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

header {
  background: #222;
  color: white;
  padding: 20px;
  text-align: center;
}

main {
  max-width: 1200px;
  margin: 30px auto;
  padding: 0 20px;
}

.calendar-controls {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 25px;
  margin-bottom: 20px;
}

.calendar-controls button {
  font-size: 22px;
  padding: 6px 14px;
  cursor: pointer;
}

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

.day-name,
.day {
  background: white;
  min-height: 120px;
  padding: 8px;
  position: relative;
}

.day-name {
  min-height: auto;
  font-weight: bold;
  text-align: center;
  background: #333;
  color: white;
}

.date-number {
  font-weight: bold;
  margin-bottom: 6px;
}

.other-month {
  background: #eee;
  color: #999;
}

.event {
  background: #2f6fed;
  color: white;
  padding: 4px 6px;
  margin-top: 4px;
  border-radius: 4px;
  font-size: 13px;
  cursor: pointer;
  position: relative;
}

.event-detail {
  display: none;
  position: absolute;
  z-index: 20;
  left: 0;
  top: 24px;
  width: 260px;
  background: white;
  color: #222;
  border: 1px solid #888;
  box-shadow: 0 4px 12px rgba(0,0,0,.25);
  padding: 10px;
  border-radius: 6px;
}

.event:hover .event-detail {
  display: block;
}