 767px) {
      .nav-menu, .nav-cta .btn-outline { display: none; }
      .hamburger { display: block; }
      .mobile-menu {
        display: flex;
        flex-direction: column;
        position: fixed;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: white;
        padding: 24px;
        gap: 20px;
        transform: translateY(-120%);
        transition: 0.3s;
      }
      .mobile-menu.open { transform: translateY(0); }
      .features-grid, .cases-grid, .stats-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }