metamask-extension/ui/components/component-library/avatar-token/avatar-token.scss

.mm-avatar-token {
  &--with-halo {
    position: relative;
  }

  &__token-image {
    width: 100%;

    &--blurred {
      filter: blur(20px);
    }

    &--size-reduced {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      width: 62.5%;
      height: 62.5%;
      border-radius: 50%;
    }
  }
}