Calculate circle progress for css gradient values in javascript

circle-progress.js

let step = 1;
let loop = Math.round(100 / step);
let increment = 360 / loop;
let half = Math.round(loop / 2);
let nextDeg = 0;

for (let i = 0; i <= loop; i += step) {
    if (i < half) {
        nextDeg = 90 + increment * i;
        // background-image linear-gradient(90deg, $back-color 50%, transparent 50%, transparent), linear-gradient(nextDeg, $theme-color 50%, $back-color 50%, $back-color)
        console.log('Progress:', i * step, 'First:', 90, 'Second:', nextDeg);
    } else {
        nextDeg = -90 + increment * (i - half);
        // background-image linear-gradient(nextDeg, $theme-color 50%, transparent 50%, transparent), linear-gradient(270deg, $theme-color 50%, $back-color 50%, $back-color)
        console.log('Progress:', i * step, 'First:', nextDeg, 'Second:', 270);
    }
}