I am trying to create a website and wanted to make sure about all the browser but my CSS is not working in IE please tell whats wrong with my CSS.
Which of that is not supporting in IE
my CSS

```
.ui-widget-header {
    border: 1px solid #E1712B !important;
    background-image:linear-gradient(to bottom, #F8B84B 30%,#F7AF39 70%);
    color: #ffffff;
    font-weight: bold;
}

```