.ck-content table {
  border-collapse: collapse;
  width: 90%;
}

.ck-content table th {
  background-color: #b9dcff !important; /* dark blue */
  color: #000000 !important;
  font-weight: bold;
  text-align: center;
}

.ck-content table td {
  border: 1px solid #999;
  padding: 5px;
}