/* roulang page: index */
:root {
      --primary-purple: #7B2FF7;
      --primary-orange: #FF5E13;
      --deep-gray: #1A1A1E;
      --pure-white: #FFFFFF;
      --warm-light: #F5F3F0;
      --text-dark: #4A4A4F;
      --text-muted: #8A8A8F;
      --purple-gradient: linear-gradient(135deg, #7B2FF7 0%, #4F1FD4 100%);
      --orange-gradient: linear-gradient(135deg, #FF5E13 0%, #D44500 100%);
      --card-shadow: 0 2px 12px rgba(0,0,0,0.04);
      --card-shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --border-radius-card: 12px;
      --border-radius-btn: 8px;
      --border-radius-input: 6px;
      --font-title: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "SF Mono", "Consolas", "Monaco", monospace;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-body);
      background-color: var(--deep-gray);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 布局容器：桌面端左侧导航 + 右侧内容 */
    .app-layout {
      display: flex;
      min-height: 100vh;
    }
    
    /* 左侧竖向导航 */
    .side-nav {
      width: 240px;
      height: 100vh;
      position: fixed;
      left: 0;
      top: 0;
      background-color: var(--deep-gray);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      padding: 32px 24px;
      z-index: 100;
      box-shadow: 1px 0 15px rgba(0,0,0,0.2);
    }
    
    .brand-area {
      display: flex;
      flex-direction: column;
      gap: 48px;
    }
    
    .logo-block {
      display: flex;
      align-items: center;
      gap: 10px;
      color: var(--pure-white);
      font-weight: 700;
      font-size: 22px;
      letter-spacing: 1px;
    }
    
    .logo-icon {
      font-size: 28px;
      color: var(--primary-purple);
      filter: drop-shadow(0 0 6px rgba(123,47,247,0.6));
    }
    
    .nav-menu {
      display: flex;
      flex-direction: column;
      gap: 32px;
    }
    
    .nav-item {
      color: rgba(255,255,255,0.6);
      text-decoration: none;
      font-weight: 500;
      font-size: 16px;
      transition: color 0.2s, border-left 0.2s;
      padding-left: 12px;
      border-left: 3px solid transparent;
      display: block;
    }
    
    .nav-item:hover,
    .nav-item.active {
      color: rgba(255,255,255,1);
      border-left-color: var(--primary-purple);
    }
    
    .nav-footer {
      color: var(--text-muted);
      font-size: 13px;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
    }
    
    /* 右侧主内容区 */
    .main-content {
      margin-left: 240px;
      width: calc(100% - 240px);
      background-color: var(--pure-white);
    }
    
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 40px;
    }
    
    section {
      padding: 100px 0;
    }
    
    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background-color: var(--deep-gray);
      align-items: center;
      justify-content: space-between;
      padding: 0 24px;
      z-index: 110;
      box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    }
    
    .mobile-logo {
      color: white;
      font-weight: 700;
      font-size: 20px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    
    .hamburger {
      color: white;
      font-size: 24px;
      background: none;
      border: none;
      cursor: pointer;
    }
    
    .mobile-menu-overlay {
      display: none;
      position: fixed;
      top: 64px;
      left: 0;
      width: 100%;
      height: calc(100vh - 64px);
      background-color: var(--deep-gray);
      flex-direction: column;
      padding: 32px 24px;
      gap: 28px;
      z-index: 105;
    }
    
    .mobile-menu-overlay .nav-item {
      font-size: 20px;
      padding-left: 8px;
    }
    
    /* 排版 */
    h1 {
      font-family: var(--font-title);
      font-weight: 800;
      font-size: 48px;
      line-height: 1.2;
    }
    h2 {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 36px;
      margin-bottom: 16px;
    }
    h3 {
      font-family: var(--font-title);
      font-weight: 600;
      font-size: 24px;
    }
    .text-mono {
      font-family: var(--font-mono);
    }
    
