expenses chart component with js

Is there a way I could add the hover states using js and css? I kind of blanked out at that point and would use some insights. The method I've used was to add classes to the days and expenses. The challenge with this is that it becomes pretty complex to now add hover states to the bars.

data.map(item => i
// days =  item.day
// expense = item.amount
// add class to days and set width to div also created for expenses
)