"BRB" 是 Usagi Rin 的暂离画面：粉、蓝、淡紫的胖字带白边，写着去拿零食，下面是空的摄像头窗口，旁边一只兔子抱着饼干碗和草莓牛奶。

Create a complete 16:9 kawaii streamer “be right back” screen for Usagi Rin. Render only these exact text strings: “BRB” as the dominant headline; “grabbing snacks!” directly beneath it; “USAGI RIN” as a small screen label. Do not add any other text. Use a bright cream-white background with a faint pink grid-paper pattern and light paper grain. Frame the composition with a large, soft-edged rounded retro computer window, pale pink outline, tiny title bar and three small pastel dot buttons. At the top center of this panel, place “BRB” in chubby hand-drawn letters, each stroke equally plump with fully rounded ends and corners, large round counters, and subtly varied letter heights. Give each letter a matte flat pastel face, a darker outline in its own hue, and one broad white die-cut border wrapping the whole word. Add one small pink heart beside the word. No 3D, gloss, texture, or black outlines; at most one tiny white dot highlight per letter. Set “grabbing snacks!” in a legible, rounded small sans-serif directly below the headline. Leave a large empty rounded camera/avatar window open in the center-left, with a slim info bar beneath it carrying “USAGI RIN”. On the right side, add a cute illustrated snack bowl with crackers and a small juice carton as the scene’s subject, clearly separate from the empty camera window. Scatter a few tiny four-point sparkles, stars, and a ribbon bow near the outer edges; keep the central reading area clear. Use baby pink and sky blue with small lilac accents, soft even daylight, gentle highlight bloom, and only soft shadows. Airy spacing, crisp text, polished streamer overlay, no dark areas, no neon saturation.