:root {
  --primary: #4f46e5;
  --bg: #f5f6fa;
  --card-bg: #ffffff;
  --text: #1f2430;
  --muted: #7a7f8a;
  --danger: #e5484d;
  --radius: 10px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  justify-content: center;
  padding: 40px 16px;
}

.app {
  width: 100%;
  max-width: 480px;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
  padding: 24px;
}

.app__header h1 {
  margin: 0 0 4px;
  font-size: 22px;
}

.app__subtitle {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 13px;
}

.task-form {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.task-form input {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid #dfe1e8;
  border-radius: var(--radius);
  font-size: 14px;
}

.task-form button {
  padding: 10px 16px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 14px;
}

.task-form button:hover {
  opacity: 0.9;
}

.stats {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 16px;
}

.task-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.task-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border: 1px solid #eceef3;
  border-radius: var(--radius);
}

.task-item.done .task-item__text {
  text-decoration: line-through;
  color: var(--muted);
}

.task-item__text {
  flex: 1;
  font-size: 14px;
}

.task-item__delete {
  background: none;
  border: none;
  color: var(--danger);
  cursor: pointer;
  font-size: 14px;
}

.app__footer {
  margin-top: 20px;
  text-align: right;
  font-size: 11px;
  color: var(--muted);
}