diff --git a/.gitignore b/.gitignore
index 5e1d621..94bccfd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,3 +11,6 @@ bench/report.json
 bench/hex-bench/
 bench/hex-bench.zip
 bench/pack/
+
+# Phone bundle: regenerated by scripts/build-phone.mjs
+/build/
diff --git a/scripts/build-phone.mjs b/scripts/build-phone.mjs
new file mode 100644
index 0000000..1fd3357
--- /dev/null
+++ b/scripts/build-phone.mjs
@@ -0,0 +1,113 @@
+#!/usr/bin/env node
+// Build a phone-sized standalone copy of the game carrying one campaign.
+//
+//   node scripts/build-phone.mjs [--campaign=c50] [--out=build/phone]
+//
+// The repository's own static build ships every edition, and v0.5 alone is a
+// 9.2 MB module holding a thousand levels — fine over localhost, not over a
+// phone connection. This swaps the campaign registry for one that names a
+// single edition, then follows the import graph from the entry module, so the
+// editions nobody asked for are never reached and never copied.
+//
+// Two shapes of page, because hosts differ. --standalone emits a complete
+// document for an ordinary static host. The default emits body content only,
+// for Claude Artifacts, whose publisher supplies <!doctype>, <html>, <head> and
+// <body> and rejects a page that brings its own. Either way the stylesheets are
+// inlined rather than linked, so the page has no render-blocking round trips.
+import { copyFileSync, existsSync, mkdirSync, readFileSync, readdirSync, rmSync, writeFileSync } from 'node:fs';
+import { dirname, join, relative, resolve } from 'node:path';
+
+const args = Object.fromEntries(process.argv.slice(2).map(a => { const [k, ...v] = a.replace(/^--/, '').split('='); return [k, v.length ? v.join('=') : true]; }));
+const CAMPAIGN = String(args.campaign ?? 'c50');
+const STANDALONE = Boolean(args.standalone);
+const OUT = resolve(args.out ?? 'build/phone');
+const ROOT = resolve('.');
+
+// The registry, rewritten to one edition. Same exports, so nothing downstream
+// knows the difference.
+const registry = `// Generated by scripts/build-phone.mjs — one edition only.
+import { C50_CAMPAIGN, C50_LEVELS } from './levels-c50.js';
+export const CAMPAIGN_VERSIONS = [{
+  id: C50_CAMPAIGN.id, name: C50_CAMPAIGN.name, description: C50_CAMPAIGN.description,
+  chapters: C50_CAMPAIGN.chapters, chapterSize: C50_CAMPAIGN.chapterSize,
+  levels: C50_LEVELS, legacyStorageKeys: [],
+}];
+export const DEFAULT_CAMPAIGN_VERSION = '${CAMPAIGN}';
+export function campaignVersion(id) {
+  return CAMPAIGN_VERSIONS.find(c => c.id === id) || CAMPAIGN_VERSIONS[0];
+}
+`;
+const OVERRIDES = new Map([[resolve('src/campaign-versions.js'), registry]]);
+
+// Follow every static import from the entry. Dynamic imports are not followed;
+// the game has none, and a miss would show up as a 404 rather than silently.
+const IMPORT = /(?:^|\n)\s*(?:import|export)\s[^'"]*from\s*['"]([^'"]+)['"]|(?:^|\n)\s*import\s*['"]([^'"]+)['"]/g;
+const seen = new Map();
+function walk(file) {
+  if (seen.has(file)) return;
+  const source = OVERRIDES.get(file) ?? readFileSync(file, 'utf8');
+  seen.set(file, source);
+  for (const m of source.matchAll(IMPORT)) {
+    const spec = m[1] ?? m[2];
+    if (!spec.startsWith('.')) continue;             // bare specifiers: none in this project
+    walk(resolve(dirname(file), spec));
+  }
+}
+walk(resolve('src/app.js'));
+
+// One <style> block, in the order index.html linked them.
