I don't see this button either (desktop) but searching the HTML gives a <script> that says

  window.__LEVEL__ = null; window.__DAILY_MODE__ = true; window.__DAILY_LEVELS__ = [{"id":"FswXDo","date":"2026-01-06","dayNumber":8,"optimalScore":86},{"id":"6UV4Yw","date":"2026-01-05","dayNumber":7,"optimalScore":95},{"id":"VfWi_1","date":"2026-01-04","dayNumber":6,"optimalScore":77},{"id":"CNtGPI","date":"2026-01-03","dayNumber":5,"optimalScore":116},{"id":"tnLvlG","date":"2026-01-02","dayNumber":4,"optimalScore":51},{"id":"Qn9vLs","date":"2026-01-01","dayNumber":3,"optimalScore":74},{"id":"Kj7mXp","date":"2025-12-31","dayNumber":2,"optimalScore":90},{"id":"E03KkY","date":"2025-12-30","dayNumber":1,"optimalScore":68}];

Results, then scroll down a tiny bit.