body {
  font-family: Arial;
  background: linear-gradient(135deg, #1d2671, #c33764);
  color: white;
  display: flex;
  justify-content: center;
  margin-top: 50px;
  transition: 0.3s;
}

.container {
  width: 360px;
  padding: 20px;
  backdrop-filter: blur(10px);
  background: rgba(255,255,255,0.1);
  border-radius: 15px;
  text-align: center;
  box-shadow: 0 0 20px rgba(0,0,0,0.3);
}

input {
  padding: 10px;
  width: 55%;
  border: none;
  border-radius: 5px;
}

button {
  padding: 8px 10px;
  margin: 5px;
  border: none;
  background: #00adb5;
  color: white;
  border-radius: 5px;
  cursor: pointer;
  transition: 0.3s;
}

button:hover {
  background: #019ca3;
  transform: scale(1.05);
}

li {
  margin-top: 10px;
  list-style: none;
  background: rgba(0,0,0,0.3);
  padding: 10px;
  display: flex;
  justify-content: space-between;
  border-radius: 5px;
  transition: 0.3s;
}

li:hover {
  transform: scale(1.02);
}

li button {
  background: #ff4d4d;
}

li button:hover {
  background: #cc0000;
}

.completed {
  text-decoration: line-through;
  color: lightgray;
  opacity: 0.7;
}

/* Light mode */
.light {
  background: #f4f4f4;
  color: black;
}

.light .container {
  background: white;
  color: black;
}