/* Catppuccin Latte (Light Theme - Default) */
:root {
  --bg-primary: #eff1f5;
  --bg-secondary: #e6e9ef;
  --bg-elevated: #ccd0da;
  --text-primary: #4c4f69;
  --text-secondary: #6c6f85;
  --accent: #1e66f5;
  --accent-hover: #04a5e5;
  --border: #acb0be;
  --danger: #d20f39;
  --danger-hover: #e64553;
  --success: #40a02b;
  --shadow: rgba(76, 79, 105, 0.15);
}

/* Catppuccin Mocha (Dark Theme - Auto based on system preference) */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-primary: #1e1e2e;
    --bg-secondary: #181825;
    --bg-elevated: #313244;
    --text-primary: #cdd6f4;
    --text-secondary: #bac2de;
    --accent: #89b4fa;
    --accent-hover: #74c7ec;
    --border: #45475a;
    --danger: #f38ba8;
    --danger-hover: #eba0ac;
    --success: #a6e3a1;
    --shadow: rgba(0, 0, 0, 0.4);
  }
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  transition: background 0.2s ease, color 0.2s ease;
}

header {
  padding: 1rem;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 4px var(--shadow);
  position: sticky;
  top: 0;
  z-index: 10;
}

header h1 {
  font-size: 1.25rem;
  font-weight: 600;
}

main {
  max-width: 600px;
  margin: 0 auto;
  padding: 1rem;
}

.screen {
  animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* List Screen */
.list-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  gap: 0.5rem;
}

.sort-toggle {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 0.5rem 0.75rem;
  border-radius: 0.375rem;
  cursor: pointer;
  font-size: 0.875rem;
  transition: all 0.2s;
}

.sort-toggle:hover {
  border-color: var(--accent);
  color: var(--text-primary);
}

.sort-toggle:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.task-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.task-item {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1rem;
  box-shadow: 0 1px 3px var(--shadow);
  transition: box-shadow 0.2s;
}

.task-item:hover {
  box-shadow: 0 2px 6px var(--shadow);
}

.task-header {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}

.task-title {
  font-size: 1.125rem;
  font-weight: 500;
  word-break: break-word;
  flex: 1;
  cursor: pointer;
  color: var(--text-primary);
  text-decoration: none;
}

.task-title:hover {
  color: var(--accent);
}

.task-title:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 0.25rem;
}

.task-time {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 0.75rem;
}

.task-time.never {
  color: var(--text-secondary);
  font-style: italic;
}

.task-time.recent {
  color: var(--success);
  font-weight: 500;
}

.task-actions {
  display: flex;
  gap: 0.5rem;
}

.btn {
  padding: 0.625rem 1.25rem;
  border: none;
  border-radius: 0.375rem;
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
  display: inline-block;
  text-align: center;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.btn:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.btn-primary {
  background: var(--accent);
  color: white;
  flex: 1;
}

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

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  background: var(--border);
}

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

.btn-danger:hover {
  background: var(--danger-hover);
}

.btn-small {
  padding: 0.375rem 0.75rem;
  font-size: 0.875rem;
  min-height: 36px;
}

.fab {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  border: none;
  font-size: 2rem;
  cursor: pointer;
  box-shadow: 0 4px 12px var(--shadow);
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 5;
}

.fab:hover {
  background: var(--accent-hover);
  transform: scale(1.05);
}

.fab:focus {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

.empty-state {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-secondary);
}

.empty-state svg {
  margin-bottom: 1rem;
  opacity: 0.5;
}

/* Form Screens */
.form-container {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 1.5rem;
  box-shadow: 0 1px 3px var(--shadow);
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
}

.form-group input[type="text"],
.form-group input[type="datetime-local"] {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 0.375rem;
  background: var(--bg-primary);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: inherit;
  transition: border-color 0.2s;
}

.form-group input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.form-actions .btn {
  flex: 1;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  text-decoration: none;
  margin-bottom: 1rem;
  padding: 0.5rem 0;
  font-weight: 500;
}

.back-link:hover {
  text-decoration: underline;
}

.back-link:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 0.25rem;
}

/* Edit Screen */
.completion-list {
  margin-top: 2rem;
}

.completion-list h3 {
  font-size: 1rem;
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.completion-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem;
  background: var(--bg-secondary);
  border-radius: 0.375rem;
  margin-bottom: 0.5rem;
}

.completion-time {
  color: var(--text-primary);
  font-size: 0.9375rem;
}

.delete-section {
  margin-top: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.error-message {
  background: rgba(220, 38, 38, 0.1);
  color: var(--danger);
  padding: 0.75rem;
  border-radius: 0.375rem;
  margin-bottom: 1rem;
  border: 1px solid var(--danger);
}

@media (min-width: 768px) {
  header h1 {
    font-size: 1.5rem;
  }

  main {
    padding: 2rem 1rem;
  }

  .task-item {
    padding: 1.25rem;
  }
}