:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --border: #e3e5e9;
  --text: #1b1d21;
  --muted: #6b7280;
  --accent: #2563eb;
  --accent-soft: #eaf0ff;
  --shadow: 0 1px 2px rgba(16, 18, 23, 0.05), 0 6px 16px rgba(16, 18, 23, 0.05);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #15171c;
    --card: #1d2026;
    --border: #2c3038;
    --text: #e9eaee;
    --muted: #9099a8;
    --accent: #6a9bff;
    --accent-soft: #232a3a;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 6px 16px rgba(0, 0, 0, 0.25);
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.page {
  max-width: 760px;
  margin: 0 auto;
  padding: 40px 20px 72px;
}

.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 28px;
}

h1 {
  margin: 0;
  font-size: 28px;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
  font-variant-numeric: tabular-nums;
}

.clear-button {
  flex: none;
  padding: 9px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  font: inherit;
  font-size: 14px;
  font-weight: 550;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: border-color 0.15s, color 0.15s;
}

.clear-button:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.clear-button:active { transform: translateY(1px); }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 18px 20px 8px;
  margin-bottom: 16px;
}

.card-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

h2 {
  margin: 0;
  font-size: 17px;
  font-weight: 650;
  letter-spacing: -0.01em;
}

.count {
  flex: none;
  color: var(--muted);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}

.items {
  list-style: none;
  margin: 0;
  padding: 6px 0 10px;
}

.item {
  display: flex;
  align-items: flex-start;
  gap: 11px;
  padding: 8px 6px;
  margin: 0 -6px;
  border-radius: 7px;
  cursor: pointer;
  user-select: none;
}

.item:hover { background: var(--accent-soft); }

.item input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.box {
  flex: none;
  width: 19px;
  height: 19px;
  margin-top: 2px;
  border: 1.5px solid var(--border);
  border-radius: 5px;
  background: transparent;
  transition: background 0.12s, border-color 0.12s;
}

.item input:focus-visible + .box {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.item input:checked + .box {
  background: var(--accent) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none' stroke='white' stroke-width='2.4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M3.5 8.5l3 3 6-6'/%3E%3C/svg%3E") center/13px no-repeat;
  border-color: var(--accent);
}

.text { transition: color 0.12s; }

/* Ticked options stay exactly where they are — just struck through. */
.item input:checked ~ .text {
  text-decoration: line-through;
  text-decoration-thickness: 1.5px;
  color: var(--muted);
}

.empty {
  color: var(--muted);
  font-size: 14px;
  padding: 10px 0 14px;
  margin: 0;
}