A schematic cross-section diagram of sleep onset stages displayed on a modern laboratory monitor screen, highlighting the precise transition window where brief muscle contraction occurs.. Spatial layout: График мозговой активности и мышечного тонуса развернут по горизонтальной шкале времени перехода ко сну.. Context markers: laboratory cognitive testing equipment, sleep stage timeline graph. The complete visual composition—including all primary subjects, secondary supporting elements, boundaries, and environmental contours—must sit comfortably inside the canvas with generous clean white negative space visible on all four sides (target 8-12% margins, minimum 6%). The entire visual assembly must occupy maximum 80% canvas height and 84% canvas width. Nothing touches or crosses any canvas edge. Do not crop the primary subject. Clean isolated 2D explainer composition against pure white/off-white background. hand-drawn 2D explainer cartoon illustration, confident clean black outlines, flat cel-style colors, simplified readable forms, soft minimal shading, clear focal hierarchy, clean educational YouTube illustration, no photorealism, no 3D rendering, no typography, no text, no watermarks
