   <style>
    /* Reset and base */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      background-color: #121212;
      color: #cccccc;
      font-family: 'Inter', sans-serif;
      line-height: 1.6;
      min-height: 100vh;
      display: flex;
      flex-direction: column;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    a:focus-visible {
      outline: 2px solid #4f46e5;
      outline-offset: 2px;
    }

    /* Header */
    .header {
      background: #0d0d0d;
      padding: 20px 60px;
      border-bottom: 1px solid #2a2a2a;
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: sticky;
      top: 0;
      z-index: 1000;
      box-shadow: 0 2px 8px rgba(0,0,0,0.7);
      transition: background-color 0.3s ease;
    }

    .header:hover {
      background-color: #1a1a1a;
    }

    .logo {
      font-size: 1.75rem;
      font-weight: 800;
      color: #e0e0e0;
      display: flex;
      align-items: center;
      gap: 14px;
      user-select: none;
      letter-spacing: 1.2px;
      text-shadow: 0 0 6px #4f46e5;
      cursor: pointer;
      transition: color 0.3s ease;
    }

    .logo img {
      height: 48px;
      width: auto;
      filter: drop-shadow(0 0 3px #4f46e5);
      transition: transform 0.3s ease;
    }

    .logo:hover {
      color: #7c3aed;
    }

    .logo:hover img {
      transform: scale(1.1);
    }

    /* Navigation */
    .nav-menu {
      display: flex;
      gap: 36px;
      list-style: none;
      font-weight: 600;
      font-size: 1rem;
    }

    .nav-menu a {
      color: #999999;
      padding: 10px 0;
      position: relative;
      transition: color 0.3s ease;
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: #7c3aed;
      transition: width 0.3s ease;
      border-radius: 2px;
    }

    .nav-menu a:hover,
    .nav-menu a:focus {
      color: #ffffff;
    }

    .nav-menu a:hover::after,
    .nav-menu a:focus::after {
      width: 100%;
    }

    /* Product Detail Section */
    .product-detail {
      max-width: 900px;
      margin: 80px auto 100px;
      padding: 0 40px;
      display: flex;
      flex-wrap: wrap;
      gap: 40px;
      user-select: none;
    }

    .product-images {
      flex: 1 1 400px;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .main-image {
      width: 100%;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: 0 10px 30px rgba(124, 58, 237, 0.7);
    }

    .main-image img {
      width: 100%;
      height: auto;
      display: block;
      object-fit: cover;
      border-radius: 16px;
      transition: transform 0.3s ease;
    }

    .main-image img:hover,
    .main-image img:focus {
      transform: scale(1.05);
      outline: none;
    }

    .thumbnail-images {
      display: flex;
      gap: 16px;
      justify-content: center;
    }

    .thumbnail-images img {
      width: 80px;
      height: 80px;
      border-radius: 12px;
      object-fit: cover;
      cursor: pointer;
      border: 2px solid transparent;
      transition: border-color 0.3s ease;
    }

    .thumbnail-images img:hover,
    .thumbnail-images img:focus {
      border-color: #7c3aed;
      outline: none;
    }

    .product-info {
      flex: 1 1 400px;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      color: #e0e0e0;
    }

    .product-title {
      font-size: 2.8rem;
      font-weight: 900;
      margin-bottom: 20px;
      letter-spacing: 0.03em;
      text-shadow: 0 0 10px #7c3aed;
    }

    .product-description {
      font-size: 1.2rem;
      color: #a0a0a0;
      line-height: 1.5;
      margin-bottom: 40px;
    }

    .product-specs {
      background: #1a1a1a;
      border-radius: 14px;
      padding: 24px 28px;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.7);
      margin-bottom: 40px;
    }

    .product-specs h3 {
      font-size: 1.6rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: #e0e0e0;
      letter-spacing: 0.02em;
    }

    .product-specs ul {
      list-style: disc inside;
      color: #a0a0a0;
      font-size: 1rem;
      line-height: 1.4;
    }

    .buy-button {
      background: linear-gradient(135deg, #7c3aed, #4c1d95);
      color: white;
      padding: 20px 60px;
      border-radius: 14px;
      font-weight: 700;
      font-size: 1.2rem;
      border: none;
      cursor: pointer;
      box-shadow: 0 8px 20px rgba(124, 58, 237, 0.6);
      transition: all 0.3s ease;
      user-select: none;
      text-align: center;
      display: inline-block;
      text-shadow: 0 0 6px #d8b4fe;
      width: fit-content;
      align-self: start;
      text-decoration: none;
    }

    .buy-button:hover,
    .buy-button:focus {
      background: linear-gradient(135deg, #9d7edd, #5b2eac);
      box-shadow: 0 12px 30px rgba(157, 126, 221, 0.8);
      transform: translateY(-3px);
      outline: none;
    }

    /* Footer */
    .footer {
      text-align: center;
      margin-top: auto;
      padding: 40px 60px;
      border-top: 1px solid #2a2a2a;
      color: #666666;
      font-size: 1rem;
      user-select: none;
      letter-spacing: 0.05em;
      background: #0d0d0d;
      box-shadow: inset 0 1px 3px rgba(255,255,255,0.05);
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .product-detail {
        padding: 0 40px;
        gap: 32px;
      }

      .header {
        padding: 20px 40px;
      }
    }

    @media (max-width: 768px) {
      .header {
        padding: 16px 20px;
      }

      .nav-menu {
        gap: 24px;
        font-size: 0.95rem;
      }

      .product-detail {
        flex-direction: column;
        padding: 0 20px;
        margin: 60px auto 80px;
      }

      .product-title {
        font-size: 2.2rem;
      }

      .product-description {
        font-size: 1.1rem;
      }

      .product-specs h3 {
        font-size: 1.3rem;
      }

      .product-specs ul {
        font-size: 0.95rem;
      }

      .buy-button {
        padding: 16px 48px;
        font-size: 1.1rem;
      }

      .footer {
        padding: 30px 20px;
        font-size: 0.9rem;
      }
    }
  </style>