Redesign site as a coherent editorial/product system

[dkharlanau]

Goal

Turn the public site into one coherent editorial/product experience: easier to read, easier to browse, visually quieter, and ready for continued learning, Atlas, services and product work.

Audit and design-system outcome

• add a final shared assets/editorial-system.css layer so specialist route styles no longer redefine the reading contract
• move long-form reading to a roughly 44rem measure with Source Serif 4, 18–20px-class copy, ~1.7 line-height and restrained heading scale
• reduce headline weight, card chrome, shadows and unnecessary visual variation
• align homepage, hubs, services, Atlas/long-form content, learning surfaces and responsive layouts around the same spacing/color rules
• use blue for routes/actions/evidence and red for tension/risk/diagnostic boundaries
• keep existing URLs, content architecture and publication controls intact

Representative redesigns

• homepage two-path focus (Learn / prepare and Improve SAP / AMS)
• Atlas diagnostic reading experience
• long-form article typography, tables, code, callouts and captions
• hub/category route layouts
• services problem → evidence → action flow
• responsive tablet/mobile treatment

Image system

• add analytical evidence matrices to:
  • /atlas/diagnostics/sap-incident-triage-diagnostics/
  • /atlas/diagnostics/sap-master-data-diagnostics-hub/
• provide desktop 3:2 and mobile 2:3 WebP variants
• prevent duplicate generic reader visuals when a dedicated analytical figure exists
• reserve responsive image geometry to reduce layout shift
• standardize registry attribution as Author: Dzmitryi Kharlanau
• expose attribution through quiet ImageObject metadata instead of repeating visible credit labels
• keep generation provenance separately in _data/article_visuals.yml

Maintainer documentation

• docs/editorial-design-system.md — audit, tokens, page-type contracts, responsive/accessibility/performance rules
• docs/editorial-image-strategy.md — page-type image policy, red/blue semantics, current manifest, art-direction template and delivery rules

Visual-smoke reliability

The prior CI failure was traced to the smoke detector treating controls inside closed native <details> elements as visible. Screenshots showed those controls were not painted. The detector now excludes descendants hidden by a closed disclosure while still testing its visible <summary>.

Safety boundaries

• no Atlas verification status changed
• no robots/indexing status changed
• no sitemap/publication boundary changed
• no private corpus content added
• no URLs intentionally changed
• no heavy styling framework introduced

Verification

Earlier branch state already passed public-repo hygiene, source heading hierarchy, deterministic-state generation, Python tests, Career Factory checks, Jekyll build and rendered-Markdown checks. Its visual-smoke run exposed the closed-details false positives described above.

Final CI and Knowledge Publication Contract are being rerun on the latest head and are authoritative before merge.