「border-style」属性の一例
solid
border: 4px solid blue;
double
border: 4px double red;
hidden
border: 4px hidden black;
groove
border: 6px groove black;
ridge
border: 4px ridge red;
inset
border: 8px solid white;
outset
border: 8px solid white;
dotted
border: 4px dotted red;
dashed
border: 4px dashed black;