:root {
  color-scheme: light;
  --page: #f4f3f0;
  --surface: #fcfcfb;
  --border: #e2e0da;
  --text-primary: #0b0b0b;
  --text-secondary: #52514e;
  --text-muted: #7a7974;
  --grid: #ebe9e4;
  --temp: #eb6834;
  --hum: #2a78d6;
  --accent: #2a78d6;
  --accent-text: #ffffff;
  --ok: #008300;
  --bad: #e34948;
  --bad-bg: #fcebeb;
  --badge-admin-bg: #ecebfb;
  --badge-admin-text: #3c3489;
  --badge-viewer-bg: #ebf2fb;
  --badge-viewer-text: #0c447c;
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --page: #121211;
    --surface: #1a1a19;
    --border: #2e2e2c;
    --text-primary: #f0efec;
    --text-secondary: #c3c2b7;
    --text-muted: #8f8e86;
    --grid: #2a2a28;
    --temp: #d95926;
    --hum: #3987e5;
    --accent: #3987e5;
    --ok: #3fae3f;
    --bad: #e66767;
    --bad-bg: #3a1c1c;
    --badge-admin-bg: #2c2860;
    --badge-admin-text: #cecbf6;
    --badge-viewer-bg: #0c2c4d;
    --badge-viewer-text: #b5d4f4;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; padding: 0 16px 48px;
  background: var(--page); color: var(--text-primary);
  font: 15px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
}
main { max-width: 1100px; margin: 0 auto; }
a { color: var(--accent); }

/* top bar */
.topbar { max-width: 1100px; margin: 0 auto; padding: 16px 0 20px; display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
.brand { font-size: 18px; font-weight: 600; margin-right: 8px; }
.nav { display: flex; gap: 4px; flex: 1; }
.nav a { color: var(--text-secondary); text-decoration: none; padding: 6px 10px; border-radius: 8px; font-size: 14px; }
.nav a.active, .nav a:hover { background: var(--surface); color: var(--text-primary); }
.who { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--text-secondary); }
.who form { margin: 0; }

/* shared pieces */
h1 { font-size: 22px; font-weight: 600; margin: 0 0 16px; }
h2 { font-size: 16px; font-weight: 600; margin: 0 0 12px; }
h3 { font-size: 13px; font-weight: 500; color: var(--text-secondary); margin: 0 0 4px; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 16px 18px; }
.badge { display: inline-block; font-size: 12px; padding: 1px 8px; border-radius: 999px; }
.badge.admin { background: var(--badge-admin-bg); color: var(--badge-admin-text); }
.badge.viewer { background: var(--badge-viewer-bg); color: var(--badge-viewer-text); }
.btn { font: inherit; font-size: 14px; padding: 7px 14px; border-radius: 8px; border: 1px solid var(--border);
       background: var(--surface); color: var(--text-primary); cursor: pointer; }
.btn:hover { border-color: var(--text-muted); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-text); }
.btn.danger { color: var(--bad); }
.btn.small { font-size: 13px; padding: 4px 10px; }
.btn:disabled { opacity: .5; cursor: default; }
input, select { font: inherit; font-size: 14px; padding: 7px 10px; border-radius: 8px;
                border: 1px solid var(--border); background: var(--page); color: var(--text-primary); }
.error { color: var(--bad); background: var(--bad-bg); border-radius: 8px; padding: 8px 12px; font-size: 14px; }
.muted { color: var(--text-muted); font-size: 13px; }

/* dashboard */
.status-row { display: flex; justify-content: flex-end; margin: -8px 0 12px; }
.status { font-size: 13px; color: var(--text-secondary); display: flex; align-items: center; gap: 6px; }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--text-muted); }
.dot.ok { background: var(--ok); }
.dot.bad { background: var(--bad); }
.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-bottom: 16px; }
.tile-label { font-size: 13px; color: var(--text-secondary); display: flex; align-items: center; gap: 8px; }
.swatch { width: 10px; height: 10px; border-radius: 3px; }
.tile-value { font-size: 44px; font-weight: 600; line-height: 1.1; margin-top: 6px; font-variant-numeric: tabular-nums; }
.tile-value small { font-size: 20px; font-weight: 400; color: var(--text-secondary); margin-left: 4px; }
.tile-sub { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.window { margin-bottom: 16px; }
.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 700px) { .pair { grid-template-columns: 1fr; } }
.chart-box { position: relative; height: 180px; }

/* login + message pages */
.center { min-height: 70vh; display: flex; align-items: center; justify-content: center; }
.narrow { max-width: 400px; width: 100%; text-align: center; padding: 32px 28px; }
.narrow p { color: var(--text-secondary); }
.google-btn { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; margin-top: 8px; }

/* privacy policy / terms */
.legal { max-width: 760px; margin: 24px auto; padding: 24px 28px; }
.legal h2 { margin-top: 20px; }
.legal li { margin-bottom: 6px; }
.legal hr { border: none; border-top: 1px solid var(--border); margin: 20px 0; }

/* user management */
.add-form { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.add-form input[type=email] { flex: 1; min-width: 220px; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th { text-align: left; font-weight: 500; color: var(--text-secondary); font-size: 13px; padding: 8px 8px; border-bottom: 1px solid var(--border); }
td { padding: 10px 8px; border-bottom: 1px solid var(--border); vertical-align: middle; }
tr:last-child td { border-bottom: none; }
.table-wrap { overflow-x: auto; }
@media (max-width: 700px) { .hide-mobile { display: none; } }