Check out example codes for "add a border to a div css". It will help you in understanding the concepts better.

Code Example 1

p.dotted {border-style: dotted;}
p.dashed 
{border-style: dashed;}
p.solid {border-style: solid;}
p.double 
{border-style: double;}
p.groove {border-style: groove;}
p.ridge 
{border-style: ridge;}
p.inset {border-style: inset;}
p.outset 
{border-style: outset;}
p.none {border-style: none;}
p.hidden {border-style: hidden;}

p.mix {border-style: dotted dashed solid double;}

Code Example 2

border-style: /*Style Prefered*/;

/*Styles can be:

dotted
dashed
solid
double
groove
ridge
inset
outset
nonce
hidden

*/

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