function showError(msg) {
    document.getElementById('data').innerText = msg;
}
function updateTrackInfo(track) {
    if (!track) {
        document.getElementById('track-info').innerText = 'Nothing playing or no active device.';
        return;
    }
    if (track.item) {
        document.getElementById('track-info').innerText =
            `Now Playing: ${track.item.name} by ${track.item.artists.map(a => a.name).join(", ")}`;
    } else {
        document.getElementById('track-info').innerText = 'Nothing playing.';
    }
}
function showControls() {
    document.getElementById('controls').style.display = '';
    document.getElementById('login-btn').style.display = 'none';
}