# Free shipping threshold hidden — dev spec
Site: allbirds.com · Priority 4 · High · Effort: Medium (2-5 days)

## Problem
The homepage hero promotes 'Wildly Comfortable. Super Natural.' but the free shipping threshold ($100) is only disclosed in the sitewide banner, creating an expectation of free shipping that may not apply to all orders.

## Evidence (from the live site)
> Homepage body_sample: 'Free ground shipping on orders over $100' appears in the top banner, but the hero copy 'Wildly Comfortable. Super Natural.' and CTAs 'SHOP MEN' / 'SHOP WOMEN' do not mention any shipping threshold. The cart drawer shows 'Spend more to earn free shipping! Shipping $5.00' when subtotal is below $100.

## Current state
h1: Wildly Comfortable. Super Natural.; cta: SHOP MEN / SHOP WOMEN; notes: Free shipping threshold only in banner, not in hero or product pages.

## Required change
h1: Wildly Comfortable. Super Natural. Free Shipping Over $100.; cta: SHOP MEN / SHOP WOMEN; notes: Add free shipping threshold to hero or primary CTAs to set expectations early.

## Acceptance criteria
- GIVEN a first-time visitor on the affected page
- WHEN the change is live
- THEN Add free shipping threshold to hero or primary CTAs to set expectations early.
- AND no layout regression at 375px / 768px / 1280px
- AND the changed control is keyboard-reachable with an accessible name

## Tracking
- Fire `cro_free_shipping_threshold_hidden` on interaction with the changed element
- Verify the event fires in BOTH variants before opening traffic

## Test plan
- Two-proportion z-test, 95% significance, 80% power
- 299,882 visitors per variant to detect a 5.0% relative lift
- Run at least one full business cycle; not testable at current traffic

## Rollback
Feature-flag the change; revert if the primary metric drops for 3 consecutive days.