Lovable prompts for design: what works, what drifts, and why

The popular Lovable prompt collections are tested on features, where success is binary: the auth flow exists or it doesn't. Design prompts get judged the same way ('did the page change?'), and by that test, 'use a modern dark theme with vibrant accents' passes. The page changed. What nobody re-checks is screen five, where the vibrant accent has slid back toward indigo-500 and the dark theme has re-acquired the default slate ramp, because the instruction lived in a conversation that kept growing. That slide has a name, design drift, and adjective prompts are its main food source.

The mechanism is worth being precise about: Lovable doesn't ignore style instructions, it *approximates* them, and approximations compound. 'Warm' becomes a slightly different warm each generation. A hex value can't drift: it's either #b45309 or it isn't. That's the entire trick behind prompts that hold: replace every adjective with a value.

A durable Lovable design prompt has five parts. Miss one and the model fills the gap with the defaults, which is how apps end up half-distinctive, which reads worse than either extreme.

1. Authority line. One sentence declaring the system below as the single source of truth, and forbidding invented colors or fonts. Without it, later feature prompts outrank the design context.
2. Complete color tokens, both modes. Semantic roles (background, primary, muted-foreground…) with exact values for light *and* dark. Omitting dark mode delegates the whole second theme back to the defaults.
3. A named font pairing with jobs. Which family does headings, which does body, which weights exist. 'Use nice fonts' produces Inter.
4. Scale values. Type scale, spacing, radius. These are the tells that give away a default-built app faster than color does.
5. Rules: the do's and don'ts. A handful of prohibitions ('no purple gradients, no emoji icons, no uniform radius') plus the motifs that make the design recognizably itself.

Make the app look modern and premium, with a dark theme
and vibrant accent colors. Less generic please.

Use #0c0a09 as the app background and #fbbf24 as the primary
accent. Headings in Fraunces (600), body in Inter. Border
radius 2px everywhere. No gradients.

Use the design system below for everything you build in this
project. It is the single source of truth for color, typography,
spacing, and visual style. Do not invent your own palette,
fonts, or component styling.

[ …the kit's full DESIGN.md: 28 semantic tokens in light and
dark, the font pairing, type scale, spacing, radius, shadows,
motifs, do's and don'ts… ]

The third shape is not practical to hand-write: a real system is several hundred decisions. That's the actual reason design-by-prompting stalls. A durable design prompt turns out to be a document, and nobody wants to type a document into a chat box. So we ship every kit as that document: browse the Lovable themes gallery, pick a kit, copy its prompt, paste once.

1. 1

   Starting fresh: paste it as message one

   Paste the full design prompt before describing any feature, so the very first generation is already on-system. Retrofitting a system onto an app built on defaults costs several correction rounds.

2. 2

   For anything long-lived: move it into Knowledge

   Settings → Knowledge is standing context: it applies to every generation without being re-sent, which makes it the drift-resistant home. Chat context ages; Knowledge doesn't.

3. 3

   When drift appears anyway: point at the system, not the symptom

   Say 'follow the design system for the card styling' rather than re-describing the card. Re-describing spawns a second, slightly different truth; pointing re-anchors the original one.