* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
}

body {
  background: linear-gradient(135deg, #6a11cb, #2575fc);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: background 0.3s ease;
}


body.dark {
  background: linear-gradient(135deg, #1e293b, #0f172a);
}


.app-container {
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  padding: 25px;
  border-radius: 15px;
  width: 90%;
  max-width: 450px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
  color: white;
  transition: background 0.3s ease, color 0.3s ease;
}

body.dark .app-container {
  background: rgba(0, 0, 0, 0.4);
  color: #e2e8f0;
}

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

h1 {
  font-size: 1.8rem;
}

.theme-btn {
  border: none;
  background: transparent;
  font-size: 1.5rem;
  cursor: pointer;
  color: inherit;
}


.task-input {
  display: flex;
  gap: 10px;
  margin: 15px 0;
}

.task-input input {
  flex: 1;
  padding: 12px;
  border-radius: 8px;
  border: none;
  outline: none;
  font-size: 1rem;
}

.task-input button {
  padding: 12px 18px;
  border: none;
  border-radius: 8px;
  background: #00c6ff;
  color: white;
  font-weight: bold;
  cursor: pointer;
  transition: 0.3s;
}
.task-input button:hover {
  background: #0072ff;
}


.filters {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 15px;
  flex-wrap: wrap;
}

.filters button {
  flex: 1;
  background: rgba(255,255,255,0.2);
  border: none;
  padding: 10px;
  border-radius: 6px;
  color: white;
  cursor: pointer;
  transition: 0.3s;
  font-size: 0.9rem;
}
.filters button.active, .filters button:hover {
  background: #00c6ff;
}


.search-box {
  margin-bottom: 15px;
}
.search-box input {
  width: 100%;
  padding: 10px;
  border-radius: 8px;
  border: none;
  outline: none;
  font-size: 0.95rem;
}


#taskList {
  list-style: none;
  max-height: 300px;
  overflow-y: auto;
}

#taskList li {
  background: rgba(255,255,255,0.1);
  padding: 12px;
  border-radius: 8px;
  margin-bottom: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  animation: fadeIn 0.3s ease-in-out;
  transition: background 0.3s ease;
}

#taskList li.completed {
  text-decoration: line-through;
  opacity: 0.7;
}

.task-actions button {
  border: none;
  background: transparent;
  color: white;
  cursor: pointer;
  margin-left: 8px;
  font-size: 1.1rem;
  transition: transform 0.2s;
}

.task-actions button:hover {
  transform: scale(1.2);
}


.task-stats {
  margin-top: 15px;
  font-size: 0.9rem;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}


@media (max-width: 480px) {
  h1 {
    font-size: 1.5rem;
  }
  .task-input input {
    font-size: 0.9rem;
  }
  .task-input button {
    padding: 10px;
    font-size: 0.9rem;
  }
}