Circadian Rhythm Reset at Midnight

This chart plots a simplified 24-hour melatonin curve shaped like a real dim-light melatonin onset (DLMO) profile: it rises a couple of hours before your usual bedtime, holds through the night, and falls off toward morning. A light event — brightness, duration, blue-light content and, most importantly, its timing relative to your body's temperature minimum — feeds a genuine phase-response-curve model: light before that minimum delays tomorrow's rhythm, light after it advances instead, with the size of the shift following a real saturating dose-response curve rather than a flat on/off effect. Drag the light-bulb marker onto the timeline to place the exposure, adjust the sliders to see the acute suppression dip and the shifted "tomorrow" curve respond together, and drag or scroll the chart itself to pan and zoom across days.