[githubflyideas]

• Associate labels with all form controls; add h1/h2, skip link and <main>
• Raise --dim/accent contrast to 4.5:1 and control borders to 3:1 in every theme
• Text alternative for the chart (summary + data table) and a labelled loss axis
• :focus-visible rings, role="alert" on errors, 24px targets, no overflow at 320px