message: CustomSelectOption: major css refactoring; deprecated option and after properties
diff: align-items: center;
  position: relative;
  box-sizing: border-box;
  - padding: 8px 36px 8px 12px;
  + padding: 8px 12px;
  white-space: nowrap;
  user-select: none;
  cursor: pointer;
  }
  .CustomSelectOption__before {
  + flex-shrink: 0;
  margin-right: 7px;
  }
  -.CustomSelectOption__label {
  - overflow: hidden;
  - text-overflow: ellipsis;
  +.CustomSelectOption__main {
  + flex-grow: 1;
  + max-width: 100%;
  + min-width: 0;
  }
  -.CustomSelectOption__description {
  - color: var(--text_secondary);
  +.CustomSelectOption__content {
  + display: flex;
  + align-items: baseline;
  + justify-content: flex-start;
  +}
  +
  +.CustomSelectOption__children {
  + min-width: 0;
  + overflow: hidden;
  + text-overflow: ellipsis;
  }
  .CustomSelectOption__after {
  margin-left: 7px;
  + flex-shrink: 0;
  +}
  +
  +.CustomSelectOption__description {
  + color: var(--text_secondary);
  + text-overflow: ellipsis;
  + overflow: hidden;
  }
  .CustomSelectOption__selectedIcon {
  - position: absolute;
  - top: 15px;
  - right: 12px;
  + margin-left: 8px;
  }
  