Creating a multi-colored border using CSS linear gradient
HTML
<div class='bordered'>Border on all sides</div>
CSS
.bordered {
border: 15px solid;
border-image-source: linear-gradient(to right, red 20%, green 20%, green 40%, blue 40%, blue 60%, maroon 60%, maroon 80%, chocolate 80%);
border-image-slice: 1;
}
The above example would produce a border that comprises 5 different colors. These colors are defined through a linear-gradient.