Fit text to a container width
function fitText() {
var numberContainer = document.querySelector('.number-container');
var blockCounter = document.querySelector('.block-counter');
var number = document.querySelector('.number');
var fontSize = 200;
var containerWidth = blockCounter.offsetWidth - 20;
var numberWidth = number.offsetWidth;
var scale = containerWidth / numberWidth;
fontSize = Math.floor(fontSize * scale);
numberContainer.style.fontSize = fontSize + 'px';
}
window.addEventListener('load', fitText);
window.addEventListener('resize', fitText);