:root {
  --accent: #2563eb;
  --accent-strong: #1d4ed8;
  --bg: #f1f5f9;
  --surface: #ffffff;
  --text: #0f172a;
  --text-soft: #64748b;
  --ring-track: #e2e8f0;
  --radius: 20px;
  --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background:
    radial-gradient(1200px 600px at 50% -200px, #dbeafe 0%, rgba(219, 234, 254, 0) 60%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

.topbar {
  padding: 18px 24px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.05rem;
}

.brand-icon {
  width: 30px;
  height: 30px;
  border-radius: 8px;
}

.container {
  flex: 1;
  width: 100%;
  max-width: 640px;
  margin: 0 auto;
  padding: 12px 20px 40px;
}

.hero { text-align: center; padding: 8px 0 24px; }

.gauge-wrap {
  position: relative;
  width: min(260px, 70vw);
  margin: 0 auto;
}

.gauge { display: block; width: 100%; height: auto; }

.gauge-bg { fill: none; stroke: var(--ring-track); stroke-width: 14; }

.gauge-ring {
  fill: none;
  stroke: var(--accent);
  stroke-width: 14;
  stroke-linecap: round;
  transform: rotate(-90deg);
  transform-origin: center;
  transition: stroke-dashoffset 0.25s ease;
}

.gauge-center {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
}

.gauge-value {
  font-size: clamp(3rem, 14vw, 4.5rem);
  font-weight: 800;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

.gauge-unit { color: var(--text-soft); font-weight: 600; margin-top: 4px; }

.status {
  color: var(--text-soft);
  margin-top: 18px;
  font-size: 0.95rem;
  min-height: 1.2em;
}

.status[data-tone="error"] { color: #dc2626; }

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin: 8px 0 24px;
}

.btn {
  appearance: none;
  border: 1px solid #cbd5e1;
  background: var(--surface);
  color: var(--text);
  padding: 12px 20px;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.08s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover { box-shadow: var(--shadow); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.5; cursor: default; }

.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-strong); }

.cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.card {
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px 20px;
}

.card-label {
  color: var(--text-soft);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.card .value {
  font-size: 1.6rem;
  font-weight: 800;
  margin-top: 6px;
  font-variant-numeric: tabular-nums;
}

.footer {
  text-align: center;
  color: var(--text-soft);
  font-size: 0.8rem;
  padding: 20px 24px;
}