* {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: Arial, sans-serif;
  color: #111;
  background: #fff;
}
main {
  max-width: 640px;
  margin: 12vh auto;
  padding: 24px;
}
h1 {
  font-size: clamp(36px, 7vw, 64px);
}
form,
label {
  display: grid;
  gap: 12px;
}
form {
  max-width: 400px;
}
input,
button {
  font: inherit;
  min-height: 48px;
  padding: 12px;
  border: 1px solid #111;
  border-radius: 0;
}
button {
  background: #ffeb00;
  color: #111;
  font-weight: bold;
  cursor: pointer;
}
button:disabled {
  opacity: 0.6;
}
input:focus-visible,
button:focus-visible {
  outline: 3px solid #111;
  outline-offset: 3px;
}
#error {
  color: #a00000;
}