    .btn {
      display: inline-block;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      transition: all 0.25s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      cursor: pointer;
      text-decoration: none;
      border: 2px solid transparent;
      text-align: center;
    }
    .btn-primary {
      background: var(--primary-purple);
      color: white;
      padding: 14px 32px;
      border-color: var(--primary-purple);
    }
    .btn-primary:hover {
      background: var(--purple-gradient);
      transform: scale(1.03);
      box-shadow: 0 8px 18px rgba(123,47,247,0.3);
    }
    .btn-secondary {
      background: transparent;
      color: var(--primary-orange);
      border-color: var(--primary-orange);
      padding: 14px 32px;
    }
    .btn-secondary:hover {
      background: var(--orange-gradient);
      color: white;
      border-color: transparent;
      transform: scale(1.03);
      box-shadow: 0 8px 18px rgba(255,94,19,0.25);
    }
    .btn-large {
      padding: 20px 48px;
      font-size: 18px;
    }
    
    /* Hero 区域 */
    .hero-section {
      background: radial-gradient(circle at 30% 40%, #2a2a35, #0f0f13);
      color: white;
      display: flex;
      align-items: center;
      min-height: 100vh;
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 40px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-visual {
      flex: 1;
      position: relative;
      height: 500px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      overflow: hidden;
    }
    .hero-visual::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(123,47,247,0.55), rgba(26,26,30,0.7));
    }
    .hero-text h1 {
      color: white;
      margin-bottom: 16px;
    }
    .hero-sub {
      color: rgba(255,255,255,0.8);
      max-width: 480px;
      margin-bottom: 32px;
    }
    .cta-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    /* 痛点 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 40px;
    }
    .pain-item {
      border-bottom: 1px solid #e0e0e0;
      padding-bottom: 24px;
      transition: border-color 0.3s;
    }
    .pain-item:hover {
      border-bottom-color: var(--primary-purple);
    }
    .pain-icon {
      color: var(--primary-purple);
      font-size: 28px;
      margin-bottom: 12px;
    }
    
    /* 方案非对称网格 */
    .solution-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .solution-card {
      background: white;
      border-radius: var(--border-radius-card);
      padding: 32px;
      box-shadow: var(--card-shadow);
      border-left: 4px solid var(--primary-purple);
      transition: all 0.3s ease;
      position: relative;
    }
    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-shadow-hover);
      border-left-width: 8px;
    }
    .solution-card.wide {
      grid-column: span 2;
      display: flex;
      gap: 30px;
      align-items: center;
    }
    .solution-img {
      width: 180px;
      height: 120px;
      object-fit: cover;
      border-radius: 8px;
    }
    
    /* 数据 */
    .stats-row {
      display: flex;
      justify-content: space-around;
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      font-family: var(--font-mono);
      background: linear-gradient(135deg, #7B2FF7, #4F1FD4);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .testimonial-card {
      background: var(--warm-light);
      padding: 32px;
      border-radius: var(--border-radius-card);
    }
    .quote-icon {
      color: var(--primary-orange);
      font-size: 24px;
      margin-bottom: 16px;
    }
    
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      transition: color 0.2s;
    }
    .faq-question:hover {
      color: var(--primary-purple);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-dark);
    }
    
    /* CTA 深色区 */
    .cta-dark {
      background: var(--deep-gray);
      color: white;
      text-align: center;
      padding: 100px 0;
      background-image: url('/assets/images/backpic/back-2.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
    }
    
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      color: #ccc;
    }
    .footer-brand {
      font-weight: 700;
      font-size: 20px;
      color: white;
    }
    
    @media (max-width: 1024px) {
      .side-nav { display: none; }
      .mobile-header { display: flex; }
      .main-content { margin-left: 0; width: 100%; }
      .container { padding: 0 24px; }
      h1 { font-size: 40px; }
      h2 { font-size: 30px; }
      .pain-grid { grid-template-columns: 1fr; }
      .solution-grid { grid-template-columns: 1fr; }
      .solution-card.wide { grid-column: span 1; flex-direction: column; }
      .testimonial-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
      .hero-grid { flex-direction: column; }
      .hero-visual { height: 300px; width: 100%; }
      .stats-row { flex-direction: column; gap: 30px; }
      .footer-grid { grid-template-columns: 1fr; }
    }