:root {
  color-scheme: light dark;
  --bg: #f7f7f8;
  --card: #ffffff;
  --text: #1a1a1a;
  --muted: #666;
  --border: #e2e2e2;
  --accent: #2563eb;
  --good: #15803d;
  --bad: #b91c1c;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16171a;
    --card: #1f2023;
    --text: #eee;
    --muted: #999;
    --border: #333;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  padding-block: 24px;
  padding-inline: 16px;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.container { max-width: 900px; margin: 0 auto; }
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 20px;
}
h1 { font-size: 1.4rem; }
h2 { font-size: 1.1rem; margin-top: 0; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 8px;
}
table { width: 100%; border-collapse: collapse; }
th, td { padding: 8px; border-bottom: 1px solid var(--border); text-align: left; }
input[type=number], input[type=text], input[type=email], input[type=password], select {
  width: 90px;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
}
input[type=email], input[type=password], input[type=text] { width: 100%; max-width: 320px; }
button {
  background: var(--accent);
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.95rem;
}
button.secondary { background: #6b7280; }
button.danger { background: var(--bad); }
.stats { display: flex; gap: 16px; flex-wrap: wrap; }
.stat { flex: 1; min-width: 140px; }
.stat .value { font-size: 1.6rem; font-weight: 600; }
.stat .label { color: var(--muted); font-size: 0.85rem; }
.positive { color: var(--good); }
.negative { color: var(--bad); }
.weeknav { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.error { color: var(--bad); margin-bottom: 12px; }
.notice { background: #dbeafe; color: #1e3a8a; padding: 10px 14px; border-radius: 8px; margin-bottom: 16px; font-family: monospace; }
form.inline { display: inline; }
.muted { color: var(--muted); font-size: 0.85rem; }