html, body {
box-sizing: border-box;
}
*, *:before, *:after {
box-sizing: inherit;
}
body {
margin: 0;
padding: 2rem;
font: 16px/1.5 system-ui, sans-serif;
}
h1:first-child {
margin-top: 0;
}
.error {
background: pink;
padding: 1rem;
border-radius: 0.15rem;
}