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

body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: system-ui, -apple-system, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  padding: 1rem;
}

main {
  width: 100%;
  max-width: 420px;
  padding: 2rem;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 1rem;
  backdrop-filter: blur(10px);
}

h1 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  text-align: center;
}

#todo-form {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

#todo-input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: none;
  border-radius: 0.5rem;
  font-size: 1rem;
}

#todo-form button {
  padding: 0.75rem 1.25rem;
  border: none;
  border-radius: 0.5rem;
  background: #fff;
  color: #667eea;
  font-weight: 600;
  cursor: pointer;
}

#todo-list {
  list-style: none;
  margin-bottom: 1rem;
}

#todo-list li {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 0.5rem;
  margin-bottom: 0.5rem;
}

#todo-list li.done span {
  text-decoration: line-through;
  opacity: 0.6;
}

#todo-list input[type="checkbox"] {
  width: 1.1rem;
  height: 1.1rem;
  cursor: pointer;
}

#todo-list span {
  flex: 1;
}

.remove {
  background: none;
  border: none;
  color: #fff;
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0.7;
  line-height: 1;
}

.remove:hover {
  opacity: 1;
}

#todo-count {
  text-align: center;
  font-size: 0.9rem;
  opacity: 0.8;
}