:root {
    --bg-dark: #14161a;
    --bg-card: #1e2128;
    --text-main: #f2f3f5;
    --text-sub: #a3a9b6;
    --accent: #ff5e3a;
    --accent-hover: #e04a28;
    --border: #2f3540;
    --radius: 12px;
    --max-width: 1200px;
  }
  * { margin: 0; padding: 0; box-sizing: border-box; }
  body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
  }
  a { text-decoration: none; color: inherit; }
  img { max-width: 100%; display: block; }
  .container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }

  /* Header */
  header {
    position: fixed;
    top: 0; left: 0; right: 0;
    background: rgba(20, 22, 26, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    z-index: 100;
  }
  .header-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 60px;
  }
  .logo-group { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; }
  .logo-group img { height: 32px; border-radius: 6px; }
  .nav-links { display: flex; gap: 20px; font-size: 15px; color: var(--text-sub); }
  .nav-links a:hover { color: var(--accent); }
  
  /* Mobile Nav */
  .mobile-menu-btn { display: none; background: none; border: none; color: var(--text-main); font-size: 24px; cursor: pointer; }

  /* Buttons */
  .btn {
    display: inline-block; padding: 12px 28px; background-color: var(--accent); color: #fff;
    border-radius: 30px; font-weight: 600; text-align: center; transition: background 0.3s, transform 0.2s;
  }
  .btn:hover { background-color: var(--accent-hover); transform: translateY(-2px); }
  .btn-large { font-size: 18px; padding: 16px 40px; }
  .btn-outline {
    background: transparent; border: 2px solid var(--accent); color: var(--accent);
  }
  .btn-outline:hover { background: var(--accent); color: #fff; }

  /* Hero */
  .hero {
    padding: 100px 0 60px;
    position: relative;
    overflow: hidden;
  }
  .hero-bg {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    background: radial-gradient(circle at 70% 30%, rgba(255, 94, 58, 0.15), transparent 60%);
    z-index: -1;
  }
  .hero-inner {
    display: flex; align-items: center; justify-content: space-between; gap: 40px;
  }
  .hero-text { flex: 1; max-width: 540px; }
  .hero-tag {
    display: inline-block; padding: 6px 14px; background: rgba(255, 94, 58, 0.15); color: var(--accent);
    border-radius: 20px; font-size: 14px; margin-bottom: 20px; font-weight: 600;
  }
  .hero h1 { font-size: 42px; line-height: 1.2; margin-bottom: 20px; }
  .hero p { font-size: 18px; color: var(--text-sub); margin-bottom: 32px; }
  .hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
  
  .hero-visual { flex: 1; position: relative; display: flex; justify-content: center; }
  .hero-covers {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px;
    transform: rotate(-3deg) scale(1.05);
  }
  .hero-covers img {
    width: 100%; border-radius: var(--radius); box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    object-fit: cover; aspect-ratio: 3/4;
  }
  .hero-covers img:nth-child(2) { transform: translateY(30px); }
  .hero-covers img:nth-child(3) { transform: translateY(-20px); }
  
  /* Section Common */
  section { padding: 80px 0; }
  .section-header { text-align: center; margin-bottom: 50px; }
  .section-header h2 { font-size: 32px; margin-bottom: 12px; }
  .section-header p { color: var(--text-sub); font-size: 16px; max-width: 600px; margin: 0 auto; }

  /* Feature / AI Section */
  .feature-split {
    display: flex; align-items: center; gap: 60px;
  }
  .feature-text { flex: 1; }
  .feature-text h2 { font-size: 32px; margin-bottom: 20px; }
  .feature-text p { color: var(--text-sub); margin-bottom: 20px; font-size: 16px; }
  .feature-list { list-style: none; margin-bottom: 30px; }
  .feature-list li {
    display: flex; align-items: center; gap: 12px; margin-bottom: 12px; font-size: 16px;
  }
  .feature-list li::before {
    content: "✓"; color: var(--accent); font-weight: bold; font-size: 20px;
  }
  .feature-image { flex: 1; }
  .feature-image img { border-radius: var(--radius); box-shadow: 0 10px 30px rgba(0,0,0,0.4); }

