I know this question may be duplicated or asked several times. But I'm so new in Vue and I'm not able to find a clear question. How can I read/write a variable from the app into the components?
All I see around they are passing values from the parent component into the child component. This seems like is not working in this case.
This is the structure of my app, I would like to keep this structure.

```
let app = Vue.createApp({
    components:['contrib'],
    data(){
        return{
            contButton:"first value",
        }
    },
    methods: {
        someMethods:{
        },
    },
})

app.component('contrib',{
    props:['contButton'],
    template: `
    <div>
        <button class="button is-small" id="myBtn" @click="showCont">{{contButton}}</button>
    </div>
    `,
    data(){
        return{
            newCont:null,
        }
    },
    methods:{
            showCont() {
            this.newCont=this.contButton
            console.log(this.newCont)
        },
    }
})  

app.mount('#app')

```