Check out example codes for "css border different sides". It will help you in understanding the concepts better.

Code Example 1

/*className     property     values: width style color*/
.rightBorder  { border-right: 1px solid black }

.leftBorder   { border-left: 2px dashed red }

.topBorder    { border-top: 3px dotted blue }

.bottomBorder { border-bottom: 4px double yellow }

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