:root {
  --bg-primary: #1a1a1a;
  --bg-secondary: #2c2c2c;
  --bg-tertiary: #3d3d3d;
  --text-primary: #ffffff;
  --text-secondary: #a0a0a0;
  --accent-primary: #00aaff;
  --accent-secondary: #0077cc;
  --danger: #ff4d4d;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  --radius: 12px;
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Poppins', 'Segoe UI', Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding-top: 4rem;
  min-height: 100vh;
}

.container {
  width: 100%;
  max-width: 550px;
  background-color: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 2.5rem;
  box-shadow: var(--shadow);
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
}

.header h1 {
  font-size: 2.5rem;
  font-weight: 700;
}

.header-right {
  position: relative; /* Crucial for dropdown positioning */
  display: flex;
  align-items: center;
}

.menu-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.menu-btn svg {
  width: 24px;
  height: 24px;
  fill: var(--text-secondary);
  transition: var(--transition);
}

.menu-btn:hover svg {
  fill: var(--text-primary);
}

.menu-dropdown {
  display: none;
  position: absolute;
  right: 0; /* Align to the right of the parent */
  top: 100%; /* Position below the menu button */
  background: var(--bg-tertiary);
  box-shadow: var(--shadow);
  border-radius: 8px;
  min-width: 150px;
  z-index: 10;
  flex-direction: column;
  padding: 0.5rem;
  transform: translateY(0.5rem); /* Small offset from the button */
}

.menu-dropdown .menu-option {
  display: block;
  width: 100%;
  padding: 0.75rem 1rem;
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  font-size: 1rem;
  color: var(--text-primary);
  border-radius: 6px;
  transition: var(--transition);
}

.menu-dropdown .menu-option:hover, .menu-dropdown .menu-option.active {
  background: var(--accent-primary);
  color: var(--text-primary);
}

.task-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2rem;
}

#task-input, #due-date, #subtask-input {
  width: 100%;
  padding: 1rem;
  font-size: 1rem;
  border: 1px solid var(--bg-tertiary);
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  transition: var(--transition);
}

#task-input:focus, #due-date:focus, #subtask-input:focus {
  outline: none;
  border-color: var(--accent-primary);
}

/* Style for date input icon */
#due-date::-webkit-calendar-picker-indicator {
  filter: invert(1); /* Invert color for dark theme */
  cursor: pointer;
}

.subtask-row {
  display: flex;
  flex-direction: column; /* Changed to column to stack input group and buffer */
  gap: 1rem;
}

.subtask-input-group {
  display: flex;
  align-items: center;
  gap: 1rem;
}

#subtask-input {
  flex-grow: 1; /* Allow input to take available space */
}

.add-btn, .add-subtask-btn {
  border: none;
  border-radius: 8px;
  padding: 1rem;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.add-btn {
  background-color: var(--accent-primary);
  color: var(--text-primary);
}

.add-btn:hover {
  background-color: var(--accent-secondary);
}

.add-subtask-btn {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border-radius: 50%; /* Make it circular */
  width: 40px; /* Fixed width for circular button */
  height: 40px; /* Fixed height for circular button */
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 0; /* Remove padding for circular button */
}

.add-subtask-btn svg {
  width: 24px;
  height: 24px;
  fill: var(--text-primary);
}

.add-subtask-btn:hover {
  background-color: var(--accent-primary);
}

.task-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.task-item {
  background-color: var(--bg-tertiary);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: var(--transition);
  position: relative; /* For popup positioning */
}

.task-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.main-task {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.task-checkbox {
  width: 1.2rem;
  height: 1.2rem;
  accent-color: var(--accent-primary);
  border-radius: 4px; /* Ensure square checkboxes */
}

.task-content {
  flex-grow: 1;
}

.task-title {
  font-size: 1.2rem;
  font-weight: 500;
}

.task-due {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

.more-options-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.more-options-btn svg {
  width: 24px;
  height: 24px;
  fill: var(--text-secondary);
  transition: var(--transition);
}

.more-options-btn:hover svg {
  fill: var(--text-primary);
}

.actions-popup {
  position: absolute;
  top: 1.5rem; /* Adjust as needed */
  right: 1.5rem; /* Adjust as needed */
  background-color: var(--bg-secondary);
  border-radius: 8px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  overflow: hidden; /* For animation */
  max-height: 0; /* Initially hidden */
  opacity: 0;
  visibility: hidden;
  transition: max-height 0.3s ease-out, opacity 0.3s ease-out, visibility 0.3s ease-out;
  z-index: 10;
}

.actions-popup.visible {
  max-height: 200px; /* Max height to allow animation */
  opacity: 1;
  visibility: visible;
}

.action-btn {
  background: none;
  border: none;
  padding: 0.75rem 1rem;
  text-align: left;
  color: var(--text-primary);
  font-size: 0.95rem;
  cursor: pointer;
  transition: background-color var(--transition);
}

.action-btn:hover {
  background-color: var(--bg-tertiary);
}

.action-btn.complete-btn {
  color: var(--accent-primary);
}

.action-btn.delete-btn {
  color: var(--danger);
}

#subtasks-buffer-container {
  margin-top: 1rem;
  padding-left: 1rem;
  border-left: 2px solid var(--bg-primary);
}

.subtasks-buffer {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.subtasks-buffer .subtask {
  background-color: var(--bg-secondary);
  padding: 0.75rem 1rem;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.95rem;
}

.subtasks-buffer .subtask span {
  flex-grow: 1;
  word-break: break-word; /* Ensure long words break and wrap */
}

.subtasks-buffer .subtask .subtask-delete-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.2rem;
}

.subtasks-buffer .subtask .subtask-delete-btn svg {
  width: 18px;
  height: 18px;
  fill: var(--text-secondary);
  transition: var(--transition);
}

.subtasks-buffer .subtask .subtask-delete-btn:hover svg {
  fill: var(--danger);
}

.subtasks {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding-left: 1.5rem;
  border-left: 2px solid var(--bg-primary);
}

.subtask {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.subtask-checkbox {
  width: 1rem;
  height: 1rem;
  accent-color: var(--accent-primary);
  border-radius: 4px; /* Ensure square checkboxes */
}

.subtask span {
  flex-grow: 1;
  word-break: break-word; /* Ensure long words break and wrap */
}

.subtask-actions {
  display: flex;
  gap: 0.5rem;
  flex-shrink: 0; /* Prevent actions from shrinking */
}

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.7);
  display: flex;
  justify-content: center;
  align-items: center;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.modal-overlay.visible {
  opacity: 1;
  visibility: visible;
}

.modal-content {
  background-color: var(--bg-secondary);
  padding: 2rem;
  border-radius: var(--radius);
  text-align: center;
}

.modal-actions {
  margin-top: 1.5rem;
  display: flex;
  gap: 1rem;
}

.btn-secondary, .btn-danger {
  padding: 0.8rem 1.5rem;
  border: none;
  border-radius: 8px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.btn-danger {
  background: var(--danger);
  color: var(--text-primary);
}


/* Completed States */
.task-completed .task-title, .subtask-completed span {
  text-decoration: line-through;
  color: var(--text-secondary);
}

/* Edit Input */
.edit-input {
  width: 100%;
  padding: 0.5rem;
  font-size: 1rem;
  border: 1px solid var(--accent-primary);
  border-radius: 6px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}