discourse/plugins/chat/assets/stylesheets/common/chat-modal-create-channel.scss

.chat-modal-create-channel {
  .modal-inner-container {
    width: 500px;
  }

  .choose-topic-results-list {
    max-height: 200px;
    overflow-y: scroll;
  }

  .select-kit.combo-box,
  &__input,
  #choose-topic-title {
    width: 100%;
    margin-bottom: 0;
  }
  .category-chooser {
    .select-kit-selected-name.selected-name.choice {
      color: var(
        --primary-high
      ); // Make consistent with color of placeholder text when choosing topic
    }
  }

  &__hint {
    font-size: var(--font-down-1);
    padding-top: 0.25rem;
    color: var(--secondary-low);
  }

  &__control,
  .edit-channel-control {
    margin-bottom: 1rem;
  }

  &__label-description {
    margin: 0;
    padding-top: 0.25rem;
    color: var(--secondary-low);
    font-size: var(--font-down-1) !important;
  }
}