:root {
  color-scheme: dark;
  --ink: #f4f7f5;
  --muted: #98aaa7;
  --panel: rgba(15, 29, 31, 0.86);
  --line: rgba(202, 230, 225, 0.14);
  --water: #071b21;
  --water-line: #69d6bd;
  --accent: #69d6bd;
  --chain: #f7c76a;
  --wind: #8fddff;
  --anchor-metal: #dce7e4;
  --sand: #625946;
  --hull: #e7efec;
  --hull-shadow: #547175;
  --keel-metal: #78989a;
  --sail-cloth: #d9e8e5;
}

* {
  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,
select {
  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 {
  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(300px, 360px) 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;
  display: grid;
  gap: 22px;
  align-content: start;
}
.control {
  display: grid;
  gap: 10px;
}
.control-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}
.control label {
  color: var(--muted);
  font-size: 0.86rem;
}
output {
  color: var(--ink);
  font-size: 0.88rem;
  font-variant-numeric: tabular-nums;
}
input[type='range'] {
  width: 100%;
  accent-color: var(--accent);
  cursor: pointer;
}
select {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 9px 10px;
  color: var(--ink);
  background: rgba(5, 16, 18, 0.55);
}
.summary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}
.stat {
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(5, 16, 18, 0.3);
}
.stat span {
  display: block;
  color: var(--muted);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
}
.stat strong {
  display: block;
  margin-top: 3px;
  font-size: 0.9rem;
  font-weight: 550;
  font-variant-numeric: tabular-nums;
}
.depth-note {
  margin: -8px 0 0;
  color: var(--muted);
  font-size: 0.72rem;
  line-height: 1.45;
}
.stage {
  min-height: 620px;
  position: relative;
  overflow: hidden;
}
#anchorScene {
  width: 100%;
  height: 620px;
  display: block;
}
.legend {
  position: absolute;
  top: 16px;
  left: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  color: var(--muted);
  font-size: 0.72rem;
  pointer-events: none;
}
.legend-item {
  display: flex;
  align-items: center;
  gap: 7px;
}
.swatch {
  width: 20px;
  height: 3px;
  border-radius: 999px;
  background: var(--c);
}
@media (max-width: 780px) {
  .app {
    padding: 15px;
  }
  .layout {
    grid-template-columns: 1fr;
  }
  .stage {
    min-height: 500px;
  }
  #anchorScene {
    height: 500px;
  }
}
@media (max-width: 480px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }
}