:root {
  color-scheme: dark;
  --ink: #f4f7f5;
  --muted: #98aaa7;
  --panel: rgba(15, 29, 31, 0.86);
  --line: rgba(202, 230, 225, 0.14);
  --water: #071b21;
  --true: #8fddff;
  --induced: #c3a6ff;
  --apparent: #f7c76a;
  --sail: #ef7f75;
  --keel: #a8df78;
  --rudder: #63b3ff;
  --hull: #b9c4c7;
  --total: #f7f4e7;
  --accent: #69d6bd;
  --danger: #ff5f68;
}

* {
  box-sizing: border-box;
}
body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 70% 15%, rgba(45, 119, 123, 0.2), transparent 33rem), var(--water);
  color: var(--ink);
  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    sans-serif;
}

button,
input {
  font: inherit;
}
.app {
  max-width: 1440px;
  margin: 0 auto;
  padding: 24px;
}
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}
.brand {
  color: var(--ink);
  text-decoration: none;
  font-weight: 650;
  letter-spacing: -0.02em;
}
.topnav {
  display: flex;
  align-items: center;
  gap: 6px;
}
.topnav a {
  padding: 8px 12px;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.82rem;
}
.topnav a:hover {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.06);
}
.topnav a[aria-current='page'] {
  color: var(--ink);
  background: rgba(105, 214, 189, 0.13);
}
header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 20px;
}
h1 {
  margin: 0;
  font-size: clamp(1.45rem, 3vw, 2.35rem);
  letter-spacing: -0.04em;
  font-weight: 650;
}
.eyebrow {
  margin: 0 0 7px;
  color: var(--accent);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.layout {
  display: grid;
  grid-template-columns: minmax(390px, 430px) minmax(0, 1fr);
  gap: 18px;
}
.panel {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--panel);
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.24);
  backdrop-filter: blur(18px);
}
.controls {
  padding: 20px;
}
.auto-toggle {
  display: flex;
  align-items: center;
  gap: 7px;
  color: var(--muted);
  font-size: 0.76rem;
  cursor: pointer;
}
.auto-toggle input {
  accent-color: var(--accent);
}
.pill-button {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 7px 12px;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
}
.pill-button:hover {
  background: rgba(255, 255, 255, 0.06);
}
.boat-config {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}
.boat-config summary {
  color: var(--muted);
  cursor: pointer;
  font-size: 0.78rem;
}
.parameter-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 14px;
}
.parameter {
  display: grid;
  gap: 6px;
}
.parameter label {
  color: var(--muted);
  font-size: 0.72rem;
}
.parameter span {
  font-size: 0.84rem;
  font-variant-numeric: tabular-nums;
}
.parameter input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px 9px;
  color: var(--ink);
  background: rgba(5, 16, 18, 0.42);
}
.direction-controls {
  display: grid;
  grid-template-columns: 1fr;
  justify-items: center;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--line);
}
.direction-controls .angle-dial {
  width: 142px;
}
.speed-controls {
  display: grid;
  grid-template-columns: 1fr;
  padding-top: 20px;
}
.computed-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-top: 18px;
}
.computed {
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(5, 16, 18, 0.3);
}
.computed span {
  display: block;
  color: var(--muted);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
}
.computed strong {
  display: block;
  margin-top: 3px;
  font-size: 0.9rem;
  font-weight: 550;
  font-variant-numeric: tabular-nums;
}
.dial-control {
  min-width: 0;
}
.dial-control.auto-controlled {
  opacity: 0.72;
}
.dial-control .control-head {
  display: grid;
  justify-items: center;
  gap: 3px;
  margin-bottom: 10px;
  text-align: center;
}
.control-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}
.control label {
  font-size: 0.86rem;
  color: var(--muted);
}
output {
  color: var(--ink);
  font-variant-numeric: tabular-nums;
  font-size: 0.88rem;
}
input[type='range'] {
  width: 100%;
  accent-color: var(--accent);
  cursor: pointer;
}
.dial-wrap {
  display: grid;
  justify-items: center;
  gap: 8px;
}
.dial-native {
  position: absolute;
  width: 1px !important;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}
.angle-dial {
  --no-go-start: -36.5deg;
  --no-go-span: 73deg;
  position: relative;
  width: 142px;
  max-width: 100%;
  aspect-ratio: 1;
  border: 1px solid var(--line);
  border-radius: 50%;
  background:
    radial-gradient(circle, rgba(105, 214, 189, 0.12) 0 5px, transparent 6px),
    conic-gradient(
      from var(--no-go-start),
      rgba(255, 95, 104, 0.3) 0deg var(--no-go-span),
      transparent var(--no-go-span) 360deg
    ),
    repeating-conic-gradient(
      from -1deg,
      rgba(244, 247, 245, 0.18) 0deg 1deg,
      transparent 1deg 15deg
    ),
    rgba(5, 16, 18, 0.42);
  cursor: crosshair;
