.uc-myform {
  position: fixed !important;
  top: 50% !important;
  left: 50% !important;
  transform: translate(-50%, -50%) !important;
  z-index: 2000000 !important; /* больше чем у FD301 */
  max-width: 500px;
  width: 90%;
  background: #fff;
  padding: 30px;
  border-radius: 20px;
  box-shadow: 0 0 40px rgba(0,0,0,0.3);
  display: none !important;
}
.t-feed__post-popup.t-popup_show {
  z-index: 1000 !important;
}