  /* Grid Cards */
  .grid-cards {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 20px;
  }
  .card {
    background: var(--bg-card); border-radius: var(--radius); overflow: hidden;
    transition: transform 0.3s;
  }
  .card:hover { transform: translateY(-5px); }
  .card img { width: 100%; aspect-ratio: 3/4; object-fit: cover; }
  .card-info { padding: 12px; }
  .card-info h3 { font-size: 16px; margin-bottom: 6px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .card-info p { font-size: 13px; color: var(--text-sub); }

  /* Horizontal Scroll */
  .scroll-row {
    display: flex; gap: 16px; overflow-x: auto; padding-bottom: 20px; scrollbar-width: thin;
  }
  .scroll-row::-webkit-scrollbar { height: 6px; }
  .scroll-row::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
  .scroll-item {
    flex: 0 0 160px; border-radius: var(--radius); overflow: hidden;
  }
  .scroll-item img { width: 100%; aspect-ratio: 3/4; object-fit: cover; }
  .scroll-item h3 { font-size: 15px; margin-top: 8px; text-align: center; }

  /* Steps */
  .steps-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px;
  }
  .step-card {
    background: var(--bg-card); padding: 30px; border-radius: var(--radius); text-align: center;
    border: 1px solid var(--border);
  }
  .step-num {
    width: 50px; height: 50px; background: var(--accent); color: #fff; border-radius: 50%;
    display: flex; align-items: center; justify-content: center; font-size: 24px; font-weight: bold;
    margin: 0 auto 20px;
  }
  .step-card h3 { font-size: 20px; margin-bottom: 12px; }
  .step-card p { color: var(--text-sub); font-size: 15px; }

  /* CTA Banner */
  .cta-banner {
    background: linear-gradient(135deg, rgba(255,94,58,0.1) 0%, rgba(255,94,58,0.02) 100%);
    border: 1px solid var(--accent); border-radius: var(--radius);
    padding: 60px 20px; text-align: center; margin: 40px auto; max-width: 800px;
  }
  .cta-banner h2 { font-size: 36px; margin-bottom: 20px; }
  .cta-banner p { color: var(--text-sub); font-size: 18px; margin-bottom: 30px; }

  /* Footer */
  footer {
    border-top: 1px solid var(--border); padding: 30px 0; text-align: center;
    font-size: 13px; color: var(--text-sub);
  }
  footer p { margin-bottom: 8px; }
  footer a { color: var(--text-sub); }
  footer a:hover { text-decoration: underline; }
  .update-time { font-size: 12px; color: #666; margin-top: 10px; }

  /* Responsive */
  @media (max-width: 1024px) {
    .hero h1 { font-size: 36px; }
    .feature-split { flex-direction: column; gap: 40px; }
    .hero-inner { flex-direction: column; text-align: center; }
    .hero-text { max-width: 100%; }
    .hero-actions { justify-content: center; }
    .hero-visual { margin-top: 40px; }
    .hero-covers { transform: none; max-width: 400px; }
    .hero-covers img:nth-child(2), .hero-covers img:nth-child(3) { transform: none; }
    .steps-grid { grid-template-columns: 1fr; }
  }

  @media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-links.active {
      display: flex; flex-direction: column; position: absolute;
      top: 60px; left: 0; right: 0; background: var(--bg-dark);
      padding: 20px; border-bottom: 1px solid var(--border);
    }
    .mobile-menu-btn { display: block; }
    .hero { padding: 80px 0 40px; }
    .hero h1 { font-size: 28px; }
    .hero p { font-size: 16px; }
    .btn-large { font-size: 16px; padding: 14px 30px; width: 100%; }
    .hero-actions { flex-direction: column; }
    .section-header h2 { font-size: 24px; }
    .feature-text h2 { font-size: 26px; }
    .cta-banner h2 { font-size: 28px; }
    .grid-cards { grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .card-info h3 { font-size: 14px; }
  }