excess whitespace

```
    @media (min-width: 600px) {
        slot {
            max-width:700px;
        }
        ::slotted(a) {
            flex: calc(50% - var(--margin) * 2);
        }
    }

```

result

```
@media (min-width:600px){slot{max-width:700px}::slotted(a){flex:calc(50% - var( -- margin) * 2)}}
```

whitespace between "--" and "margin" broke the style