Add a border with the shorthand: border: 1px solid #333;. You can also set border-width, border-style, and border-color separately for finer control. In UI validation and focus states, borders signal errors; watch layout shifts and accessibility contrast, and test across browsers.
How can you add a border around an element?
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Overview
The border property allows developers to define the style, thickness, and color of borders around elements. You can specify each side’s border individually or use the shorthand form to apply all at once.
Property | Purpose | Example |
|---|---|---|
border-width | Sets the thickness of the border. | border-width: 2px; |
border-style | Defines the border’s line pattern. | border-style: solid; |
border-color | Specifies the border color. | border-color: #333; |
border | Shorthand combining width, style, and color. | border: 2px dashed blue; |
Example: Adding a Simple Border
div.box {
border: 3px solid #4CAF50;
padding: 20px;
background-color: #f9f9f9;
}
This creates a 3px solid green border around a <div> while adding internal padding and a light background.
Example: Customizing Each Side
p.note {
border-top: 2px solid black;
border-right: 2px dotted gray;
border-bottom: 2px dashed red;
border-left: 2px double blue;
}
Each side of the paragraph element uses a unique style and color, demonstrating the flexibility of individual border properties.
Border Styles
solid– A continuous line.dashed– Broken dashes.dotted– Circular dots.double– Two parallel lines.groove,ridge,inset,outset– 3D effects based on color shading.
Advanced Tip
You can also use border-radius to round corners or outline for non-space-consuming visual emphasis. Example:border-radius: 10px; creates smooth, rounded corners.
Practical scenario
Add a red border to invalid inputs or a subtle outline around cards for separation.
Common pitfalls
- Adding borders on hover/focus that change element size (layout shift).
- Forgetting
box-sizingso border changes width. - Misordering shorthand values (width, style, color).
Use
outline to avoid layout shifts, but note it does not affect layout. Test focus styles with keyboard navigation.Think of a border like the frame around a picture — it separates your content from the rest of the page and draws attention where needed.
- Use
borderto define a visual frame around elements. - Combine width, style, and color in one shorthand rule.
- Customize each side with individual border properties.
- Enhance design with
border-radiusfor curved edges.