body {
      margin: 0;
      font-family: 'Segoe UI', sans-serif;
      background: #020617;
      color: #e5e7eb;
    }

    header {
      padding: 3rem 1rem;
      text-align: center;
    }

    header h1 {
      font-size: 2.5rem;
      margin-bottom: 0.5rem;
    }

    header p {
      color: #94a3b8;
    }

    .certificates {
      max-width: 1200px;
      margin: auto;
      padding: 2rem;
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 2rem;
    }

    .certificate-card {
      background: #020617;
      border: 1px solid #1e293b;
      border-radius: 16px;
      overflow: hidden;
      transition: 0.4s;
      box-shadow: 0 10px 30px rgba(0,0,0,0.3);
    }

    .certificate-card:hover {
      transform: translateY(-8px);
      border-color: #4f46e5;
    }

    .certificate-card img {
      width: 100%;
      height: 180px;
      object-fit: cover;
    }

    .certificate-content {
      padding: 1.5rem;
    }

    .certificate-content h3 {
      margin: 0 0 0.5rem;
      font-size: 1.2rem;
    }

    .certificate-content span {
      font-size: 0.9rem;
      color: #94a3b8;
    }

    .certificate-content a {
      display: inline-block;
      margin-top: 1rem;
      padding: 0.6rem 1.2rem;
      border-radius: 8px;
      background: #4f46e5;
      color: white;
      text-decoration: none;
      font-size: 0.9rem;
      transition: 0.3s;
    }

    .certificate-content a:hover {
      background: #6366f1;
    }

    footer {
      text-align: center;
      padding: 2rem;
      color: #94a3b8;
      font-size: 0.9rem;
    }