「Sweet 16」は FontVibe AI で作成したレインボーの文字エフェクトです。鮮やかな多色レインボーグラデーションの文字エフェクトです。滑らかな色の移り変わり、プリズムのような光、そして陽気で色彩豊かなタイポグラフィが特徴です。

rendered as rainbow text effect — COLOR (mandatory): each individual letter must contain a complete ROYGBIV rainbow gradient top-to-bottom within itself — top=red, upper=orange, mid=yellow-green, lower=blue-indigo, bottom=violet. NOT one color per letter. NOT a gradient across the whole word. Every letter is its own complete rainbow. Full chroma Pride flag saturation — not pastel, not muted, not shifted to any single hue. Birthday cake on a dessert table. Top tier has 'Sweet 16' in rainbow balloon letters as an edible printed cake topper — vivid ROYGBIV colors on white fondant. Surrounded by candles, flowers, birthday decorations. Birthday cake using rainbow text as the celebration centerpiece — showing PNG as cake art.