:root {
  --bg: #f4f5f7;
  --card: #ffffff;
  --text: #1c1e21;
  --muted: #6b7280;
  --accent: #3b82f6;
  --accent-text: #ffffff;
  --danger: #ef4444;
  --border: #e5e7eb;
  --done: #9ca3af;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --card: #1f2227;
    --text: #f3f4f6;
    --muted: #9ca3af;
    --accent: #60a5fa;
    --accent-text: #0b1220;
    --danger: #f87171;
    --border: #2c2f36;
    --done: #6b7280;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: var(--card);
}

header h1 { font-size: 1.1rem; margin: 0; }

nav { display: flex; gap: 0.5rem; }

nav button {
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 0.5rem 0.9rem;
  border-radius: 8px;
  font-size: 0.95rem;
  cursor: pointer;
}

nav button.active { background: var(--accent); color: var(--accent-text); }

main { max-width: 720px; margin: 0 auto; padding: 1.25rem; }

section { display: none; }
section.active { display: block; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem;
  margin-bottom: 1rem;
}

.card h2 { margin-top: 0; font-size: 1.05rem; }

.row { display: flex; align-items: center; gap: 0.6rem; margin-bottom: 0.4rem; }
.row.muted { color: var(--muted); font-size: 0.85rem; }

.item {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--border);
}
.item:last-child { border-bottom: none; }
.item.done .label { text-decoration: line-through; color: var(--done); }
.item .label { flex: 1; white-space: pre-line; }

.section-header { cursor: pointer; display: flex; align-items: center; justify-content: space-between; user-select: none; }
.section-header h2 { margin: 0; }
.section-header .chevron { transition: transform 0.15s; color: var(--muted); }
.collapsed .chevron { transform: rotate(-90deg); }
.collapsed .card-body { display: none; }
.card-body { margin-top: 0.75rem; }

.add-toggle { font-size: 1.3rem; line-height: 1; font-weight: 600; }
.add-form[hidden] { display: none; }
.add-form { margin-bottom: 0.75rem; }

.list-body.collapsed { display: none; }
.chevron.rotated { transform: rotate(-90deg); }

button.icon {
  border: none;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 1rem;
  padding: 0.2rem 0.4rem;
}
button.icon:hover { color: var(--danger); }

input[type="text"], input[type="datetime-local"], input[type="number"], textarea, select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.5rem 0.6rem;
  font-size: 0.95rem;
  width: 100%;
}

textarea { resize: vertical; min-height: 3rem; }

.btn {
  background: var(--accent);
  color: var(--accent-text);
  border: none;
  border-radius: 8px;
  padding: 0.5rem 0.9rem;
  font-size: 0.95rem;
  cursor: pointer;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.weekday-picker { display: flex; gap: 0.3rem; flex-wrap: wrap; }
.weekday-picker label {
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.3rem 0.5rem;
  font-size: 0.8rem;
  cursor: pointer;
  user-select: none;
}
.weekday-picker input { display: none; }
.weekday-picker input:checked + span { color: var(--accent-text); }
.weekday-picker label:has(input:checked) { background: var(--accent); border-color: var(--accent); }

.pin-badge {
  font-size: 0.7rem;
  background: var(--accent);
  color: var(--accent-text);
  border-radius: 999px;
  padding: 0.1rem 0.5rem;
}

.hint { color: var(--muted); font-size: 0.85rem; margin-top: 0.25rem; }

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  align-items: center;
  justify-content: center;
  z-index: 100;
}
.modal-box {
  background: var(--card);
  border-radius: 12px;
  padding: 1.25rem;
  width: 90%;
  max-width: 420px;
  max-height: 80vh;
  overflow-y: auto;
}