Your appearance choice is stored by the browser you made it in, not on your UNI account. Setting dark mode on your laptop changes that laptop's browser and nothing else, which is why your phone opened in light mode. There is nothing broken and nothing to fix. Set it once on each device you use.
Where the switch is
Open the account menu behind your avatar in the top navigation. The appearance row sits inside it as three icons:
- Light.
- Dark.
- System. UNI follows whatever your device is set to, and flips live when the device flips, including on a schedule your phone or laptop runs at sunset.
The change applies straight away across every part of UNI in that browser. There is no save step.
The choice is stored by the browser, so it is per device
The setting is written to the browser's own local storage, under the name uni-xyz-theme. That has a few consequences worth knowing before you go looking for a setting that does not exist:
- Each device keeps its own choice. Laptop, phone and tablet are three separate records.
- Each browser on the same device keeps its own choice. Chrome and Safari on one laptop do not share it.
- Signing in does not carry it over. It is not part of your account, so a new device starts from the default no matter who signs in.
- A private or incognito window starts fresh and forgets the choice when you close it.
- Clearing your browsing data for uni.xyz resets it back to the default.
The default is System, not Light
A browser that has never been given a choice uses System. If your device is set to dark, UNI will already be dark there without you touching anything. If your device is set to light and you want UNI dark regardless, pick Dark rather than leaving it on System.
That is also the closest thing to a setting that does follow you. Most phones and laptops sync their own appearance setting across your devices through your Apple or Google account. If you set that at the device level and leave UNI on System everywhere, UNI matches it everywhere.
If dark mode does not stick on one device
A choice that resets every visit on a single device usually means that browser is discarding site data on close, or you are browsing privately. Check whether the browser is set to clear cookies and site data on exit, and try a normal window.