:root {
  --primary: #4f46e5;
  --accent: #10b981;
  --danger: #ef4444;
  --bg: #f9fafb;
  --text: #1f2937;
  --card: #ffffff;
}

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

body {
  font-family: 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  padding: 20px;
}

.app {
  max-width: 600px;
  margin: auto;
  background: var(--card);
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.05);
}

header {
  text-align: center;
  margin-bottom: 20px;
}

header h1 {
  font-size: 2rem;
  color: var(--primary);
}

header p {
  font-size: 0.9rem;
  color: #6b7280;
}

.controls {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}

.controls input {
  flex: 1;
  padding: 12px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  font-size: 1rem;
}

.controls button {
  background: var(--primary);
  color: white;
  border: none;
  padding: 12px 20px;
  border-radius: 8px;
  cursor: pointer;
  font-weight: bold;
  transition: background 0.3s ease;
}

.controls button:hover {
  background: #4338ca;
}

.filters {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 20px;
}

.filters button {
  background: #e5e7eb;
  border: none;
  padding: 8px 16px;
  border-radius: 20px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.3s ease;
}

.filters button:hover {
  background: #d1d5db;
}

ul {
  list-style: none;
}

li {
  background: #f3f4f6;
  padding: 14px;
  margin-bottom: 10px;
  border-radius: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: transform 0.2s ease;
}

li:hover {
  transform: scale(1.01);
}

.completed {
  text-decoration: line-through;
  color: #9ca3af;
}

.actions i {
  margin-left: 15px;
  cursor: pointer;
  font-size: 1.1rem;
}

.actions .fa-check {
  color: var(--accent);
}

.actions .fa-trash {
  color: var(--danger);
}

footer {
  text-align: center;
  margin-top: 30px;
  font-size: 0.8rem;
  color: #6b7280;
}