JSFiddle - React, Tailwind, and code Playground
JavaScript
function closest(arr, closestTo){
var closest = Math.max.apply(null, arr);
for(var i = 0; i < arr.length; i++){
if(arr[i] >= closestTo && arr[i] < closest) closest = arr[i];
}
return closest;
}
alert(closest([300, 500, 700, 1000, 2000, 3000], 1200))