:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --text: #16181d;
  --muted: #5d6470;
  --border: #e3e6eb;
  --green: #16a34a;
  --yellow: #eab308;
  --red: #dc2626;
  --off: #d9dde3;
  --accent: #2563eb;
  --zone: var(--off);
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --card: #181b21;
    --text: #eceef2;
    --muted: #9aa1ad;
    --border: #2a2f38;
    --off: #2d323b;
    --accent: #60a5fa;
  }
}

body[data-zone="green"] { --zone: var(--green); }
body[data-zone="yellow"] { --zone: var(--yellow); }
body[data-zone="red"] { --zone: var(--red); }

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  transition: background-color 0.4s;
}

body.alerting {
  background: color-mix(in srgb, var(--red) 14%, var(--bg));
}

.page {
  max-width: 640px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.top h1 { margin: 0; font-size: 1.6rem; letter-spacing: -0.02em; }
.tagline { margin: 4px 0 20px; color: var(--muted); }

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

.main-card { text-align: center; }

.lights {
  display: inline-flex;
  flex-direction: column;
  gap: 10px;
  padding: 12px;
  border-radius: 40px;
  background: color-mix(in srgb, var(--text) 6%, transparent);
}

.light {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--off);
  transition: background-color 0.2s, box-shadow 0.2s;
}

body[data-zone="red"] .light.red,
body[data-zone="yellow"] .light.yellow,
body[data-zone="green"] .light.green {
  background: var(--zone);
  box-shadow: 0 0 24px color-mix(in srgb, var(--zone) 60%, transparent);
}

.message h2 { margin: 16px 0 4px; font-size: 1.5rem; }
.message p { margin: 0; color: var(--muted); min-height: 1.5em; }

.meter { margin: 20px 0 8px; }
.meter-track {
  position: relative;
  height: 14px;
  border-radius: 7px;
  background: var(--off);
}
.meter-fill {
  height: 100%;
  width: 0;
  border-radius: 7px;
  background: var(--zone);
  transition: width 0.05s linear;
}
.mark {
  position: absolute;
  top: -4px;
  width: 3px;
  height: 22px;
  border-radius: 2px;
  transform: translateX(-1px);
}
.mark.floor { background: var(--muted); }
.mark.yellow { background: var(--yellow); }
.mark.red { background: var(--red); }
.meter-legend {
  display: flex;
  justify-content: space-between;
  margin-top: 6px;
  font-size: 0.8rem;
  color: var(--muted);
}

.calibration {
  margin: 16px 0;
  padding: 14px;
  border-radius: 12px;
  background: color-mix(in srgb, var(--accent) 10%, transparent);
}
.calibration p { margin: 4px 0 10px; }
.progress { height: 6px; border-radius: 3px; background: var(--off); overflow: hidden; }
.progress div { height: 100%; width: 0; background: var(--accent); transition: width 0.05s linear; }

.actions { display: flex; gap: 10px; justify-content: center; margin-top: 16px; flex-wrap: wrap; }

button {
  font: inherit;
  font-weight: 600;
  border-radius: 10px;
  padding: 10px 18px;
  cursor: pointer;
  border: 1px solid var(--border);
}
button:disabled { opacity: 0.5; cursor: default; }
button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
button.secondary { background: transparent; color: var(--text); }
body.running #start { display: none; }
.only-running { display: none !important; }
body.running .only-running { display: inline-flex !important; }
body.running .field-row.only-running { display: flex !important; }

.status { margin: 12px 0 0; font-size: 0.9rem; color: var(--muted); }
.status[data-kind="error"] { color: var(--red); }

h3 { margin: 0 0 12px; font-size: 1.05rem; }

.field { display: block; margin-bottom: 16px; }
.field > span { display: block; font-weight: 600; margin-bottom: 6px; }
.field small { display: block; color: var(--muted); margin-top: 4px; }
.field output { font-weight: 400; color: var(--muted); }
.field-row { gap: 10px; flex-wrap: wrap; margin-bottom: 16px; }

select, input[type="range"] { width: 100%; }
select {
  font: inherit;
  padding: 8px 10px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
}
input[type="range"] { accent-color: var(--accent); }

.check { display: flex; gap: 10px; align-items: flex-start; }
.check input { margin-top: 5px; }

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 12px;
}
.stats span { display: block; font-size: 0.8rem; color: var(--muted); }
.stats strong { font-size: 1.15rem; font-variant-numeric: tabular-nums; }

.foot { font-size: 0.85rem; color: var(--muted); }
.foot p { margin: 0 0 8px; }