The @import: rule imports another stylesheet into the current style sheet. It should appear right at the start of the style sheet before any of the rules, and its value is a URL.
You can write it like this:
<style> <!-- @import "mystyle.css"; or @import url("mystyle.css"); .......other CSS rules ..... --> </style>
The significance of the @import rule is that it allows you to develop your style sheets with a modular approach. You can create various style sheets and then include them wherever you need them.