Inverted themes with light-dark()

We rolled out adaptive light-dark() support on our design system themes and it’s been a delightful upgrade. Creating light and dark variable sets isn’t difficult, but delivery has trade-offs. Most apps that do this probably ship both sets of token values in a single stylesheet. That’s fine until you have multiple kilobytes of duplicate definitions. To get around the performance problems we built two separate stylesheets –which is also not great– but my coworker Zacky found a good trick with <link disabled> to make it tolerable. Ultimately, we wanted to offer a single stylesheet for our human (and agent) friends to control theming.