gistfile1.js

function debounce(func, wait, immediate) {
    let timeout;
    return function() {
        let context = this, args = arguments;
        let later = function() {
            timeout = null;
            if (!immediate) func.apply(context, args);
        };
        let callNow = immediate && !timeout;
        clearTimeout(timeout);
        timeout = setTimeout(later, wait);
        if (callNow) func.apply(context, args);
    };
}

const sizeDef = 45,
      sizeMax = 25;

function rowWidth() {
    let getRow = document.querySelector('.edited-row');
        return getRow.offsetWidth;
}

function timelineQuantity() {
     return  parseInt(rowWidth() / sizeMax) - 1;
}

timelineQuantity();

const resizeVal = debounce(function() {
    rowWidth();
    timelineQuantity();
    timeLineList(30);
}, 250);

function timeLineList(quantity) {
    let maxSizeW = quantity * sizeDef;
        if(maxSizeW > rowWidth()) {
            let subtractionW = rowWidth() - maxSizeW,
                shiftElm = Math.abs(subtractionW) / quantity,
                elm = document.getElementsByClassName('edited-box');
                for (let i = 0; i < elm.length; i++) {
                    console.log(elm[i] + ' ' + shiftElm);
                    elm[i + 1].style.marginLeft = -shiftElm + 'px';
                }
        }
}

window.addEventListener('resize', resizeVal);

function rescaleTimelineList(quantity) {
    let maxSizeW      = quantity * sizeDef,
        widthOvershot = maxSizeW - rowWidth();
    if (widthOvershot > 0) {
        let els        = document.getElementsByClassName('edited-box'),
            shiftPerEl = widthOvershot / quantity;
        for (let i = 1; i < els.length; i++) {
            console.log(els[i] + ' ' + shiftPerEl);
            els[i].style.marginLeft = (-shiftPerEl) + 'px';
        }
    }
}