PrimaryContentFirst [rule] v1.0.0

The primary task or content must appear first in DOM order and receive the highest visual prominence — supplementary content, sidebars, and ads must come after the main content both structurally and visually.

Severity

medium

PrimaryContentFirst [rule] v1.0.0

The primary task or content must appear first in DOM order and receive the highest visual prominence — supplementary content, sidebars, and ads must come after the main content both structurally and visually.

Severity

medium

Examples

• Correct: main article in DOM before 'Related Articles' sidebar — CSS grid positions them side-by-side
• Violation: navigation sidebar in DOM before
  — screen readers hear nav items before main content
• Correct: use CSS order: -1 on sidebar in grid to visually move it left while DOM order keeps main first
• Violation: hero section after a full-width cookie banner in DOM — banner occupies visual prime estate

Rationale

Screen readers and keyboard users encounter content in DOM order. Search engines weight early DOM content as more important. Mobile single-column layouts collapse CSS side-by-side layouts to DOM order — if the sidebar is first in DOM, it appears first on mobile.

Severity

medium