html tutorial - How to place border inside of a div element using CSS - html5 - html code - html form
Answer: Use the CSS box-shadow Property
If you want to place or draw borders within a rectangular box there is a very easy solution — just use the outline property instead of border and move it inside of the element's box using the CSS3 outline-offset property with a negative value.
However, this solution will not work for rounded corner elements.Draw border within a circular box or element with rounded corner using the box-shadow property.
Example
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Setting Border inside DIV Element</title>
<style type="text/css">
.box {
width: 180px;
height: 180px;
background: black;
margin: 20px 50px;
}
.circle {
border-radius: 50%;
}
.inner-border {
border: 10px solid black;
box-shadow: inset 0px 0px 0px 10px red;
box-sizing: border-box; /* Include padding and border in element's width and height */
}
/* CSS3 solution only for rectangular shape */
.inner-outline {
outline: 15px solid yellow;
outline-offset: -30px;
}
</style>
</head>
<body>
<h2>Border inside Rectangular and Circular Shape</h2>
<div class="box circle inner-border"></div>
<div class="box inner-border"></div>
<hr>
<h2>Outline Inside Rectangular Shape</h2>
<div class="box inner-outline"></div>
</body>
</html>