Codeflaps

Multi coloured rainbow border with CSS

Creating a multi coloured border is bit complicated for the beginners. Hopefully this tutorial will help them out. Though I am calling it a rainbow like border, it can have more than seven colors. You can add as many colors as you want. I am sharing this tutorial only to give you an idea about rainbow border, it will be better if you experiment more.

Screenshot of multi coloured border


In order to create this rainbow border I have used the CSS linear gradient property. I won't discuss about CSS gradient property here in this tutorial, I will come up with a new article on this topic soon . If you are not familiar with CSS gradient properties than you can read this article on CSS-tricks

The HTML used

The html markup used in this tutorial
<body>
<div id="box">
</div>
</body>

The CSS used 

Following is the CSS used in this tutorial. I have used pseudo class after to create the rainbow border, also used the absolute position, giving it a position zero from left, right and bottom.
#box{margin: 40px auto; background-color:#3a3a3a; width: 50%; height: 100px; position: relative;}
#box:after {
  content: "";
  position: absolute;
  left: 0px;
  right:0px;
  bottom: 0px;
  height: 7px;
  background-image: -webkit-linear-gradient(0deg, #F78181 40px, #BEF781 40px, #BEF781 70px,#58ACFA 70px, #58ACFA 100px, #9b59b6 100px,#9b59b6 130px,#BDBDBD 130px,#BDBDBD 160px,#F3F781 160px,#F3F781 190px,#58FAD0 190px,#58FAD0 220px,#FE642E 220px,#FE642E 250px,#DA81F5 250px,#DA81F5 280px,#886A08 280px,#886A08 310px,#088A29 310px,#088A29 340px);
  background-size: 340px;
}

My implementing this CSS you can easily have a rainbow border at the bottom of a particular div element.
If you are interested in showing the rainbow border at the top of a section then simply do the following changes.

#box:after ---> #box:before
bottom:0px; ---> top:0px;

Wrap Up

Though I have shared all the required CSS for creating a rainbow border, try to understand the codes first, it will help you creating more cool stuffs in future. If you are not getting this tutorial properly then you can ask me anytime.