* {
  box-sizing: border-box;
  font-family: Arial, sans-serif;
}

body {
  background: #f4f4f4;
  display: flex;
  justify-content: center;
  padding-top: 50px;
  transition: background 0.3s;
}

body.dark {
  background: #1e1e1e;
  color: white;
}

.app {
  background: white;
  padding: 20px;
  width: 320px;
  border-radius: 8px;
}

body.dark .app {
  background: #2c2c2c;
}

h1 {
  text-align: center;
}

#dark-toggle {
  width: 100%;
  margin-bottom: 10px;
  padding: 6px;
  cursor: pointer;
}

form {
  display: flex;
  gap: 5px;
  margin-top: 10px;
}

input {
  flex: 1;
  padding: 8px;
}

button {
  padding: 8px;
  cursor: pointer;
}

.filters {
  display: flex;
  justify-content: space-between;
  margin-top: 10px;
}

.filter-btn {
  flex: 1;
  margin: 0 3px;
  padding: 6px;
  border: none;
  background: #eee;
}

.filter-btn.active {
  background: #ffd966;
  font-weight: bold;
}

ul {
  list-style: none;
  padding: 0;
  margin-top: 20px;
}

li {
  background: #fff9a6;
  padding: 12px;
  margin-bottom: 12px;
  border-radius: 6px;

  display: flex;
  justify-content: space-between;
  align-items: center;

  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
  transform: rotate(-1deg);
  transition: transform 0.2s, box-shadow 0.2s;
}

li:nth-child(even) {
  transform: rotate(1deg);
}

li:hover {
  transform: scale(1.03) rotate(0deg);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.25);
}

.completed {
  text-decoration: line-through;
  opacity: 0.6;
}

body.dark li {
  background: #444;
}