Can someone explain why - in this instance - an input tag would exceed the width of it's parent? If you inspect the element it's got nothing to do with the padding, border or margins...
* {
box-sizing: border-box;
}
.foo {
width: 400px;
}
.bar {
font-size: 40px;
}
<div class="foo">
<input type="number" class="bar" />
</div>