科普图表：一夜安眠图谱

Scientific infographic poster explaining human sleep cycles and brain-wave stages, front-view flat presentation. Layout: a large circular cycle diagram at the center showing one 90-minute sleep cycle divided into four colored segments: stage N1 light sleep, stage N2, stage N3 deep slow-wave sleep, and REM sleep, with small flat icons for the drowsy face, heart monitor, moon and dreaming cloud. A horizontal line chart beneath the circle plots a full night of 7-8 hours across five to six consecutive cycles, showing how deep sleep dominates early hours and REM episodes lengthen toward morning, with annotated brain-wave waveform strips for alpha, theta, delta and beta rhythms. Color system: calming indigo (#312E81), soft lavender (#A78BFA), dusk blue (#60A5FA) and warm peach (#FBBF24) for the REM accent on a pale night-sky background (#F5F3FF). Typography: rounded sans-serif title, clear stage labels, thin waveform captions. Background: subtle star-specks and soft moonlit gradient. Data feel: sleep-lab clinical chart with time axis and stage banding. Lighting: soft ambient night glow, gentle shadows, luminous accents. 4k