Is it possible to have the elliptical effect for the top only?

From this site, <https://css-tricks.com/almanac/properties/b/border-radius/>, I wanted to copy the effect done with '/'.

```
border-radius: 30px/10px;

```

Except I can't make the effect apply to the top right and left only. Is this possible using border-radius?

```css
.border-radius {
  width: 100px;
  height: 100px;
  background-color: tomato;
  border-radius: 30px/10px;
}
```

```html
<div class="border-radius"></div>
```