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

Code Example 1

#selector{
    /*The format is border:width style color;*/
    border:2px solid grey;
}

Code Example 2

p {
 
border: 5px solid red;
}

Code Example 3

hr {
  border:none;
  border-top:1px dashed #f00;
  color:#fff;
  background-color:#fff;
  height:1px;
  width:50%;
}

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