+const html = readFileSync(resolve('index.html'), 'utf8');
+const sheets = [...html.matchAll(/<link rel="stylesheet" href="([^"]+)"/g)].map(m => m[1]);
+const css = sheets.map(href => `/* ${href} */\n${readFileSync(resolve(href), 'utf8')}`).join('\n');
+
+// Stylesheets under design/ reach the art with ../assets/; inlined into a page
+// at the root, that path climbs out of the bundle. Rewrite before collecting,
+// so what is collected is what the page will actually ask for.
+const cssFixed = css.replace(/\.\.\/assets\//g, 'assets/');
+
+// Art is referenced from code and from stylesheets, never from index.html, so
+// the import graph cannot find it. Both sources are scanned, and anything named
+// but missing is reported rather than shipped as a broken image — a missing
+// tile sheet degrades to the fallback renderer and looks like a design choice.
+const assets = new Set();
+for (const source of [...seen.values(), cssFixed]) {
+  for (const m of source.matchAll(/assets\/[A-Za-z0-9_.\/-]+\.(?:png|webp|jpg|svg|woff2?)/g)) assets.add(m[0]);
+}
+const missing = [...assets].filter(a => !existsSync(resolve(a)));
+if (missing.length) { console.error(`引用了但找不到：${missing.join(' ')}`); process.exit(1); }
+
+const title = (html.match(/<title>([^<]*)<\/title>/) ?? [, 'HEX TRAILS'])[1];
+const body = html
+  .replace(/^[\s\S]*?<body>/, '')
+  .replace(/<\/body>\s*<\/html>\s*$/, '')
+  .trim();
+
+rmSync(OUT, { recursive: true, force: true });
+mkdirSync(OUT, { recursive: true });
+const head = `<title>${title}</title>\n<style>\n${cssFixed}\n</style>`;
+// viewport-fit=cover lets the board sit under a phone's notch; the Artifact
+// skeleton supplies its own viewport meta, so only the standalone page needs it.
+writeFileSync(join(OUT, 'index.html'), STANDALONE
+  ? `<!doctype html>\n<html lang="zh-CN">\n<head>\n<meta charset="utf-8">\n`
+    + `<meta name="viewport" content="width=device-width,initial-scale=1,viewport-fit=cover">\n`
+    + `<meta name="theme-color" content="#A8BECF">\n${head}\n</head>\n<body>\n${body}\n</body>\n</html>\n`
+  : `${head}\n${body}\n`);
+for (const asset of assets) {
+  mkdirSync(join(OUT, dirname(asset)), { recursive: true });
+  copyFileSync(resolve(asset), join(OUT, asset));
+}
+for (const [file, source] of seen) {
+  const rel = relative(ROOT, file);
+  mkdirSync(join(OUT, dirname(rel)), { recursive: true });
+  writeFileSync(join(OUT, rel), source);
+}
+
+const size = dir => readdirSync(dir, { withFileTypes: true })
+  .reduce((n, e) => n + (e.isDirectory() ? size(join(dir, e.name)) : readFileSync(join(dir, e.name)).length), 0);
+const kb = n => (n / 1024).toFixed(0) + ' KB';
+console.log(`入口 src/app.js → ${seen.size} 个模块`);
+console.log(`样式 ${sheets.length} 个文件已内联（${kb(cssFixed.length)}）`);
+console.log(`资源 ${assets.size} 个：${[...assets].map(a => `${a.replace('assets/', '')} ${kb(readFileSync(resolve(a)).length)}`).join(' · ')}`);
+console.log(`产物 ${OUT}：${kb(size(OUT))}（${STANDALONE ? '完整 HTML 文档，适合普通静态托管' : '仅 body 内容，适合 Claude Artifact'}）`);
+const heavy = [...seen].map(([f, s]) => [relative(ROOT, f), s.length]).sort((a, b) => b[1] - a[1]).slice(0, 3);
+console.log(`最大的模块 ${heavy.map(([f, n]) => `${f} ${kb(n)}`).join(' · ')}`);