Support for CSS properties(border-radius here) can be checked by this code:

```
if(document.createElement('test').style.borderRadius===''){
//some code
}

```

but what do I do in case of linear gradients?
The declaration being like:

```
background:linear-gradient(top,bottom,#123,#456);

```

P.S. I don't want to use Modernizr. I want to learn how-to do this.