  touch-action: none;
  user-select: none;
}
.dial-native:focus-visible + .angle-dial {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}
.dial-pointer {
  position: absolute;
  inset: 14px 50% 50%;
  width: 2px;
  background: var(--true);
  transform-origin: 50% 100%;
  transform: translateX(-50%) rotate(var(--angle));
}
.dial-pointer::before {
  content: '';
  position: absolute;
  top: -2px;
  left: 50%;
  width: 10px;
  height: 10px;
  border: 2px solid var(--true);
  border-radius: 50%;
  background: var(--water);
  transform: translate(-50%, -50%);
}
.dial-label {
  position: absolute;
  color: var(--muted);
  font-size: 0.62rem;
  pointer-events: none;
}
.dial-label.bow {
  top: 8px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--ink);
}
.dial-label.stbd {
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
}
.dial-label.aft {
  bottom: 7px;
  left: 50%;
  transform: translateX(-50%);
}
.dial-label.port {
  left: 8px;
  top: 50%;
  transform: translateY(-50%);
}
.sail-dial {
  background:
    radial-gradient(circle, rgba(239, 127, 117, 0.12) 0 5px, transparent 6px),
    repeating-conic-gradient(
      from -1deg,
      rgba(244, 247, 245, 0.18) 0deg 1deg,
      transparent 1deg 15deg
    ),
    rgba(5, 16, 18, 0.42);
}
.sail-dial .dial-pointer {
  background: var(--sail);
}
.sail-dial .dial-pointer::before {
  border-color: var(--sail);
}
.helm-dial {
  background:
    radial-gradient(circle, rgba(99, 179, 255, 0.12) 0 5px, transparent 6px),
    repeating-conic-gradient(
      from -1deg,
      rgba(244, 247, 245, 0.18) 0deg 1deg,
      transparent 1deg 15deg
    ),
    rgba(5, 16, 18, 0.42);
}
.helm-dial .dial-pointer {
  background: var(--rudder);
}
.helm-dial .dial-pointer::before {
  border-color: var(--rudder);
}
.dial-caption {
  color: var(--muted);
  font-size: 0.68rem;
  text-align: center;
  margin-top: 8px;
}
.hint {
  color: var(--muted);
  font-size: 0.72rem;
  margin-top: 7px;
  line-height: 1.35;
}
.visual-column {
  display: grid;
  gap: 18px;
  align-content: start;
}
.stage {
  min-height: 560px;
  position: relative;
  overflow: hidden;
}
#scene {
  width: 100%;
  height: 560px;
  display: block;
}
.force-card {
  position: relative;
  height: 340px;
  overflow: hidden;
}
#forceScene {
  width: 100%;
  height: 340px;
  display: block;
}
.force-head {
  position: absolute;
  z-index: 1;
  top: 15px;
  left: 18px;
  right: 18px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
  pointer-events: none;
}
.force-head strong {
  font-size: 0.82rem;
  font-weight: 550;
}
.force-head span {
  color: var(--muted);
  font-size: 0.72rem;
}
.debug-card {
  padding: 0;
}
.debug-summary {
  padding: 18px;
  cursor: pointer;
}
.debug-card[open] .debug-summary {
  border-bottom: 1px solid var(--line);
}
.debug-body {
  padding: 14px 18px 18px;
}
.debug-title {
  display: inline-grid;
  gap: 3px;
  margin-left: 7px;
  vertical-align: middle;
}
.debug-title strong {
  font-size: 0.82rem;
  font-weight: 550;
}
.debug-title span,
.copy-status {
  color: var(--muted);
  font-size: 0.72rem;
}
.debug-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  margin-bottom: 12px;
}
.debug-output {
  display: block;
  width: 100%;
  min-height: 290px;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px;
  color: var(--ink);
  background: rgba(5, 16, 18, 0.55);
  font:
    12px/1.48 ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  white-space: pre;
  tab-size: 2;
}
.legend {
  position: absolute;
  top: 17px;
  left: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  pointer-events: none;
}
.legend-item {
  display: flex;
  align-items: center;
  gap: 7px;
  color: var(--muted);
  font-size: 0.72rem;
}
.legend-item.secondary {
  opacity: 0.58;
}
.swatch {
  width: 20px;
  height: 3px;
  border-radius: 999px;
  background: var(--c);
}
.metrics {
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 12px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
  width: auto;
}
.metric {
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: rgba(5, 16, 18, 0.72);
}
.metric span {
  display: block;
  color: var(--muted);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.metric strong {
  display: block;
  margin-top: 3px;
  font-size: 0.9rem;
  font-weight: 550;
  font-variant-numeric: tabular-nums;
}

@media (max-width: 780px) {
  .app {
    padding: 15px;
  }
  header {
    align-items: start;
  }
  .layout {
    grid-template-columns: 1fr;
  }
  .stage {
    min-height: 520px;
  }
  #scene {
    height: 520px;
  }
}
@media (max-width: 480px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }
  .direction-controls,
  .speed-controls {
    grid-template-columns: 1fr;
  }
  .metrics {
    grid-template-columns: 1fr 1fr;
  }
  .metric:last-child {
    grid-column: 1 / -1;
  }
}