/* roulang page: index */
:root {
      --primary: #FF5A1F;
      --primary-dark: #E04D12;
      --secondary: #0F172A;
      --accent: #F59E0B;
      --bg-light: #F8FAFC;
      --white: #FFFFFF;
      --gray-50: #F9FAFB;
      --gray-100: #F1F5F9;
      --gray-200: #E2E8F0;
      --gray-300: #CBD5E1;
      --gray-400: #94A3B8;
      --gray-500: #64748B;
      --gray-600: #475569;
      --gray-700: #334155;
      --gray-800: #1E293B;
      --fs-base: 16px;
      --fw-normal: 400;
      --fw-medium: 500;
      --fw-bold: 700;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.12);
      --shadow-lg: 0 16px 40px rgba(0,0,0,0.12);
      --container-max: 1200px;
      --nav-height: 72px;
      --transition-fast: 0.2s ease;
      --transition-smooth: 0.25s ease;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', system-ui, -apple-system, sans-serif;
      font-size: var(--fs-base);
      font-weight: var(--fw-normal);
      line-height: 1.75;
      color: #1E293B;
      background-color: var(--bg-light);
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-fast);
    }

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

    button, input {
      font-family: inherit;
    }

    /* 导航栏 */
    .nav-bar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: var(--nav-height);
      display: flex;
      align-items: center;
      background: transparent;
      backdrop-filter: blur(12px);
      transition: background var(--transition-smooth), box-shadow var(--transition-smooth);
      will-change: background;
    }

    .nav-bar.scrolled {
      background: rgba(15, 23, 42, 0.95);
      box-shadow: 0 4px 24px rgba(0, 0, 0, 0.2);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }

    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: white;
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.5px;
      text-shadow: 0 2px 8px rgba(0,0,0,0.25);
    }

    .logo svg {
      width: 36px;
      height: 36px;
      fill: none;
      stroke: var(--primary);
      stroke-width: 2.5;
    }

    .nav-links {
      display: flex;
      gap: 36px;
      list-style: none;
    }

    .nav-links a {
      color: white;
      font-weight: 500;
      font-size: 0.95rem;
      transition: color var(--transition-fast), border-bottom var(--transition-fast);
      border-bottom: 2px solid transparent;
      padding-bottom: 4px;
    }

    .nav-links a:hover {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    /* 移动端菜单 */
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      z-index: 1100;
      background: transparent;
      border: none;
      padding: 8px;
    }

    .hamburger span {
      display: block;
      width: 28px;
      height: 2.5px;
      background: white;
      border-radius: 4px;
      transition: var(--transition-smooth);
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--secondary);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
      transform: translateY(-100%);
      opacity: 0;
      transition: transform 0.4s cubic-bezier(0.2, 0.9, 0.3, 1), opacity 0.3s ease;
      z-index: 1050;
      list-style: none;
      backdrop-filter: blur(20px);
    }

    .mobile-menu.active {
      transform: translateY(0);
      opacity: 1;
    }

    .mobile-menu a {
      font-size: 2rem;
      font-weight: 600;
      color: white;
      letter-spacing: 1px;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      background-color: var(--secondary);
      background-image: repeating-linear-gradient(45deg, rgba(255,90,31,0.08) 0px, rgba(255,90,31,0.08) 2px, transparent 2px, transparent 12px);
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding: 0 20px;
    }

    .hero-content {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      z-index: 2;
    }

    .hero-left h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      color: white;
      margin-bottom: 24px;
    }

    .hero-left h1 span {
      color: var(--primary);
    }

    .hero-desc {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 36px;
      max-width: 460px;
      line-height: 1.7;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 34px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      border: none;
      transition: background var(--transition-fast), transform var(--transition-fast);
      display: inline-block;
      text-align: center;
    }

    .btn-primary:hover {
      background: #E04D12;
      transform: translateY(-2px);
      box-shadow: var(--shadow-md);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: white;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      transition: background var(--transition-fast), border-color var(--transition-fast);
      display: inline-flex;
      align-items: center;
    }

    .btn-outline:hover {
      background: rgba(255,90,31,0.2);
      border-color: white;
      color: white;
    }

