/* roulang page: index */
:root {
      --primary-yellow: #F5B041;
      --deep-black: #0B0B0D;
      --accent-red: #E63946;
      --neutral-light: #F8F9FA;
      --neutral-border: #E9ECEF;
      --text-dark: #1A1A1A;
      --text-gray: #495057;
      --text-light: #CED4DA;
      --white: #FFFFFF;
      --shadow-card: 0 10px 30px -10px rgba(0,0,0,0.05);
      --shadow-hover: 0 20px 40px -10px rgba(0,0,0,0.12);
      --glass-bg: rgba(255,255,255,0.7);
      --glass-border: rgba(255,255,255,0.3);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-pill: 50px;
      --font-inter: 'Inter', 'Roboto', sans-serif;
      --font-sans: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition-fast: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-dark);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background-color 0.4s ease, box-shadow 0.4s ease;
      background-color: rgba(0,0,0,0.15);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255,255,255,0.25);
    }
    .site-header.scrolled {
      background-color: rgba(11, 11, 13, 0.95);
      backdrop-filter: blur(24px);
      box-shadow: 0 8px 24px rgba(0,0,0,0.3);
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-family: var(--font-sans);
      font-weight: 900;
      font-size: 1.8rem;
      letter-spacing: 0.02em;
      color: var(--white);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      color: var(--primary-yellow);
      font-size: 2rem;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2.5rem;
    }
    .nav-links a {
      font-family: var(--font-sans);
      font-weight: 500;
      font-size: 1rem;
      color: rgba(255,255,255,0.9);
      text-decoration: none;
      transition: color 0.2s;
      letter-spacing: 0.02em;
    }
    .nav-links a:hover {
      color: var(--primary-yellow);
    }
    .cta-btn-nav {
      background-color: var(--primary-yellow);
      color: var(--deep-black);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--radius-pill);
      text-decoration: none;
      transition: var(--transition-fast);
      letter-spacing: 0.05em;
      box-shadow: 0 4px 12px rgba(245,176,65,0.3);
    }
    .cta-btn-nav:hover {
      background-color: var(--accent-red);
      color: white;
      box-shadow: 0 0 20px rgba(245,176,65,0.6);
      transform: translateY(-2px);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
    }
    /* Hero */
    .hero {
      position: relative;
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-attachment: fixed;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(11,11,13,0.8) 0%, rgba(26,26,26,0.7) 100%);
      backdrop-filter: blur(2px);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      margin-top: 40px;
    }
    .hero h1 {
      font-family: var(--font-sans);
      font-size: clamp(2.8rem, 6vw, 5rem);
      font-weight: 900;
      letter-spacing: -0.02em;
      line-height: 1.1;
      color: var(--white);
      margin-bottom: 1.5rem;
    }
    .hero h1 span {
      color: var(--primary-yellow);
    }
    .hero-sub {
      font-size: 1.25rem;
      color: var(--text-light);
      max-width: 650px;
      margin-bottom: 2.5rem;
    }
    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 1.2rem;
    }
    .btn-primary, .btn-ghost {
      padding: 14px 36px;
      border-radius: var(--radius-pill);
      font-weight: 700;
      letter-spacing: 0.05em;
      text-decoration: none;
      transition: var(--transition-fast);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-primary {
      background: var(--primary-yellow);
      color: var(--deep-black);
      box-shadow: 0 8px 20px rgba(245,176,65,0.4);
    }
    .btn-primary:hover {
      background: var(--accent-red);
      color: white;
      box-shadow: 0 0 28px rgba(230,57,70,0.6);
      transform: translateY(-3px);
    }
    .btn-ghost {
      border: 2px solid var(--primary-yellow);
      color: var(--primary-yellow);
      background: transparent;
    }
    .btn-ghost:hover {
      background: var(--primary-yellow);
      color: var(--deep-black);
      transform: translateY(-3px);
    }
    /* 通用区块 */
    section {
      padding: 120px 0;
    }
    .section-title {
      font-family: var(--font-sans);
      font-size: 2.8rem;
      font-weight: 700;
      letter-spacing: -0.01em;
      margin-bottom: 1.2rem;
      color: var(--deep-black);
    }
    .section-lead {
      font-size: 1.2rem;
      color: var(--text-gray);
      max-width: 700px;
      margin-bottom: 3.5rem;
    }
    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 2rem;
    }
    .pain-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-md);
      padding: 2.5rem 2rem;
      transition: var(--transition-fast);
      box-shadow: var(--shadow-card);
    }
    .pain-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
    }
    .pain-icon {
      font-size: 2.5rem;
      color: var(--primary-yellow);
      margin-bottom: 1.5rem;
    }
    .pain-card h3 {
      font-size: 1.6rem;
      font-weight: 700;
      margin-bottom: 0.8rem;
    }
    /* 解决方案交替布局 */
    .solution-block {
      display: flex;
      align-items: center;
      gap: 4rem;
      margin-bottom: 6rem;
    }
    .solution-block.reverse {
      flex-direction: row-reverse;
    }
    .solution-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .solution-img img {
      width: 100%;
      height: auto;
      display: block;
    }
    .solution-text {
      flex: 1;
    }
    .solution-text h3 {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 1rem;
    }
    .text-link {
      color: var(--primary-yellow);
      font-weight: 600;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      margin-top: 1rem;
    }
    /* 数据看板 */
    .dark-bg {
      background-color: var(--deep-black);
      color: white;
      border-radius: var(--radius-md);
      padding: 4rem 2rem;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 2rem;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-inter);
      font-size: 3.5rem;
      font-weight: 900;
      color: var(--primary-yellow);
    }
    /* 证言卡片 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 2rem;
    }
    .testimonial-card {
      background: var(--white);
      border: 1px solid var(--neutral-border);
      border-radius: var(--radius-md);
      padding: 2rem;
      box-shadow: var(--shadow-card);
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--neutral-border);
      padding: 1.5rem 0;
    }
    .faq-question {
      font-weight: 700;
      font-size: 1.2rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      margin-top: 1rem;
      color: var(--text-gray);
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* CTA */
    .cta-section {
      background: url('/assets/images/backpic/back-2.webp') center/cover;
      position: relative;
      text-align: center;
    }
    .cta-overlay {
      background: rgba(11,11,13,0.85);
      padding: 100px 24px;
    }
    .footer {
      background: var(--deep-black);
      color: var(--text-light);
      padding: 60px 0 30px;
    }
    @media (max-width: 1024px) {
      .pain-grid, .testimonial-grid { grid-template-columns: repeat(2,1fr); }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
      .solution-block { flex-direction: column; gap: 2rem; }
    }
    @media (max-width: 768px) {
      .hamburger { display: block; }
      .nav-links { display: none; flex-direction: column; background: var(--deep-black); position: absolute; top:72px; left:0; width:100%; padding:2rem; }
      .nav-links.open { display: flex; }
      .pain-grid, .testimonial-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: 1fr; }
      section { padding: 80px 0; }
    }