Border
{border: width style color}The border property lets you set the width, style, and color of all four of an element's borders simultaneously. Any omitted values will revert to their initial values.
Example:
H1 {border: thin solid blue}
If you are using a CSS-enabled browser, this headline has a thin, solid, blue border.
H1 {border: 10px double #32cd32}
If you are using a CSS-enabled browser, this headline has a 10-pixel-wide, double, lime green border.