schon/storefront/app/components/base/header/catalog.vue

<template>
  <div class="catalog" ref="blockRef">
    <button
        @click="setBlock(!isBlockOpen)"
        class="catalog__button"
        :class="[{ active: isBlockOpen }]"
    >
      {{ t('header.catalog.title') }}
      <span>▽</span>
    </button>
    <div class="container">
      <div class="categories" :class="[{active: isBlockOpen}]">
        <div class="categories__block" v-if="categories.length > 0">
          <div class="categories__left">
            <p
                v-for="category in categories"
                :key="category.node.uuid"
                :class="[{ active: category.node.uuid === activeCategory.uuid }]"
                @click="setActiveCategory(category.node)"
            >
              {{ category.node.name }}
            </p>
          </div>
          <div class="categories__main">
            <div
                class="categories__main-block"
                v-for="mainChildren in activeCategory.children"
                :key="mainChildren.uuid"
            >
              <nuxt-link-locale
                  :to="`/catalog/${mainChildren.slug}`"
                  class="categories__main-link"
                  @click="setBlock(false)"
              >
                {{ mainChildren.name }}
              </nuxt-link-locale>
              <div class="categories__main-list">
                <nuxt-link-locale
                    v-for="children in mainChildren.children"
                    :key="children.uuid"
                    :to="`/catalog/${children.slug}`"
                    @click="setBlock(false)"
                >
                  {{ children.name }}
                </nuxt-link-locale >
              </div>
            </div>
          </div>
        </div>
        <div class="categories__empty" v-else><p>{{ t('header.catalog.empty') }}</p></div>
      </div>
    </div>
  </div>
</template>

<script setup lang="ts">
import type {ICategory} from '@types';
import {onClickOutside} from '@vueuse/core';

const { t } = useI18n();
const categoryStore = useCategoryStore();

const categories = computed(() => categoryStore.categories);

const isBlockOpen = ref<boolean>(false);
const setBlock = (state: boolean) => {
  isBlockOpen.value = state;
};

// TODO: add loading state

const blockRef = ref(null);
onClickOutside(blockRef, () => setBlock(false));

const activeCategory = ref<ICategory>(categories.value[0]?.node);
const setActiveCategory = (category: ICategory) => {
  activeCategory.value = category;
};
</script>

<style lang="scss" scoped>
.catalog {
  &__button {
    cursor: pointer;
    border-radius: $less_border_radius;
    background-color: rgba($primary, 0.2);
    border: 1px solid $primary;
    padding: 5px 20px;
    display: flex;
    align-items: center;
    gap: 10px;

    color: $primary;
    font-size: 16px;
    font-weight: 600;

    @include hover {
      background-color: $primary;
      color: $main;
    }

    & span {
      font-size: 26px;
    }

    &.active {
      background-color: $primary;
      color: $main;

      & span {
        transform: rotate(-180deg);
      }
    }
  }
}

.container {
  position: absolute;
  left: 50%;
  top: 110%;
  transform: translateX(-50%);
  width: 100%;
}

.categories {
  border-radius: $less_border_radius;
  width: 100%;
  background-color: $main;
  box-shadow: 0 0 15px 1px $secondary;
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.2s ease;
  overflow: hidden;

  &.active {
    grid-template-rows: 1fr;
  }

  & > * {
    min-height: 0;
  }

  &__block {
    display: grid;
    grid-template-columns: 20% 80%;
    max-height: 50vh;
  }

  &__columns {
    & div {
      padding: 20px 50px;
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      grid-column-gap: 30px;
      grid-row-gap: 5px;

      & p {
        cursor: pointer;
        padding: 5px 20px;

        font-size: 16px;
        font-weight: 600;

        @include hover {
          color: $primary;
        }
      }
    }
  }

  &__left {
    flex-shrink: 0;
    padding-block: 10px;
    overflow: auto;

    & p {
      cursor: pointer;
      flex-shrink: 0;
      padding: 10px;
      border-left: 3px solid $main;
      font-weight: 700;

      @include hover {
        color: $primary;
      }

      &.active {
        border-color: $primary;
        color: $primary;
      }
    }
  }

  &__main {
    padding: 20px;
    border-left: 2px solid $primary_dark;
    overflow: auto;

    &-block {
      padding-bottom: 15px;
      border-bottom: 1px solid #eeeeee;
      margin-bottom: 15px;

      &:last-child {
        border-bottom: none;
        margin-bottom: 0;
      }
    }

    &-link {
      position: relative;
      width: fit-content;
      cursor: pointer;

      font-weight: 600;
      font-size: 16px;

      &::after {
        content: "";
        position: absolute;
        bottom: -2px;
        left: 0;
        height: 2px;
        width: 0;
        transition: all .3s ease;
        background-color: $primary;
      }

      @include hover {
        &::after {
          width: 100%;
        }
      }
    }

    &-list {
      margin-top: 10px;
      display: grid;
      grid-template-columns: repeat(3,1fr);
      grid-column-gap: 30px;
      grid-row-gap: 5px;

      & a {
        cursor: pointer;

        font-size: 14px;

        @include hover {
          color: $primary;
        }
      }
    }
  }

  &__empty {
    & p {
      padding: 20px;
      text-align: center;
      font-size: 16px;
      font-weight: 600;
    }
  }
}
</style>