Tooltip

◎ Tooltip

- .tooltiptext의 margin-left > width:100px + padding: 8px 

         = (100px / 2) + 8px 

         = 58px > margin-left

- margin-left: (width/2) + padding

- tooltip & arrow tooltip

right	right-arrow
top: -5px  left: 105%	top: 50% right: 100%
left	left-arrow
top: -5px right: 105%	top: 50% left: 100%
top	top-arrow
width: 120px bottom: 100% left: 50% margin-left: -60px	top: 100% left: 50%
bottom	bottom-arrow
width: 120px top: 100% left: 50% margin-left: -60px	bottom: 100% left: 50%

- arrow (ex. bottom-arrow)

- create arrow (using border)

- .tooltiptext::after 

- ex. bottom-tooltip