Create an ultra-premium dessert advertising poster for a fictional patisserie "SUCRE DOUX". FORMAT: 4:5 vertical, soft elegant layout. SUBJECT: a delicate lemon-and-elderflower entremet with a white chocolate mirror glaze, edible flowers and a lemon twist, a clean cross-section showing yellow mousse layers. BACKGROUND: soft pale-yellow-to-cream gradient with gentle glow. LIGHTING: soft diffused light, glossy glaze highlights. TYPOGRAPHY: elegant serif logo "SUCRE DOUX" top-center, tiny tagline "Soft sweetness" bottom. FINISH: 8k, hyper-realistic food photography, graceful finish.