Strava Challenge Climb Remaining Bookmarklet

strava_climb.js

/* Construct day month year link for Strava Cycling Climbing Challenge */
const d = new Date()
const m = d.toLocaleString('default', {'month':'long'})
const y = d.getFullYear()
const url="https://www.strava.com/challenges/"+m+"-Cycling-Climbing-Challenge-"+y
window.location = url

/* Alert of climb per day remaining */
var arrCalculation = document.querySelectorAll('[class*="ProgressBar--label-"]')
for (a of arrCalculation) {
    for (c of a.classList) {
        if (c.match('right')) {
            var days = Number(a.innerHTML.replace(/[^0-9]/g, ''))
        }
        if (c.match('primary')) {
            var climbed = Number(a.innerHTML.replace(/[^0-9]/g, ''))
        }
        if (c.match('left')) {
            var total = Number(a.innerHTML.replace(/[^0-9]/g, ''))
        }
    }
}
alert(`You need to climb ${(total - climbed)/days} metres a day`)