body {
  font-family: system-ui, sans-serif;
  background: #f4f4f6;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
}

.card {
  background: #fff;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  max-width: 400px;
  width: 100%;
}

.calendar {
  margin-top: 1.25rem;
}

.calendar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
  font-weight: 600;
}

.calendar-header button {
  background: none;
  border: none;
  color: #2d6cdf;
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  padding: 0.25rem 0.6rem;
  border-radius: 4px;
}

.calendar-header button:hover {
  background: #eef2fc;
}

.calendar-weekdays {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  text-align: center;
  font-size: 0.8rem;
  color: #888;
  margin-bottom: 0.25rem;
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 4px;
}

.day {
  aspect-ratio: 1 / 1;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
  background: #f4f4f6;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.9rem;
}

.day:hover {
  background: #d9e4fb;
}

.day.filler {
  background: transparent;
  cursor: default;
}

.day.today {
  background: #2d6cdf;
  color: #fff;
  font-weight: 600;
}