A blog on the vibe preset follows the reader's OpenVibe theme (the official blog's front page pinned vibe's blue over the season's colours) (#91)

ddiff --git a/server/domain/blogs.js b/server/domain/blogs.js
iindex 184ba38..f0a21d2 100644
---- a/server/domain/blogs.js
++++ b/server/domain/blogs.js
@@@ -125,8 +125,15 @@ function createBlogs({ store, config }) {
              return await q.byId.get(blog.id);
          },
  
--        /** CSS custom properties of the blog's preset, for its content surface. */
--        themeVars(blog) { return (THEMES[blog.theme] || THEMES.vibe).variables; },
++        /**
++         * CSS custom properties of the blog's preset, for its content surface. `vibe` is the network's own default: a
++         * blog that keeps it follows whatever theme the reader has on OpenVibe (a season's colours included) instead of
++         * pinning vibe's values, so the official blog's front page matches every other site.
++         */
++        themeVars(blog) {
++            if (!THEMES[blog.theme] || blog.theme === 'vibe') return {};
++            return THEMES[blog.theme].variables;
++        },
  
          async feedSettings(blog) { return await q.feed.get(blog.id) || { blog_id: blog.id, rss: 1, atom: 1, json: 1, item_count: 20, full_content: 1 }; },
  
ddiff --git a/server/render/layout.js b/server/render/layout.js
iindex 4949829..4f3775a 100644
---- a/server/render/layout.js
++++ b/server/render/layout.js
@@@ -71,7 +71,8 @@ function renderPage(o) {
          notificationsRealtime: true,             // the bell hears new notifications over OpenVibe.Events (Shared 1.22.0)
      };
      const footer = { service: 'blog', variant: 'full', mount: '#ov-footer', brandName: SITE_NAME, updates: '/updates' };
--    const style = o.theme ? ` style="${esc(themeStyle(o.theme.vars))}" data-blog-theme="${esc(o.theme.slug)}"` : '';
++    const vars = o.theme ? themeStyle(o.theme.vars) : '';
++    const style = o.theme ? `${vars ? ` style="${esc(vars)}"` : ''} data-blog-theme="${esc(o.theme.slug)}"` : '';
      const account = signedIn
          ? `<a href="/write">Write</a> · <a href="/auth/logout?next=${loginNext}">Sign out</a>`
          : `<a href="/auth/login?next=${loginNext}">Sign in with OpenVibe</a>`;
ddiff --git a/test/layout.test.js b/test/layout.test.js
iindex b6f9c79..aedbcdb 100644
---- a/test/layout.test.js
++++ b/test/layout.test.js
@@@ -54,6 +54,10 @@ const split = (html) => ({ head: html.slice(0, html.indexOf('</head>')), body: h
          assert.ok(body.includes('OpenVibeFooter.init(window.__OV_PAGE.footer)'), 'the footer is initialised');
          assert.ok(/<main id="main" class="page blog-surface" style="--[^"]+" data-blog-theme="paper">/.test(body), 'the theme preset stays on the content surface');
          assert.strictEqual(count(r.text, /<main\b/g), 1, 'one <main>');
++        // vibe is the network's default: a blog on it follows the reader's OpenVibe theme, so no colours are pinned.
++        const { renderPage } = require('../server/render/layout');
++        const vibe = renderPage({ decision: { robots: 'index, follow' }, config: { baseUrl: 'https://openvibe.blog' }, body: 'x', theme: { slug: 'vibe', vars: {} } });
++        assert.ok(vibe.includes('<main id="main" class="page blog-surface" data-blog-theme="vibe">'), 'vibe pins no colours');
      });
  
      await check('the editor stays noindex; the home page keeps its feeds, the Blog JSON-LD and the AI summary', async () => {
ddiff --git a/test/theme-presets.test.js b/test/theme-presets.test.js
nnew file mode 100644
iindex 0000000..1ec4c02
---- /dev/null
++++ b/test/theme-presets.test.js
@@@ -0,0 +1,20 @@
++'use strict';
++/**
++ * Blog theme presets on the content surface: `vibe`, the network's own default, pins no colours (a blog on it
++ * follows the reader's OpenVibe theme, a season's colours included: the official blog's front page was the one
++ * blue page among the network's homes in the 2026-10-27 visual pass); a preset a blog chose keeps its values.
++ */
++const assert = require('assert');
++const { createBlogs, THEME_PRESETS } = require('../server/domain/blogs');
++
++const stub = { prepare: () => ({ get: () => null, all: () => [], run: () => ({}) }) };
++const blogs = createBlogs({ store: { db: stub }, config: {} });
++
++assert.deepStrictEqual(blogs.themeVars({ theme: 'vibe' }), {}, 'vibe follows the network theme');
++assert.deepStrictEqual(blogs.themeVars({ theme: null }), {}, 'no preset: the network theme');
++assert.deepStrictEqual(blogs.themeVars({ theme: 'no-such-theme' }), {}, 'an unknown preset: the network theme');
++for (const preset of THEME_PRESETS.filter((p) => p !== 'vibe')) {
++    const vars = blogs.themeVars({ theme: preset });
++    assert.ok(vars['--bg-primary'] && vars['--accent'], `${preset} keeps its own colours`);
++}
++console.log('theme presets: all checks passed');