JSFiddle - React, Tailwind, and code Playground

JavaScript

window.minutesPerDay = 60 * 24;

window.pad = function(number) {
    var result = "" + number;
    if (result.length < 2) {
        result = "0" + result;
    }
    
    return result;
};

window.millisToDaysHoursMinutes = function(millis) {
    var seconds = millis / 1000;
    var totalMinutes = seconds / 60;
    
    var days = totalMinutes / minutesPerDay;
    totalMinutes -= minutesPerDay * days;
    var hours = totalMinutes / 60;
    totalMinutes = totalMinutes - hours * 60; 
    
    return days + "." + pad(hours) + "." + pad(totalMinutes);
};

alert(millisToDaysHoursMinutes(minutesPerDay * 3 * 60 * 1000));