:root {
  color-scheme: light dark;
  --bg: #f5f6fa;
  --card: #ffffff;
  --text: #1c1c1e;
  --muted: #6b7280;
  --accent: #2563eb;
  --danger: #dc2626;
  --border: #e5e7eb;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  background: var(--bg);
  color: var(--text);
  padding-bottom: 40px;
}

header {
  padding: 20px 16px 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

header h1 {
  font-size: 20px;
  margin: 0;
}

header a.back {
  text-decoration: none;
  color: var(--accent);
  font-size: 16px;
}

main {
  padding: 0 16px;
  max-width: 480px;
  margin: 0 auto;
}

.card {
  background: var(--card);
  border-radius: 14px;
  padding: 16px;
  margin-bottom: 14px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.member-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.member-list li {
  margin-bottom: 10px;
}

.member-list a {
  display: block;
  background: var(--card);
  border-radius: 14px;
  padding: 16px;
  text-decoration: none;
  color: var(--text);
  font-size: 17px;
  font-weight: 600;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.member-list a:active { opacity: 0.7; }

form.inline {
  display: flex;
  gap: 8px;
}

input[type="text"], input[type="time"] {
  flex: 1;
  padding: 10px 12px;
  border-radius: 10px;
  border: 1px solid var(--border);
  font-size: 16px;
  background: var(--card);
  color: var(--text);
}

button {
  padding: 10px 16px;
  border-radius: 10px;
  border: none;
  background: var(--accent);
  color: white;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
}

button:active { opacity: 0.8; }

button.secondary {
  background: var(--border);
  color: var(--text);
}

button.danger {
  background: var(--danger);
}

.checklist {
  list-style: none;
  margin: 0 0 12px;
  padding: 0;
}

.checklist li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
  font-size: 16px;
}

.checklist li:last-child { border-bottom: none; }

.checklist button.danger {
  padding: 4px 10px;
  font-size: 13px;
}

.muted { color: var(--muted); font-size: 14px; }

.status-msg {
  margin-top: 10px;
  font-size: 14px;
}

.status-msg.ok { color: #059669; }
.status-msg.error { color: var(--danger); }

.section-title {
  font-size: 15px;
  font-weight: 700;
  margin: 0 0 10px;
}

.install-guide {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b0b0d;
    --card: #1c1c1e;
    --text: #f2f2f7;
    --muted: #9ca3af;
    --border: #33343a;
  }
}