:root { font-family: system-ui, sans-serif; }
body { margin: 0; }
nav { display: flex; gap: 1rem; align-items: center; padding: 0.5rem 1rem; border-bottom: 1px solid #ddd; }
nav form { margin-left: auto; }
main { max-width: 60rem; margin: 1rem auto; padding: 0 1rem; }
label { display: block; margin: 0.5rem 0; }
.error { color: #b00020; }