Understanding Logical Properties And Values

In the past, CSS has tied itself to physical dimensions and directions, physically mapping the placement of elements to the left, right and top and bottom. We float an element left or right, we use the positioning offset properties top, left, bottom and right. We set margins, padding, and borders as margin-top and padding-left. These physical properties and values make sense if you are working in a horizontal, top to bottom, left to right writing mode and direction.
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