.t451m_close_icon svg {
  display: none !important;
}

.t451m_close_icon {
  width: 20px !important;
  height: 20px !important;
  background: url('https://static.tildacdn.com/tild3433-3939-4739-b166-343433366464/free-icon-multiplica.png') center/20px 20px no-repeat !important;
}