body { font-family: system-ui, sans-serif; max-width: 780px; margin: 2rem auto; padding: 0 1rem; }
nav button.active { font-weight: bold; }
.tab { display: none; }
.tab.active { display: block; }
.q { margin: 1rem 0; }
.q label { display: block; }
input, textarea, button { padding: .4rem; margin: .25rem 0; }
textarea { width: 100%; min-height: 60px; }
#review-msg.ok { color: green; }
#review-msg.err { color: crimson; }