/* One number matters here, so it gets the middle of the screen and the largest
   type. Everything else waits underneath. */

:root {
  --bg: #07080b;
  --panel: #0e1014;
  --line: #1b1e25;
  --text: #eef2f6;
  --dim: #8891a0;
  --faint: #59616f;
  --accent: #5eead4;
  --accent-dim: #0f3d3a;
  --mono: ui-monospace, SFMono-Regular, 'SF Mono', Menlo, Consolas, monospace;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  background: var(--bg);
}

body {
  min-height: 100vh;
  background:
    radial-gradient(60% 40% at 50% 0%, rgba(94, 234, 212, 0.09), transparent 70%),
    var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, Roboto, Arial, sans-serif;
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  font-variant-numeric: tabular-nums;
}

main {
  width: min(760px, 100%);
  margin: 0 auto;
  padding: clamp(20px, 4vw, 40px) clamp(16px, 4vw, 28px) 40px;
}

.label {
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--faint);
}

.dim {
  font-size: 13px;
  color: var(--faint);
}

/* ── top ────────────────────────────────────────────────────────────── */

.top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.address {
  margin-top: 4px;
  font-family: var(--mono);
  font-size: 18px;
}

.where {
  text-align: right;
  font-size: 13px;
  color: var(--dim);
  max-width: 60%;
}

/* ── gauge ──────────────────────────────────────────────────────────── */

.gauge-wrap {
  padding: clamp(20px, 5vw, 40px) 0 8px;
  text-align: center;
}

.gauge {
  display: block;
  width: min(360px, 78%);
  margin: 0 auto;
}

.arc-bg {
  fill: none;
  stroke: var(--line);
  stroke-width: 6;
  stroke-linecap: round;
}

.arc {
  fill: none;
  stroke: var(--accent);
  stroke-width: 6;
  stroke-linecap: round;
  opacity: 0.18;
}

.needle line {
  stroke: var(--accent);
  stroke-width: 3;
  stroke-linecap: round;
}

.needle {
  transform-origin: 100px 100px;
  transform: rotate(-90deg);
  transition: transform 0.25s cubic-bezier(0.2, 0.8, 0.3, 1);
}

.hub {
  fill: var(--accent);
}

.reading {
  margin-top: -14px;
  font-family: var(--mono);
  font-size: clamp(46px, 12vw, 84px);
  font-weight: 500;
  letter-spacing: -0.03em;
  line-height: 1;
}

.reading .unit {
  margin-left: 8px;
  font-family: inherit;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--dim);
}

.phase {
  margin-top: 8px;
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--faint);
}

.chart {
  display: block;
  width: 100%;
  height: 90px;
  margin: 14px 0 6px;
}

.chart .line {
  fill: none;
  stroke: var(--accent);
  stroke-width: 1.6;
  stroke-linejoin: round;
}

.chart .area {
  fill: var(--accent);
  opacity: 0.08;
  stroke: none;
}

.start {
  margin-top: 10px;
  padding: 13px 34px;
  border: 1px solid var(--accent);
  border-radius: 999px;
  background: transparent;
  color: var(--accent);
  font: inherit;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease;
}

.start:hover:not(:disabled) {
  background: var(--accent);
  color: #04211f;
}

.start:disabled {
  border-color: var(--line);
  color: var(--faint);
  cursor: default;
}

/* ── cards ──────────────────────────────────────────────────────────── */

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 10px;
  margin-top: 26px;
}

.card {
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--panel);
  transition: border-color 0.25s ease, background-color 0.25s ease;
}

.card.active {
  border-color: var(--accent-dim);
  background: linear-gradient(180deg, rgba(94, 234, 212, 0.06), var(--panel));
}

.card-label {
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--faint);
}

.card-value {
  margin: 4px 0 2px;
  font-family: var(--mono);
  font-size: 26px;
  letter-spacing: -0.02em;
}

.card-value .unit {
  margin-left: 6px;
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--dim);
}

/* ── footer ─────────────────────────────────────────────────────────── */

.foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 32px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  color: var(--faint);
}

.foot-links {
  display: inline-flex;
  gap: 16px;
}

.foot a {
  color: var(--dim);
  text-decoration: none;
}

.foot a:hover {
  color: var(--text);
}

@media (prefers-reduced-motion: reduce) {
  .needle {
    transition: none;
  }
}