Border style, width, colour and radius.
✍️ 3 exercises + code challenge in this lessonThe border property draws a line around an element. It combines three values:
border: 2px solid #2563EB; → width, style, colour.
solid, dashed, dotted, double, groove, ridge, inset, outset, none.
border-top, border-right, border-bottom, border-leftborder-radius rounds the corners; 50% on a square makes a circle.Mastering CSS Borders helps you write clean and reliable CSS code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
<style>
p { padding: 10px; margin: 10px 0; }
.solid { border: 3px solid #2563EB; }
.dashed { border: 3px dashed #14B8A6; }
.dotted { border: 3px dotted #E34F26; }
.left { border-left: 8px solid #EAB308; background: #FEFCE8; }
.round { border: 2px solid #071A2F; border-radius: 16px; }
.circle { width: 80px; height: 80px; border-radius: 50%; background: #2563EB; }
</style>
<p class="solid">Solid border</p>
<p class="dashed">Dashed border</p>
<p class="dotted">Dotted border</p>
<p class="left">Only a left border</p>
<p class="round">Rounded corners</p>
<div class="circle"></div>Check what you learned in “CSS Borders”.
Add a 2px solid black border.
div {
border: black;
}
Which property rounds the corners of an element?
Give the box a 3px dashed border and 10px rounded corners.
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