DropdownLink.vue

<template>
  <div class="dropdown-wrapper" :class="{ open }">
    <div class="dropdown-title" @click="toggle">
      <span class="title">{{ item.text }}</span>
      <span class="arrow"></span>
    </div>
    <ul class="nav-dropdown">
      <li
        class="dropdown-item"
        v-for="subItem in item.items"
        :key="subItem.link">
        <h4 v-if="subItem.type === 'links'">{{ subItem.text }}</h4>
        <ul class="dropdown-subitem-wrapper" v-if="subItem.type === 'links'">
          <li
            class="dropdown-subitem"
            v-for="childSubItem in subItem.items"
            :key="childSubItem.link">
            <nav-link :item="childSubItem"></nav-link>
          </li>
        </ul>
        <nav-link v-else :item="subItem"></nav-link>
      </li>
    </ul>
  </div>
</template>

<script>
  import { isExternal, ensureExt } from './util'
  import NavLink from './NavLink.vue'

  export default {
    components: { NavLink },
    data() {
      return {
        open: false
      }
    },
    props: {
      item: {
        required: true
      }
    },
    methods: {
      toggle() {
        this.open = !this.open
      }
    }
  }
</script>

<style lang="stylus">
@import './styles/config.styl'

.dropdown-wrapper
  .dropdown-title
    .arrow
      display inline-block
      vertical-align middle
      margin-top -1px
      margin-left 6px
      width 0
      height 0
      border-left 4px solid transparent
      border-right 4px solid transparent
      border-top 5px solid #ccc
  .nav-dropdown
    .dropdown-item
      color inherit
      line-height 1.7rem
      h4
        margin 0.45rem 0 0
        border-top 1px solid #eee
        padding 0.45rem 1.5rem 0 1.25rem
      .dropdown-subitem-wrapper
        padding 0
        list-style none
        .dropdown-subitem
          font-size 0.9em
      a
        display block
        height 1.7rem
        line-height 1.7rem
        position relative
        border-bottom none
        font-weight 400
        margin-bottom 0
        padding 0 1.5rem 0 1.25rem
        &:hover
          color $accentColor
        &.router-link-active
          color $accentColor
          &::after
            content ""
            width 0
            height 0
            border-left 5px solid $accentColor
            border-top 4px solid transparent
            border-bottom 4px solid transparent
            position absolute
            top calc(50% - 3px)
            left 10px
      &:first-child h4
        margin-top 0
        padding-top 0
        border-top 0

@media (max-width: $MQMobile)
  .dropdown-wrapper
    &.open .dropdown-title
      margin-bottom 0.5rem
    &:not(.open)
      .dropdown-title .arrow
        border-top 4px solid transparent
        border-bottom 4px solid transparent
        border-left 5px solid #ccc
      .nav-dropdown
        display none
    .nav-dropdown
      .dropdown-item
        h4
          border-top 0
          margin-top 0
          padding-top 0
        h4, & > a
          font-size 15px
          height 2rem
          line-height 2rem
        .dropdown-subitem
          font-size 14px
          padding-left 1rem

@media (min-width: $MQMobile)
  .dropdown-wrapper
    &:hover .nav-dropdown
      display block
    .nav-dropdown
      display none
      box-sizing border-box;
      max-height calc(100vh - 2.7rem)
      overflow-y auto
      position absolute
      top 100%
      right 0
      background-color #fff
      padding 10px 0
      border 1px solid #ddd
      border-bottom-color #ccc
      text-align left
      border-radius 0.25rem
      white-space nowrap
      margin 0
</style>