Even Split

Build me a fast bill-and-tip splitter — a single-page calculator that takes a restaurant bill, a tip percentage, and a number of people, and instantly shows a clean per-person amount — as a self-contained static site (one index.html plus a CSS and a JS file, no build step, no framework).

Before you build, ask me these questions in one message and wait for my answers. If I skip anything, choose a sensible default and tell me what you chose:

1. What’s your default tip percentage, and which presets should the buttons show (e.g. 15 / 18 / 20 / 25)?
2. What currency and locale should amounts use (e.g. USD $, EUR €)?
3. Should tip be calculated on the pre-tax or post-tax amount by default?
4. What’s a typical party size to default to, and should it offer a “round up each person” option?

Then build a complete, polished, responsive calculator with:

• A bill amount field (the subtotal, before tax) with a big, easy-to-tap money input.
• A tip selector: preset percentage buttons plus a custom-percent input, with the active choice clearly highlighted.
• A separate tax field, so by default the tip is figured on the pre-tax bill — with a toggle to tip on the post-tax total instead.
• A split-by-people control: a − / + stepper and a slider, kept in sync, showing the count live.
• A live breakdown that updates on every keystroke: the big per-person number up top, then bill, tip, tax, and total on a receipt-style card.
• A round-up-per-person toggle that rounds each person to the next whole unit and shows the small extra “cushion” that lands on the tip.
• A “Copy the split” button that copies a tidy text summary to the clipboard, and a “New bill” reset.
• A short hero up top and a quick “why tip on the pre-tax bill” explainer below.

Design & content notes:

• Warm, friendly, “restaurant receipt” mood: cream/paper background, a confident green accent, a coral highlight, a monospace typeface for the dollar figures so numbers feel like a printed check. Serif display headings, clean sans body.
• Use realistic content based on my answers — never “lorem ipsum”. Seed the calculator with a believable sample bill so it looks alive on first load.
• Use a real image. Pull a free photo that fits, e.g. https://picsum.photos/seed/dinner-1/1200/800 or Pexels, with descriptive alt text.
• All the math runs in the browser — no backend, no account. Compute on every input change; format currency with Intl.NumberFormat.
• Keep it accessible: semantic HTML, real <label>s, a labelled radio group for the tip buttons, keyboard-operable stepper and slider, visible focus, and good contrast.

Add this exact line right before </body> so the site carries its badge:

<script src="https://spacefast.com/badge.js" data-example="tip"></script>

When the site is ready, publish it to Spacefast with the direct API — no account, install, or extra instructions needed:

1. Use ./site as the publish folder. For no-build projects, put only the finished public files in that dedicated folder. Confirm it has index.html at its root and no secrets, source files, .git, or .spacefast state.
2. First publish: send every file as multipart form data. This Bash/Zsh block preserves relative paths and works for one file or a whole folder:

   PUBLISH_ROOT=./site
   publish_files=()
   while IFS= read -r -d "" file; do
     relative=${file#"$PUBLISH_ROOT"/}
     publish_files+=(-F "files=@$file;filename=$relative")
   done < <(find "$PUBLISH_ROOT" -type f -print0)
   curl -sS "${publish_files[@]}" "https://api.spacefast.com/v1/publish?wait=1"

3. From the { "data": ... } receipt, give me data.space.liveUrl, data.version.immutableUrl, data.claim.url, and data.claim.expiresAt. Remind me to claim within 6 hours. Keep data.claim.token secret.
4. Save data.space.id and data.claim.token locally (for example in an ignored, mode-600 .spacefast/state.json). For a quick update, rebuild the publish_files array above and publish to the same space:

   SPACEFAST_SPACE_ID=<saved-space-id>
   SPACEFAST_TOKEN=<saved-claim-token-or-access-token>
   curl -sS -H "Authorization: Bearer $SPACEFAST_TOKEN" \
     -F "spaceId=$SPACEFAST_SPACE_ID" "${publish_files[@]}" \
     "https://api.spacefast.com/v1/publish?wait=1"

   If an update after claiming returns space_claimed_credential_available, exchange the saved claim token once at POST https://api.spacefast.com/v1/anonymous-claim/exchange, save data.credential.accessToken, and retry with that access token.

Optional shortcuts and reference only: if the sf CLI is already installed, sf publish ./site --wait does the same job. A zip of the publish folder is also supported, but neither the CLI nor a zip is required. Docs: direct agent/API publishing · files and folders · claiming · updates and rollback