#openPdfBtn {
  background-color: #1e88e5; /* Professional blue */
  color: #ffffff;
  border: none;
  padding: 12px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 4px;
  cursor: pointer;
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

#openPdfBtn:hover {
  background-color: #1565c0;
  box-shadow: 0 4px 10px rgba(30, 136, 229, 0.4);
}

#openPdfBtn:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(30, 136, 229, 0.35);
}