body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  background-color: #f4f4f4;
  color: #333;
}

body.light { background: #f4f4f4; color: #333; }
body.dark { background: #181818; color: #eee; }
body.blue { background: #e3f0ff; color: #222; }

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background-color: #24292e;
  color: white;
  padding: 1rem 2rem;
}

nav h1 {
  margin: 0;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 1rem;
}

nav ul li {
  cursor: pointer;
  padding: 0.5rem 1rem;
  border-radius: 5px;
}

nav ul li:hover {
  background-color: #444c56;
}

main {
  padding: 2rem;
}

section {
  display: none;
}

section.active {
  display: block;
}

.task-input {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.task-input input {
  flex: 1;
  padding: 0.75rem;
  font-size: 1rem;
}

.task-input button {
  padding: 0.75rem 1.5rem;
  background-color: #007acc;
  color: white;
  border: none;
  cursor: pointer;
  border-radius: 4px;
}

#taskList {
  list-style: none;
  padding: 0;
  max-width: 700px;
}

#taskList li {
  background-color: white;
  padding: 1rem;
  margin-bottom: 0.5rem;
  border-radius: 6px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

#calendarTasks {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.calendar-day {
  background-color: #fff;
  padding: 1rem;
  border-radius: 6px;
  box-shadow: 0 0 4px rgba(0, 0, 0, 0.1);
}

.calendar-day h3 {
  margin-top: 0;
}

.edit-btn {
  margin-left: 8px;
  background: #ffd966;
  border: none;
  padding: 4px 8px;
  cursor: pointer;
  border-radius: 3px;
}

.edit-input {
  width: 60%;
  padding: 2px 4px;
}

.deadline {
  color: #888;
  font-size: 0.95em;
  margin-left: 8px;
}

.category {
  background: #e0e7ff;
  color: #2c3e50;
  font-size: 0.95em;
  padding: 2px 8px;
  border-radius: 12px;
  margin-left: 8px;
  margin-right: 8px;
}

.priority {
  font-weight: bold;
  padding: 2px 8px;
  border-radius: 12px;
  margin-left: 8px;
  margin-right: 8px;
}

.priority.high {
  background: #ffcccc;
  color: #b30000;
}

.priority.medium {
  background: #fff3cd;
  color: #856404;
}

.priority.low {
  background: #d4edda;
  color: #155724;
}

.completed .task-text {
  text-decoration: line-through;
  color: #aaa;
}

.dragElem {
  opacity: 0.4;
}