Why is store not defined?

index.js

 import Vue from "vue"
    import Vuex from "vuex"
    
    Vue.use(Vuex)
    
    export default new Vuex.Store({
      state: {
        city: ""
      }
    })

main.js

  import Vue from "vue"
import App from "./App"
import router from "./router"
import fastClick from "fastclick"
import VueAwesomeSwiper from "vue-awesome-swiper"
import store from "./store"
import "styles/reset.css"
import "styles/border.css"
import "styles/iconfont.css"
import "swiper/dist/css/swiper.css"
Vue.config.productionTip = false
fastClick.attach(document.body)
Vue.use(VueAwesomeSwiper)

/* eslint-disable no-new */
new Vue({
  el: "-sharpapp",
  router,
  store,
  components: {App},
  template: "<App/>"
})

Header.vue

<template>
    <div class="header">
        <div class="header-left">
            <div class="iconfont back-icon"></div>
        </div>
        <div class="header-input">
            <span class="iconfont"></span>
            //
        </div>
        <router-link to="/city">
            <div class="header-right">
                {{this.$store.state.city}}
                <span class="iconfont arrow-icon"></span>
            </div>
        </router-link>
    </div>
</template>

<script>
export default {
  name: "HomeHeader"
}
</script>

<style lang="stylus" scoped>
    @import "~styles/variables.styl";
    .header
        display: flex
        line-height: $headerHeight
        background: $bgColor
        color:-sharpfff
        .header-left
            width: .64rem
            float: left
            .back-icon
                text-align: center
                font-size: .4rem
        .header-input
            flex: 1
            height: .64rem
            line-height: .64rem
            margin-top: .12rem
            margin-left: .2rem
            padding-left: .2rem
            background: -sharpfff
            border-radius: .1rem
            color: -sharpccc
        .header-right
            width: 1.24rem
            float: right 
            text-align: center 
            color: -sharpfff
            .arrow-icon
                margin-left: -.04rem
                font-size: .2rem
</style>


Jun.29,2021
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