opening/closing

You can set the open attribute, which will cause the mosaic to open(Determines if the mosaic is open or closed) or close:

const m = document.querySelector('syndigo-mosaic')

m.setAttribute('open', '') // opens the mosaic
m.removeAttribute('open') // closes the mosaic

You can also detect if the mosaic is currently open or closed:

const isMosaicOpen = !!m.getAttribute('open') // true or false