html, body { margin: 0; }
body {
  background: #d9e3ea;
  color: #14202a;
  font: 16px/1.4 "Segoe UI", Tahoma, sans-serif;
}
main { max-width: 48rem; margin: 0 auto; padding: 4rem 1rem; }
h1 { font-weight: 600; margin: 0 0 2rem; }
.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
@media (max-width: 700px) { .grid { grid-template-columns: 1fr; } }
section {
  background: #f4f7f9;
  border-radius: 12px;
  padding: 1rem 1rem 1.4rem;
}
select {
  font: inherit;
  width: 100%;
  border: 0;
  background: transparent;
  margin-bottom: 0.6rem;
}
.clock {
  font-size: 2.6rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.03em;
}