    .hero-right-card {
      background: rgba(255,255,255,0.05);
      backdrop-filter: blur(16px);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      border: 1px solid rgba(255,255,255,0.1);
    }

    .score-mock {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .score-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: rgba(255,255,255,0.08);
      border-radius: 8px;
      padding: 14px 18px;
      color: white;
    }
    .score-team {
      font-weight: 600;
    }
    .score-num {
      font-family: 'DIN Alternate', 'Roboto Mono', monospace;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
    }

    /* 通用区块标题 */
    .section {
      padding: 90px 20px;
    }

    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--secondary);
    }
    .section-title .divider {
      width: 60px;
      height: 4px;
      background: var(--primary);
      margin: 16px auto 0;
      border-radius: 2px;
    }

    /* 功能卡片grid */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
    }
    .feature-card {
      background: white;
      padding: 36px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition-smooth);
      text-align: center;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .feature-icon {
      width: 56px;
      height: 56px;
      margin: 0 auto 20px;
      stroke: var(--primary);
      fill: none;
    }
    .feature-card h3 {
      font-size: 1.35rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .feature-card p {
      color: #475569;
      line-height: 1.65;
    }

    /* 数据深色区 */
    .dark-bg-section {
      background: var(--secondary);
      color: white;
      padding: 80px 20px;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 48px;
      text-align: center;
    }
    .stat-number {
      font-family: 'DIN Alternate', 'Roboto Mono', monospace;
      font-size: 3.5rem;
      font-weight: 700;
      background: linear-gradient(135deg, #FF5A1F, #F59E0B);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .stat-label {
      color: #CBD5E1;
      margin-top: 12px;
      font-size: 1.1rem;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: transform var(--transition-smooth);
    }
    .case-card:hover {
      transform: translateY(-8px);
    }
    .case-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .case-text {
      padding: 24px;
    }
    .case-text h3 {
      font-weight: 700;
      margin-bottom: 8px;
    }
    .case-quote {
      font-style: italic;
      color: #475569;
    }

    /* 解决方案交替 */
    .solution-alt {
      display: flex;
      align-items: center;
      gap: 65px;
      margin-bottom: 70px;
      flex-wrap: wrap;
    }
    .solution-alt.reverse {
      flex-direction: row-reverse;
    }
    .sol-text, .sol-img {
      flex: 1;
      min-width: 280px;
    }
    .sol-img img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-md);
    }

    /* FAQ */
    .faq-wrapper {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--gray-200);
      padding: 0;
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      padding: 20px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.15rem;
      cursor: pointer;
      text-align: left;
      color: #0F172A;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: #475569;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 16px;
    }
    .arrow-icon {
      transition: transform 0.3s;
    }
    .faq-item.active .arrow-icon {
      transform: rotate(180deg);
    }

    /* CTA横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #FF5A1F, #E04D12);
      padding: 80px 20px;
      text-align: center;
      color: white;
    }
    .cta-title {
      font-size: 2.5rem;
      font-weight: 700;
    }
    .btn-white {
      background: white;
      color: #FF5A1F;
      margin-top: 28px;
      padding: 16px 48px;
      font-weight: 700;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      box-shadow: 0 10px 20px rgba(0,0,0,0.15);
      animation: pulse 2s infinite;
    }
    @keyframes pulse {
      0% { transform: scale(1); }
      50% { transform: scale(1.05); }
      100% { transform: scale(1); }
    }

    /* Footer */
    .footer {
      background: #1E293B;
      color: #CBD5E1;
      padding: 60px 20px 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      color: white;
      margin-bottom: 16px;
    }
    .footer-col a {
      display: block;
      color: #94A3B8;
      margin-bottom: 12px;
    }
    .footer-bottom {
      border-top: 1px solid #334155;
      padding-top: 20px;
      text-align: center;
      color: #64748B;
    }

    @media (max-width: 1024px) {
      .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-left h1 { font-size: 2.8rem; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .features-grid { grid-template-columns: 1fr 1fr; }
      .cases-grid, .stats-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero-left h1 { font-size: 2.2rem; }
    }