fix: mermaid light-mode + add About page (Variation B)

.github/workflows/ci.yml

@@ -1,5 +1,9 @@
 name: CI
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
 on:
   pull_request:
     branches: [main]

.github/workflows/deploy.yml

@@ -1,5 +1,17 @@
 name: Deploy
 
+# Release variant — never cancel a deploy mid-flight. A cancelled deploy
+# can leave the Netcup site in a half-deleted state (the script does
+# `find . -delete && tar -xzf`). Group by ref so two parallel pushes to
+# the same branch serialize cleanly without race-deleting each other.
+#
+# Security note: this concurrency block uses only server-controlled
+# context vars (github.ref, github.workflow) — no PR-author-controlled
+# input flows into the group key.
+concurrency:
+  group: release-${{ github.ref }}
+  cancel-in-progress: false
+
 on:
   push:
     branches: [main]

content/about.md

@@ -0,0 +1,5 @@
++++
+title = "About"
+description = "Open source. Pre-1.0. Each tool tests a thesis about AI-velocity verification for safety-critical software. Here's the bench, here's what it produced, here's what we don't yet know."
+template = "about.html"
++++

sass/_blog.scss

@@ -236,6 +236,24 @@
     }
   }
 
+}
+
+// Mermaid light-mode color override is handled in JS, not CSS.
+//
+// Why: each post's `classDef` lines compile to CSS rules INSIDE the
+// rendered SVG's `<style>` tag, scoped by a dynamic id (`#mermaid-NNN`)
+// and marked `!important`. That combination of (ID selector +
+// !important + later source order than main.css) means outer CSS
+// cannot override them, regardless of attribute / class selectors or
+// added !importants.
+//
+// The fix lives in `templates/blog-page.html`: after mermaid renders,
+// the script walks each `.mermaid svg style` element and rewrites the
+// hardcoded dark hex values to their cream-mode equivalents. See the
+// `applyMermaidLightFix` function there.
+
+.blog-post__content {
+
   // Tables
   table {
     width: 100%;