body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: #f5f5f5;
}

header {
  background-color: #317EFB;
  color: white;
  padding: 1em;
}

nav button {
  margin: 0 5px;
  padding: 0.5em 1em;
}

main {
  padding: 1em;
}

section.hidden {
  display: none;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1em;
  max-width: 400px;
}

.error {
  color: red;
}
.info {
  color: green;
}

#calendarContainer {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 1px;
  background: #ccc;
}

.day-column {
  background: white;
  min-height: 400px;
  padding: 0.5em;
  border: 1px solid #ccc;
}

.booking {
  background: #90caf9;
  margin: 4px 0;
  padding: 4px;
  border-left: 4px solid #1976d2;
}