/* roulang page: index */
:root {
      --primary: #E43D2A;
      --primary-dark: #C5301F;
      --secondary-dark: #1A1A2E;
      --accent-gold: #F5A623;
      --bg-light: #F9FAFB;
      --bg-white: #FFFFFF;
      --text-main: #1F2937;
      --text-muted: #6B7280;
      --text-on-dark: #FFFFFF;
      --success: #10B981;
      --warning: #EF4444;
      --border-light: #E5E7EB;
      --radius-lg: 12px;
      --radius-md: 8px;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.12);
      --font-title: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-body: 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', sans-serif;
      --font-mono: 'DIN Alternate', 'Roboto Mono', 'Noto Sans SC', monospace;
      --max-width: 1280px;
      --nav-height: 72px;
      --nav-height-mobile: 60px;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--nav-height);
    }

    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--bg-white);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      background: none;
      transition: all 0.3s ease;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航系统 */
    #main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: transparent;
      z-index: 1000;
      display: flex;
      align-items: center;
      transition: background 0.3s ease, box-shadow 0.3s ease, height 0.3s ease;
    }

    #main-nav.scrolled {
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(10px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-title);
      font-weight: 800;
      font-size: 1.6rem;
      color: #fff;
      letter-spacing: -0.02em;
      transition: color 0.3s ease;
    }

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

    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm-1 15l-4-4 1.41-1.41L11 14.17l5.59-5.59L18 10l-7 7z"/></svg>') no-repeat center;
      mask-size: contain;
      background: var(--primary);
      display: inline-block;
    }

    .scrolled .logo-icon {
      background: var(--primary);
    }

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

    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
    }

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

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .btn-nav {
      background: var(--primary);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 0.9rem;
      border: none;
      white-space: nowrap;
    }

    .btn-nav:hover {
      background: var(--primary-dark);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      padding: 8px;
      background: transparent;
      border: none;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: #fff;
      transition: 0.3s;
    }

    .scrolled .hamburger span {
      background: var(--text-main);
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: white;
      box-shadow: -5px 0 25px rgba(0,0,0,0.15);
      z-index: 1100;
      padding: 80px 32px 32px;
      display: flex;
      flex-direction: column;
      gap: 24px;
      transition: right 0.35s ease;
      list-style: none;
    }

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

    .mobile-menu a {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--text-main);
      border-bottom: 1px solid var(--border-light);
      padding-bottom: 12px;
    }

    .mobile-menu .btn-nav {
      text-align: center;
      margin-top: 16px;
    }

    .overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.5);
      z-index: 1050;
      display: none;
    }

    .overlay.show {
      display: block;
    }

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

    #hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,26,46,0.8) 0%, rgba(228,61,42,0.45) 100%);
    }

    .hero-content {
      position: relative;
      max-width: 800px;
      padding: 0 24px;
    }

    .hero-content h1 {
      font-family: var(--font-title);
      font-size: 3rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      text-shadow: 0 4px 15px rgba(0,0,0,0.6);
      margin-bottom: 1.25rem;
      line-height: 1.2;
    }

    .hero-sub {
      font-size: 1.2rem;
      opacity: 0.9;
      margin-bottom: 2.5rem;
      max-width: 600px;
      margin-left: auto;
      margin-right: auto;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 1rem;
      box-shadow: 0 4px 10px rgba(228,61,42,0.4);
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(228,61,42,0.5);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 1rem;
    }

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

    /* 板块通用 */
    section {
      padding: 80px 0;
    }

    .section-title {
      font-family: var(--font-title);
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 1rem;
      text-align: center;
      letter-spacing: -0.02em;
    }

    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 680px;
      margin: 0 auto 48px;
      font-size: 1.1rem;
    }

    /* 痛点区 */
    #pain-points {
      background: var(--secondary-dark);
      color: white;
    }

    .pain-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      max-width: 900px;
      margin: 0 auto;
    }

    .pain-card {
      background: #252540;
      border-left: 4px solid var(--primary);
      padding: 28px 24px;
      border-radius: var(--radius-md);
    }

    .pain-card h3 {
      font-size: 1.3rem;
      margin-bottom: 8px;
      color: white;
    }

    /* 解决方案非对称 */
    .solution-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 24px;
    }

    .solution-main {
      background: url('/assets/images/coverpic/cover-1.webp') center/cover no-repeat;
      border-radius: var(--radius-lg);
      padding: 40px 32px;
      display: flex;
      flex-direction: column;
      justify-content: flex-end;
      min-height: 320px;
      position: relative;
      color: white;
      overflow: hidden;
    }

    .solution-main::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(0deg, rgba(0,0,0,0.7) 0%, transparent 60%);
      border-radius: var(--radius-lg);
    }

    .solution-main-content {
      position: relative;
    }

    .solution-card {
      background: white;
      padding: 32px 24px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      display: flex;
      flex-direction: column;
      transition: all 0.3s ease;
    }

    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    /* 数据成果 */
    #results {
      background: var(--secondary-dark);
      color: white;
    }

    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 32px;
      text-align: center;
    }

    .stat-number {
      font-family: var(--font-mono);
      font-size: 3rem;
      font-weight: 800;
      color: var(--accent-gold);
      text-shadow: 0 0 12px rgba(245,166,35,0.5);
    }

    /* 证言轮播 */
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      scroll-snap-type: x mandatory;
      padding-bottom: 16px;
      -webkit-overflow-scrolling: touch;
      scrollbar-width: none;
    }

    .testimonial-scroll::-webkit-scrollbar {
      display: none;
    }

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

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    details {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }

    summary {
      font-weight: 600;
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
    }

    /* CTA */
    #cta {
      background: linear-gradient(135deg, #E43D2A 0%, #C5301F 100%);
      color: white;
      text-align: center;
    }

    .btn-cta-large {
      background: white;
      color: var(--primary);
      padding: 18px 48px;
      border-radius: var(--radius-lg);
      font-weight: 700;
      font-size: 1.2rem;
    }

    /* 页脚 */
    footer {
      background: var(--secondary-dark);
      color: #9CA3AF;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .solution-grid { grid-template-columns: 1fr 1fr; }
      .solution-main { grid-column: span 2; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .nav-links { display: none; }
      .hamburger { display: flex; }
    }

    @media (max-width: 640px) {
      :root { --nav-height: 60px; }
      #hero { min-height: 70vh; }
      .hero-content h1 { font-size: 2rem; }
      .pain-grid { grid-template-columns: 1fr; }
      .solution-grid { grid-template-columns: 1fr; }
      .solution-main { grid-column: span 1; }
      .testimonial-card { flex: 0 0 280px; }
      .footer-grid { grid-template-columns: 1fr; }
    }