An outline is a line that is drawn around elements, OUTSIDE the borders, to make the element "stand out".

CSS has the following outline properties:

• outline-style
• outline-color
• outline-width
• outline-offset
• outline

Note: Outline differs from borders! Unlike border, the outline is drawn outside the element's border, and may overlap other content. Also, the outline is NOT a part of the element's dimensions; the element's total width and height is not affected by the width of the outline.

CSS Outline Style

The outline-style property specifies the style of the outline, and can have one of the following values:

• dotted - Defines a dotted outline
• dashed - Defines a dashed outline
• solid - Defines a solid outline
• double - Defines a double outline
• groove - Defines a 3D grooved outline
• ridge - Defines a 3D ridged outline
• inset - Defines a 3D inset outline
• outset - Defines a 3D outset outline