:root {
  --bg: #0f172a;
  --panel: #1e293b;
  --fg: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --error: #f87171;
  --ok: #34d399;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, sans-serif;
  background: var(--bg);
  color: var(--fg);
  padding: 0 16px env(safe-area-inset-bottom);
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
}

h1 { font-size: 1.2rem; margin: 0; }

.badge {
  font-size: 0.8rem;
  padding: 2px 10px;
  border-radius: 999px;
  background: var(--ok);
  color: #062;
}
.badge.off { background: var(--muted); color: #111; }

main { max-width: 640px; margin: 0 auto; }

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-bottom: 16px;
}

button {
  background: var(--accent);
  color: #002;
  border: 0;
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 1rem;
  cursor: pointer;
}
button:disabled { opacity: 0.4; cursor: not-allowed; }

input {
  background: var(--panel);
  color: var(--fg);
  border: 1px solid #334155;
  border-radius: 8px;
  padding: 8px 10px;
  font-size: 1rem;
}

.stride { display: flex; flex-direction: column; font-size: 0.8rem; color: var(--muted); }
.stride input { width: 80px; }

.live {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
}

.metric {
  background: var(--panel);
  border-radius: 12px;
  padding: 14px;
  display: flex;
  flex-direction: column;
}
.metric .label { font-size: 0.75rem; color: var(--muted); }
.metric span:nth-child(2) { font-size: 1.8rem; font-weight: 700; }
.metric .unit { font-size: 0.75rem; color: var(--muted); }

.hint { font-size: 0.75rem; color: var(--muted); }
.error { color: var(--error); }

button.secondary { background: var(--panel); color: var(--fg); border: 1px solid #334155; }

#calibration { margin: 12px 0; background: var(--panel); border-radius: 12px; padding: 12px 14px; }
#calibration summary { cursor: pointer; font-weight: 600; }
.cal-fields { display: flex; flex-wrap: wrap; gap: 8px; align-items: flex-end; margin-top: 8px; }
.cal-fields label { display: flex; flex-direction: column; font-size: 0.8rem; color: var(--muted); }
.cal-fields input { width: 140px; }

table { width: 100%; border-collapse: collapse; margin-top: 8px; }
th, td { text-align: left; padding: 8px; border-bottom: 1px solid #334155; font-size: 0.9rem; }
th { color: var(--muted); font-weight: 600; }

/* cards + charts */
.card { background: var(--panel); border-radius: 12px; padding: 14px; margin: 12px 0; }
.card-title { font-size: 0.75rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: 8px; }
.chart { width: 100%; height: 80px; display: block; }
.chart.tall { height: 120px; }

/* belt control */
.belt-main { display: flex; }
.big { width: 100%; padding: 18px; font-size: 1.3rem; font-weight: 700; }
.big-start { background: var(--ok); }
.big-stop { background: var(--error); color: #300; }
.belt-speed { display: flex; align-items: center; justify-content: center; gap: 16px; margin: 14px 0; }
.round { width: 52px; height: 52px; border-radius: 50%; font-size: 1.6rem; line-height: 1; padding: 0; }
.target { text-align: center; min-width: 90px; }
.target span:first-child { font-size: 2rem; font-weight: 700; display: block; }
.target .unit { font-size: 0.7rem; color: var(--muted); }
.presets { display: flex; gap: 8px; }
.preset { flex: 1; display: flex; flex-direction: column; align-items: center; gap: 2px; }
.preset small { color: var(--muted); font-size: 0.65rem; }

/* dashboard */
.dash { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 12px; }
.stats .big-num { font-size: 1.8rem; font-weight: 700; }
.stats .sub { font-size: 0.75rem; color: var(--muted); margin-top: 4px; }
.dots { display: flex; gap: 6px; margin: 8px 0; }
.dot { width: 16px; height: 16px; border-radius: 50%; background: #475569; }
.dot.on { background: var(--ok); }
.goal-row { display: flex; gap: 8px; align-items: flex-end; margin-top: 10px; }
.goal { display: flex; flex-direction: column; font-size: 0.8rem; color: var(--muted); }
.goal input { width: 90px; }