Add menu link size, spacing, a current-page mark and a spread alignment

Size and spacing selects, a choice of how the current page's link is
marked (underlined as before, bold, boxed or not at all) and a fourth
alignment that spreads the header's links across the bar. Alignment
joins the other menu classes on the body, so the theme CSS no longer
sets it; spread is justified text with a full-width last line, which
old browsers lay out too, and stays out of the column menus.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Sd8UPWrvyYCLj97JexNw3A

1 files changed, 3 insertions, 1 deletions

diff --git a/README.md b/README.md
index 27919ef..ebb1a4d 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,9 @@ Server-rendered HTML, no JavaScript required, works on old browsers and phones.
   stack under the posts; the header and footer can follow the main column's edges
   for a centred, single-column look, and a rule (line, dots or stripes) can fill the
   row beside the title or logo. The **menu** mixes blog pages and outside links; its
-  links can be bold, uppercase, underlined always, on hover or never, in any combination. Posts per
+  links can be bold, uppercase, underlined always, on hover or never, small or large,
+  tight or wide apart, in any combination; the current page's link is underlined, bold,
+  boxed or left alone, and the header menu sits left, centred, right or spread across the bar. Posts per
   page, the date format, the site title size and the footer alignment live here too,
   as does whether listings show whole posts or **summaries** with a "Read more" link
   (a post's summary ends at a `<!--more-->` line, or after its first paragraphs).