/* roulang page: index */
:root {
      --red: #E63946;
      --red-dark: #C1121F;
      --black-deep: #0B0C10;
      --cyan-data: #00F5D4;
      --bg-warm: #F8F9FA;
      --white: #FFFFFF;
      --text-heading: #1A1A2E;
      --text-body: #4A4A5A;
      --text-weak: #7B7B8B;
      --text-on-dark: #F0F0F0;
      --border-card: #E9ECEF;
      --border-input: #D1D5DB;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 10px 25px rgba(0,0,0,0.08), 0 4px 10px rgba(0,0,0,0.04);
      --font-sans: 'PingFang SC', 'Noto Sans SC', 'Microsoft YaHei', 'Inter', sans-serif;
      --font-mono: 'Inter', 'SF Mono', 'Roboto Mono', monospace;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      color: var(--text-heading);
    }
    h1 {
      font-size: clamp(2.5rem, 5vw, 4.5rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      line-height: 1.1;
    }
    h2 {
      font-size: clamp(2rem, 3.5vw, 3rem);
      font-weight: 700;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    h2::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 40px;
      height: 3px;
      background-color: var(--red);
      border-radius: 2px;
    }
    h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .text-mono {
      font-family: var(--font-mono);
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s ease, backdrop-filter 0.3s ease;
      background: transparent;
      backdrop-filter: blur(0px);
    }
    .site-header.scrolled {
      background: rgba(11,12,16,0.92);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--white);
      letter-spacing: -0.5px;
      white-space: nowrap;
      transition: color 0.3s;
    }
    .scrolled .logo {
      color: var(--text-on-dark);
    }
    .nav-links {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--white);
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    .scrolled .nav-links a {
      color: #ccc;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--white);
    }
    .scrolled .nav-links a:hover,
    .scrolled .nav-links a.active {
      color: var(--white);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background-color: var(--cyan-data);
      transition: width 0.3s ease;
    }
    .nav-links a.active::after,
    .nav-links a:hover::after {
      width: 20px;
    }
    .btn-primary {
      background: var(--red);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      transition: background 0.25s ease, box-shadow 0.25s ease;
      white-space: nowrap;
    }
    .btn-primary:hover {
      background: var(--red-dark);
      box-shadow: 0 0 20px rgba(230,57,70,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--red);
      color: var(--red);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s ease;
      white-space: nowrap;
    }
    .btn-outline:hover {
      background: var(--red);
      color: white;
    }
    .btn-ghost {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.5);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s ease;
    }
    .btn-ghost:hover {
      border-color: white;
      background: rgba(255,255,255,0.1);
    }
    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
    }
    /* Hero */
    .hero {
      background-color: var(--black-deep);
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      background-image: radial-gradient(circle at 20% 30%, rgba(0,245,212,0.08) 0%, transparent 50%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      width: 100%;
    }
    .hero-left {
      color: white;
    }
    .hero-left h1 {
      color: white;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: #ccc;
      margin-bottom: 32px;
      line-height: 1.6;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-right {
      position: relative;
      display: flex;
      justify-content: center;
      align-items: center;
    }
    .hero-visual {
      background: rgba(255,255,255,0.03);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: 16px;
      padding: 20px;
      backdrop-filter: blur(10px);
      width: 100%;
      max-width: 480px;
    }
    .hero-visual img {
      border-radius: 8px;
      width: 100%;
    }
    .live-score {
      font-family: var(--font-mono);
      color: var(--cyan-data);
      font-size: 2rem;
      font-weight: 700;
      text-align: center;
      margin-top: 16px;
      animation: blink 3s infinite;
    }
    @keyframes blink {
      0%, 100% { opacity: 1; }
      50% { opacity: 0.5; }
    }
    /* 板块通用 */
    .section {
      padding: 120px 0;
    }
    .section-dark {
      background: var(--black-deep);
      color: var(--text-on-dark);
    }
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      color: var(--text-heading);
    }
    .section-dark .section-title h2 {
      color: white;
    }
    .section-dark .section-title h2::after {
      background: var(--cyan-data);
    }
    /* 痛点卡片非对称 */
    .pain-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 24px;
    }
    .card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-card);
      transition: var(--transition-smooth);
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
      border-color: var(--cyan-data);
    }
    .card h3 {
      margin-top: 12px;
    }
    .icon-placeholder {
      font-size: 40px;
      color: var(--cyan-data);
    }
    /* 功能矩阵 */
    .feature-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      text-align: center;
    }
    /* 成果区 */
    .result-grid {
      display: grid;
      grid-template-columns: 3fr 2fr;
      gap: 60px;
      align-items: center;
    }
    .highlight-number {
      font-family: var(--font-mono);
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--cyan-data);
    }
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: 3fr 2fr;
      gap: 40px;
    }
    .quote-big {
      font-size: 1.6rem;
      font-weight: 500;
      font-style: italic;
      border-left: 4px solid var(--red);
      padding-left: 24px;
      color: var(--text-heading);
    }
    .small-testimonial {
      background: #F1F3F5;
      padding: 20px;
      border-radius: var(--radius-card);
    }
    /* FAQ */
    .faq-list {
      max-width: 720px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--white);
      border: 1px solid var(--border-card);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      background: white;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s ease;
      background: #FAFBFC;
      padding: 0 24px;
    }
    .faq-item.open .faq-answer {
      max-height: 300px;
      padding: 24px;
    }
    .faq-icon {
      transition: transform 0.3s;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
      color: var(--red);
    }
    /* CTA */
    .cta-section {
      background: var(--black-deep);
      text-align: center;
      padding: 100px 0;
    }
    /* 页脚 */
    .footer {
      background: var(--black-deep);
      color: #B0B0C0;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .copyright {
      background: #06070A;
      text-align: center;
      padding: 16px;
      font-size: 12px;
      margin-top: 40px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid, .result-grid, .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .pain-grid {
        grid-template-columns: 1fr 1fr;
      }
      .feature-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 0;
        left: 0;
        width: 100%;
        height: 56px;
        background: white;
        box-shadow: 0 -2px 10px rgba(0,0,0,0.05);
        justify-content: space-around;
        align-items: center;
        z-index: 999;
      }
      .mobile-bottom-nav a {
        font-size: 12px;
        color: #666;
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 4px;
      }
      .pain-grid, .feature-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .section {
        padding: 80px 0;
      }
    }