https://stackoverflow.com/questions/58589741/angular-8-hide-divs-and-show-div-on-button-click
div1:boolean=true;
    div2:boolean=true;
    div3:boolean=true;
    div1Function(){
        this.div1=true;
        this.div2=false;
        this.div3=false
    }
    div2Function(){
        this.div2=true;
        this.div1=false;
        this.div3=false
    }
    div3Function(){
        this.div3=true;
        this.div2=false;
        this.div1=false
    }
