--- title: "Theme" description: "Select a Deckup theme, compare built-in themes, and resolve installed or registry packages." --- > Documentation Index > Fetch the complete documentation index at: https://deckup.yuku.dev/llms.txt > Use this file to discover all available pages before exploring further. # Theme Themes provide Astro layout components for Deckup pages. Select a fallback in `deckup.config.*`: ```ts import { defineConfig } from "deckup"; export default defineConfig({ theme: "google-basic", }); ``` Deck-level static metadata overrides the configured fallback. If neither is present, Deckup uses `default`. ## Built-in themes - **Default** — Default theme cover with a serif heading and circular ornament Open interactive deck →

Serif headings, cool blue accents, and geometric details.

- **Minimal** — Minimal theme cover with a monochrome centered heading Open interactive deck →

Monochrome styling with a clear, document-like hierarchy.

- **Google Basic** — Google Basic theme cover with white type on a blue background Open interactive deck →

Bright blue surfaces with a clear structural hierarchy.

- **Apple Basic** — Apple Basic theme cover with large black type on white Open interactive deck →

High-contrast composition led by large, confident typography.

Each interactive deck demonstrates the seven layouts shared by the built-in themes. ## Installed package themes Install a third-party package in the deck project and use its package specifier: ```ts export default defineConfig({ theme: "@acme/deckup-theme", }); ``` ## Registry themes Use `npm:` to let Deckup resolve a package before Astro starts: ```ts export default defineConfig({ theme: "npm:@acme/deckup-theme@1.2.3", }); ``` Both `npm:package` and exact `npm:package@version` specs are supported. Deckup caches downloaded packages; set `DECKUP_THEME_CACHE_DIR` to choose another cache directory. An uncached download requires confirmation, and non-interactive runs stop with guidance instead of downloading automatically. Deckup does not automatically replace an invalid cache entry. If a cached theme fails validation (for example, edited or corrupted metadata or package files), Deckup reports the error instead of deleting and re-downloading it. To recover, verify no Deckup process is using that cache entry, remove only the named entry under the cache directory's `packages/` folder, then rerun Deckup interactively to re-download it. Avoid deleting the whole cache directory; that removes every other theme you already have cached. Deckup serializes concurrent downloads of the same theme with a per-package cache lock. Acquiring that lock waits up to 60 seconds; if the wait times out, Deckup reports a timeout error naming the theme, the wait duration, and the lock directory instead of waiting indefinitely. A lock only remains past that window if a Deckup process abandoned it (for example, a crash or a killed process). To recover, confirm no Deckup process is using that theme, then remove the named `.lock` directory under the cache directory's `locks/` folder before retrying. Do not remove a lock while a Deckup process still holds it. To create a reusable package, read [Authoring Themes](/guides/authoring-themes/). Source: https://deckup.yuku.dev/references/theme/index.mdx