body {
  font-family: sans-serif;
  background-color: #e6f2ff;
  padding: 20px;
  margin: 0;
}

h1 {
  text-align: left;
  margin-bottom: 20px;
  font-size: 24px;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 15px;
}

.controls button,
.controls select,
.controls input[type="file"] {
  padding: 8px 12px;
  font-size: 14px;
}

#calendar {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 8px;
  max-width: 700px;
  min-height: 300px;
}

.day {
  background: #fff;
  border: 1px solid #ccc;
  padding: 10px;
  text-align: center;
  white-space: pre-line;
  font-size: 14px;
  border-radius: 4px;
}

.day.empty {
  background-color: transparent;
  border: none;
}

.today {
  background: #ffeeba;
  border-color: #f0ad4e;
}

.marked {
  background: #d4edda;
  border-color: #28a745;
}

.day:hover {
  background-color: #f0f8ff;
  cursor: pointer;
}