Get styles

el.style

Or

el.getAttribute("style")
// "left: 321px; top: 69px; visibility: hidden;"

Get style

el.style.left

Or

el.getStyle('left')
// "321px"

Set style

From setProperty docs MDN.

el.style.setProperty('color', 'red')

I could not get el.setStyle('color', 'red') to work.