:root {
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.5;
  font-weight: 400;

  color-scheme: light dark;
  color: #1a1a1a;
  background:  blue;

  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 20px;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

#app {
  width: 100%;
  max-width: 600px;
  margin: 0 auto;
}

.todo-container {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-radius: 20px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  padding: 40px 30px;
  min-height: 500px;
}

.todo-header {
  text-align: center;
  margin-bottom: 30px;
}

.todo-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin: 0;
  background: linear-gradient(rgb(31, 219, 21));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  color: #666;
  font-size: 1.1rem;
  margin: 10px 0 0 0;
  font-weight: 400;
}

.todo-input-section {
  margin-bottom: 30px;
}

.todo-form {
  display: flex;
  gap: 12px;
  align-items: center;
}

.todo-input {
  flex: 1;
  padding: 16px 20px;
  border: 2px solid #e1e5e9;
  border-radius: 12px;
  font-size: 1rem;
  font-family: inherit;
  transition: all 0.3s ease;
  background: white;
}

.todo-input:focus {
  outline: none;
  border-color: #667eea;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.add-btn {
  padding: 16px 24px;
  background: silver;
  color: white;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  gap: 8px;
  white-space: nowrap;
}

.add-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

.add-btn:active {
  transform: translateY(0);
}

.add-icon {
  font-size: 1.2rem;
  font-weight: 300;
}

.todo-controls {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 15px;
}

.filter-buttons {
  display: flex;
  gap: 8px;
  background: #f8f9fa;
  padding: 4px;
  border-radius: 10px;
}

.filter-btn {
  padding: 8px 16px;
  border: none;
  background: transparent;
  color: #666;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-size: 0.9rem;
  font-weight: 500;
}

.filter-btn.active {
  background: white;
  color: #667eea;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.filter-btn:hover:not(.active) {
  background: rgba(102, 126, 234, 0.1);
  color: #667eea;
}

.clear-btn {
  padding: 8px 16px;
  background: #ef4444;
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.3s ease;
}

.clear-btn:hover {
  background: #dc2626;
  transform: translateY(-1px);
}

.todo-list-container {
  min-height: 200px;
  margin-bottom: 20px;
}

.todo-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.todo-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  border-bottom: 1px solid #f0f0f0;
  transition: all 0.3s ease;
  animation: slideIn 0.3s ease;
}

.todo-item:last-child {
  border-bottom: none;
}

.todo-item.completed {
  opacity: 0.6;
}

.todo-item.completed .todo-text {
  text-decoration: line-through;
  color: #888;
}

.todo-item.todo-added {
  animation: slideIn 0.3s ease;
}

.todo-item.todo-removing {
  animation: slideOut 0.3s ease;
  opacity: 0;
  transform: translateX(-100%);
}

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

@keyframes slideOut {
  to {
    opacity: 0;
    transform: translateX(-100%);
  }
}

.todo-content {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
}

.todo-checkbox-label {
  display: flex;
  align-items: center;
  cursor: pointer;
  position: relative;
}

.todo-checkbox {
  opacity: 0;
  width: 0;
  height: 0;
}

.checkmark {
  width: 20px;
  height: 20px;
  border: 2px solid #ddd;
  border-radius: 6px;
  position: relative;
  transition: all 0.3s ease;
}

.checkmark::after {
  content: '';
  position: absolute;
  left: 6px;
  top: 2px;
  width: 6px;
  height: 10px;
  border: solid white;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.todo-checkbox:checked ~ .checkmark {
  background: #667eea;
  border-color: #667eea;
}

.todo-checkbox:checked ~ .checkmark::after {
  opacity: 1;
}

.todo-text {
  flex: 1;
  font-size: 1rem;
  line-height: 1.4;
  cursor: pointer;
  padding: 4px 0;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.todo-text:hover {
  background: rgba(102, 126, 234, 0.05);
  padding-left: 8px;
}

.todo-edit-input {
  flex: 1;
  padding: 8px 12px;
  border: 2px solid #667eea;
  border-radius: 6px;
  font-size: 1rem;
  font-family: inherit;
  background: white;
}

.todo-edit-input:focus {
  outline: none;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.delete-btn {
  padding: 8px;
  background: transparent;
  color: #ef4444;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.3s ease;
  opacity: 0.6;
}

.delete-btn:hover {
  opacity: 1;
  background: rgba(239, 68, 68, 0.1);
  transform: scale(1.1);
}

.delete-icon {
  font-size: 1.2rem;
  font-weight: 300;
}

.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: #888;
}

.empty-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.empty-state h3 {
  font-size: 1.5rem;
  margin: 0 0 8px 0;
  color: #666;
}

.empty-state p {
  margin: 0;
  font-size: 1rem;
}

.todo-stats {
  text-align: center;
  padding-top: 20px;
  border-top: 1px solid #f0f0f0;
}

.todo-count {
  color: #888;
  font-size: 0.9rem;
  font-weight: 500;
}

/* Responsive design */
@media (max-width: 768px) {
  body {
    padding: 10px;
  }
  
  .todo-container {
    padding: 30px 20px;
  }
  
  .todo-header h1 {
    font-size: 2rem;
  }
  
  .todo-form {
    flex-direction: column;
  }
  
  .todo-input {
    width: 100%;
  }
  
  .add-btn {
    width: 100%;
    justify-content: center;
  }
  
  .todo-controls {
    flex-direction: column;
    align-items: stretch;
  }
  
  .filter-buttons {
    justify-content: center;
  }
  
  .todo-item {
    padding: 12px 0;
  }
  
  .todo-text {
    font-size: 0.9rem;
  }
}

@media (max-width: 480px) {
  .todo-header h1 {
    font-size: 1.8rem;
  }
  
  .subtitle {
    font-size: 1rem;
  }
  
  .todo-input,
  .add-btn {
    padding: 14px 16px;
  }
  
  .filter-btn {
    padding: 6px 12px;
    font-size: 0.85rem;
  }
  
  .clear-btn {
    padding: 6px 12px;
    font-size: 0.85rem;
  }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
  :root {
    color: #e1e1e1;
    background: linear-gradient(135deg, #2d3748 0%, #4a5568 100%);
  }
  
  .todo-container {
    background: rgba(26, 32, 44, 0.95);
    color: #e1e1e1;
  }
  
  .todo-input {
    background: #2d3748;
    border-color: #4a5568;
    color: #e1e1e1;
  }
  
  .todo-input:focus {
    border-color: #667eea;
  }
  
  .filter-buttons {
    background: #2d3748;
  }
  
  .filter-btn.active {
    background: #4a5568;
  }
  
  .todo-item {
    border-color: #4a5568;
  }
  
  .checkmark {
    border-color: #4a5568;
  }
  
  .todo-text:hover {
    background: rgba(102, 126, 234, 0.1);
  }
  
  .todo-edit-input {
    background: #2d3748;
    color: #e1e1e1;
  }
  
  .todo-stats {
    border-color: #4a5568;
  }
  
  .empty-state {
    color: #a0aec0;
  }
  
  .empty-state h3 {
    color: #cbd5e0;
  }
}