Extract Shadow Styles for an AI Coding Agent

Contents

• [Use a repeatable extraction method](#use-a-repeatable-extraction-method)
• [Check what the page actually uses](#check-what-the-page-actually-uses)
• [Turn observations into agent-ready CSS](#turn-observations-into-agent-ready-css)
• [Verify before you ship](#verify-before-you-ship)
• [Use this in your AI agent](#use-this-in-your-ai-agent)

To extract shadow styles for an AI coding agent, inspect the live page at the component level, record each shadow's role and values, then give the agent a small, named token set rather than a pile of isolated CSS declarations. The safest result separates observed values from your own interpretation, so the agent can reproduce the page without pretending that an inferred design system is official.

Use a repeatable extraction method

Start with the surfaces that visibly use elevation: cards, menus, dialogs, popovers, sticky headers, image frames, and focused controls. For each one, capture:

• The component or surface name
• The shadow role, such as card, overlay, focus, or floating action
• The CSS declaration, including offsets, blur, spread, and color alpha
• Whether the shadow appears in the default, hover, focus, or open state
• The background behind the component
• The radius and border used with it

Do not record only box-shadow. A shadow can look completely different on a white page, a tinted surface, or a dark canvas. Save the surrounding background and border values too, then compare the component at its normal size and in its active state.

A useful naming scheme is:

If two components use the same value, give them the same token. If they look similar but use different values, keep both until you know whether the difference is intentional.

Check what the page actually uses

Review the page structure before copying values. A shadow may belong to a nested wrapper rather than the visible card itself, and a screenshot can hide a subtle border or gradient that changes the result. Check desktop and mobile states when both matter. Open menus and dialogs instead of extracting only the initial view.

For each candidate shadow, ask three questions:

1. Does it appear on the element you plan to recreate?
2. Does it remain visible against the same background in your implementation?
3. Does it signal a different layer, state, or interaction?

The examples below are useful for comparing overall visual treatment. The captured Linear references show a near-black canvas, muted dividers, compact controls, and one cool accent. Their typography evidence identifies Inter in regular and medium weights. Those details can help you judge whether your extracted shadows belong in a restrained interface, but they do not establish Linear's shadow values.

Turn observations into agent-ready CSS

Give your coding agent a short table before asking it to implement anything:

Then provide implementation rules. Tell the agent to preserve the original alpha, avoid replacing multiple shadows with one generic shadow, keep state-specific values separate, and use the measured background when checking the result. Ask it to place tokens in the project's existing theme file rather than scattering them through component files.

For Tailwind, map the values to named utilities or theme variables. For plain CSS, keep the source declaration intact and expose it through custom properties. For a component library, record which component consumes each token. This makes later changes safer and lets you compare the recreation with the source page one surface at a time.

Verify before you ship

Render the recreated components at the same approximate size and background as the source. Compare the edge immediately around the component, not just the full screenshot. Look for four common mistakes: a shadow that is too dark, blur that spreads too far, a missing border that makes the shadow seem wrong, or a focus shadow that has been incorrectly reused as a resting shadow.

If the match is close but not exact, adjust one variable at a time. Change alpha before blur when the edge shape is correct but the surface feels too heavy. Change offset when the shadow seems detached. Change spread when the shadow hugs or overshoots the component. Keep a note of every adjustment so the final token remains explainable.

Use this in your AI agent

> Inspect the captured website for every visible shadow on cards, menus, dialogs, sticky surfaces, image frames, and focused controls. Return a table with component, state, shadow role, exact CSS value, background, border, radius, and confidence. Group repeated values into named tokens, keep state-specific shadows separate, and generate implementation-ready CSS custom properties plus a short mapping for the project's components. Clearly label observed values versus recommendations, and include a verification checklist for comparing the recreated surfaces at matching size and background. > > Install Fudge for your AI agent to inspect the captured page and turn the checked observations into implementation notes.

Ask for a state-by-state inventory instead of one visual summary. Include the default page, hoverable cards, focused fields, open menus, dialogs, sticky elements, and any responsive layout that changes the surface treatment.

A strong request tells the agent to identify the element, state, background, border, radius, and exact shadow declaration. It should also say whether the value was directly observed or estimated from appearance. That distinction matters when a shadow is subtle or when several nested wrappers contribute to the visible result.

Have the agent return one table first, then a token proposal. The table preserves the evidence. The token proposal makes the result usable in code. Ask it not to merge values merely because they look similar, and not to rename a focus shadow as a card shadow without checking the interaction state.

Finally, require a short comparison checklist. It should cover opacity, offset, blur, spread, edge sharpness, and the background behind each surface. This gives you a practical review step before the agent edits the theme or component files.

Keep the file small, named, and traceable. Each token should have a clear role such as card, raised surface, floating menu, dialog, or focus ring. Store the original CSS value, not only a converted design-tool number, so another developer can compare it with the inspected page.

A useful structure includes the token name, value, supported states, components that use it, source URL or capture reference, and confidence. Add a note when a value is an approximation or when the visible effect comes from both a border and a shadow. If the project uses light and dark themes, keep the theme-specific values together rather than hiding them in separate component files.

Also include a short usage rule. For example, cards may use the card token at rest, menus may use the floating token only while open, and focus treatment should not be reused for elevation. If your agent exports CSS, have it emit custom properties first, then component declarations that consume those properties. That keeps future tuning centralized and prevents duplicated shadow strings.

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