subline/views/shared/controller.js

let changeStrand = (name)=>{
    for(let strand of document.querySelectorAll(".strand")){
        strand.style.display = "none";
    }

    for(let button of document.querySelectorAll(".menu > button")){
        button.classList = "";
        button.onclick = ()=>{changeStrand(`${button.id.slice(0, button.id.indexOf("Btn"))}Strand`)};
    }

    let activeButton = document.querySelector(`#${name.slice(0, name.indexOf("Strand"))}Btn`);
    activeButton.classList = "active";
    activeButton.onclick = undefined;

    document.querySelector(`#${name}`).style.display = "flex";
    window[`${name}Obj`].display();
}