Sleep Low - check a high-altitude trek's pace, night by night

A pace check for high-altitude trek itineraries. Paste one night a line - place, sleeping altitude, highest point that day - with where you start: the page draws the ascent as a contour map (each ring 500 m), flags every night that climbs more than 500 m above 3,000 m, every fourth climbing night in a row and a fly-in start at 3,500 m or more, and builds the fewest extra nights that fix it, free in the browser. A metered pace check adds the nights where they fit the route, names warning signs for the highest nights, sets turnaround rules and lists questions for the guide, with an on pace / add nights / rethink verdict; the page re-walks every change. General pacing guidance, not medical advice. Built on @travisjneuman/travel-planner.