p5.js-web-editor/client/styles/components/_quick-add.scss

.quick-add {
  width: auto;
  min-width: #{600 / $base-font-size}rem;
  padding: #{24 / $base-font-size}rem;
}

.quick-add__item {
  display: flex;
  align-items: center;
  height: #{64 / $base-font-size}rem;
  padding-right: #{24 / $base-font-size}rem;

  button, a {
    @include themify() {
      color: getThemifyVariable('primary-text-color');
    }
  }
}

.quick-add__item:nth-child(odd) {
  @include themify() {
    background: getThemifyVariable('table-row-stripe-color');
  }
}

.quick-add__item-toggle {
  display: flex;
  align-items: center;

  flex: 1;
}

.quick-add__icon {
  display: inline-block;
  margin-right:#{15 / $base-font-size}rem;
  width:#{35 / $base-font-size}rem;
  height:#{35 / $base-font-size}rem;
  @include icon();
  @include themify() {
    & path {
      fill: getThemifyVariable('dropdown-color');
    }

    & svg {
      width:#{35 / $base-font-size}rem;
      height:#{35 / $base-font-size}rem;
    }
  }
}

.quick-add__icon > * {
  display: none;
}

.quick-add__in-icon {
  display: inline-block;

  & svg {
    opacity: 0.3;
  }
}

.quick-add__icon--in-collection .quick-add__in-icon svg {
  opacity: 1;
}

.quick-add__add-icon {
  transform: rotate(45deg);
}

.quick-add__item-toggle:hover {
  .quick-add__in-icon {
    display: none;
  }

  .quick-add__icon--in-collection {
    .quick-add__remove-icon {
      display: inline-block;
    }

    .quick-add__add-icon {
      display: none;
    }
  }

  .quick-add__icon--not-in-collection {
    .quick-add__add-icon {
      display: inline-block;
    }

    .quick-add__remove-icon {
      display: none;
    }
  }
}