JavaScript (padding.js)
javascript
document.getElementById('numberInput').addEventListener('input', function(event) {
var input = event.target;
var value = input.value;
// Remove non-digit characters
input.value = value.replace(/\D/g, '');
});
document.getElementById('numberInput').addEventListener('blur', function(event) {
var input = event.target;
var value = input.value;
if (value.length < 6) {
input.value = value.padStart(6, '0');
}
});