The interlocking-T weave
Tile = triumph-pattern-fog.png (516×688, white-on-transparent, seamless). background-size stays 3:4. Opt-in per panel, never on body.
.brand-field · opacity .08 · tilt -8°
Behind text on navy — subtle.
.brand-field @ .16 (band strength)
Decorative strength.
.brand-field--flat · no tilt · .10
Zero-risk flat fill.
.accent-band · dense · .14
Header / footer strip.
On a light surface
Swap to the navy square tile triumph-pattern-navy.png (square background-size).
.brand-field-light · navy ink · .06