:root {
  --ink: #06131d;
  --ink-2: #0b1f2b;
  --ink-3: #163545;
  --paper: #f2efe4;
  --paper-2: #ded9c9;
  --oxygen: #ff6a3d;
  --oxygen-soft: #ffb59d;
  --water: #69d7e7;
  --salt: #d5ef6f;
  --redox: #d7a8ff;
  --white: #fffdf7;
  --muted: #9fb1b8;
  --line: rgba(255,255,255,.16);
  --max: 1440px;
  --header-h: 68px;
  --radius: 24px;
  --font-sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --font-serif: Iowan Old Style, Baskerville, "Times New Roman", serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--ink); }
body {
  margin: 0;
  background: var(--ink);
  color: var(--white);
  font-family: var(--font-sans);
  font-size: 18px;
  line-height: 1.55;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}
button, input, select { font: inherit; }
a { color: inherit; }
svg { display: block; }

.skip-link {
  position: fixed;
  z-index: 1000;
  left: 16px;
  top: 10px;
  padding: 10px 14px;
  background: var(--paper);
  color: var(--ink);
  transform: translateY(-150%);
  border-radius: 6px;
}
.skip-link:focus { transform: none; }

.site-header {
  position: fixed;
  z-index: 100;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-h);
  display: grid;
  grid-template-columns: 46px 1fr 46px;
  align-items: center;
  gap: 24px;
  padding: 0 clamp(18px, 3.2vw, 54px);
  color: var(--white);
  background: linear-gradient(180deg, rgba(3,13,20,.82), rgba(3,13,20,.38) 70%, transparent);
  pointer-events: none;
}
.site-header a { pointer-events: auto; }
.brand, .language {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255,255,255,.35);
  border-radius: 50%;
  text-decoration: none;
  font: 700 13px/1 var(--font-mono);
  letter-spacing: .08em;
  background: rgba(6,19,29,.3);
  backdrop-filter: blur(12px);
}
.language { justify-self: end; }
.site-header nav {
  display: flex;
  justify-content: center;
  gap: clamp(20px, 4vw, 56px);
}
.site-header nav a {
  font: 650 12px/1 var(--font-mono);
  letter-spacing: .12em;
  text-transform: uppercase;
  text-decoration: none;
  opacity: .78;
}
.site-header a:hover, .site-header a:focus-visible { opacity: 1; border-color: var(--oxygen); }

.hero {
  position: relative;
  min-height: 100svh;
  display: grid;
  place-items: center;
  overflow: hidden;
  padding: calc(var(--header-h) + 64px) clamp(20px, 5vw, 80px) 100px;
  background:
    radial-gradient(circle at 72% 22%, rgba(91,215,236,.21), transparent 27%),
    linear-gradient(154deg, #0c2c3b 0%, #071824 44%, #040a11 100%);
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  opacity: .24;
  background-image:
    linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: linear-gradient(to bottom, black, transparent 86%);
}
.hero-grain {
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .13;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 180 180' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.82' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.55'/%3E%3C/svg%3E");
  mix-blend-mode: soft-light;
}
.hero-grid {
  position: relative;
  z-index: 2;
  width: min(var(--max), 100%);
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(320px, .68fr);
  gap: clamp(50px, 8vw, 140px);
  align-items: center;
}
.eyebrow, .section-kicker {
  margin: 0 0 24px;
  color: var(--water);
  font: 700 12px/1.3 var(--font-mono);
  letter-spacing: .16em;
  text-transform: uppercase;
}
.hero h1 {
  max-width: 980px;
  margin: 0;
  font-size: clamp(48px, 7.8vw, 126px);
  line-height: .88;
  letter-spacing: -.067em;
  font-weight: 760;
}
.hero h1 span { display: block; }
.hero h1 strong {
  display: block;
  margin: .05em 0 .07em;
  color: var(--oxygen);
  font: 800 clamp(96px, 18vw, 280px)/.78 var(--font-sans);
  letter-spacing: -.095em;
  text-shadow: 0 0 70px rgba(255,106,61,.14);
}
.hero-post { max-width: 760px; }
.hero-deck {
  max-width: 760px;
  margin: 42px 0 0;
  color: #dbe6e8;
  font: 400 clamp(20px, 2.2vw, 30px)/1.38 var(--font-serif);
}
.hero-actions {
  margin-top: 42px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 24px 30px;
}
.primary-action {
  display: inline-flex;
  align-items: center;
  gap: 28px;
  padding: 16px 20px 16px 24px;
  border-radius: 999px;
  color: var(--ink);
  background: var(--oxygen);
  text-decoration: none;
  font-weight: 760;
  box-shadow: 0 14px 50px rgba(0,0,0,.28);
}
.primary-action span:last-child {
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: rgba(6,19,29,.14);
}
.primary-action:hover, .primary-action:focus-visible { transform: translateY(-2px); background: #ff7d55; }
.hero-actions p {
  margin: 0;
  color: var(--muted);
  font: 600 12px/1.45 var(--font-mono);
  letter-spacing: .05em;
  text-transform: uppercase;
}
.hero-instrument {
  position: relative;
  justify-self: end;
  width: min(100%, 430px);
  aspect-ratio: .57;
  padding: 18px;
  color: var(--ink);
  background: var(--paper);
  border-radius: 8px;
  box-shadow: 0 35px 100px rgba(0,0,0,.45), inset 0 0 0 1px rgba(0,0,0,.15);
  transform: rotate(1.4deg);
}
.hero-instrument::before, .recorder-panel::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .23;
  background: repeating-linear-gradient(0deg, transparent 0 3px, rgba(10,25,31,.045) 3px 4px);
}
.hero-instrument-top, .hero-instrument-bottom {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font: 700 11px/1 var(--font-mono);
  letter-spacing: .12em;
}
.hero-instrument-top { padding-bottom: 12px; border-bottom: 2px solid var(--ink); }
.hero-instrument-top span:first-child { color: #b62f0b; font-size: 18px; }
.hero-instrument svg { width: 100%; height: calc(100% - 56px); }
.hero-grid-lines line { stroke: rgba(6,19,29,.16); stroke-width: 1; }
.hero-profile-line { fill: none; stroke: #d64520; stroke-width: 4; stroke-linecap: round; stroke-linejoin: round; }
.hero-profile-peak { fill: var(--paper); stroke: #d64520; stroke-width: 4; }
.hero-profile-100 { stroke: #06131d; stroke-width: 1.5; stroke-dasharray: 6 6; }
.hero-profile-label { fill: #06131d; font: 700 12px var(--font-mono); }
.hero-instrument-bottom { border-top: 1px solid rgba(6,19,29,.3); padding-top: 12px; }
.surface-line {
  position: absolute;
  z-index: 2;
  bottom: 0;
  left: 0;
  right: 0;
  height: 34px;
  overflow: hidden;
}
.surface-line::before, .surface-line::after, .surface-line span {
  content: "";
  position: absolute;
  left: -5%;
  width: 110%;
  height: 24px;
  border: 1px solid rgba(105,215,231,.36);
  border-radius: 50%;
}
.surface-line::before { top: 10px; }
.surface-line::after { top: 18px; opacity: .55; }
.surface-line span { top: 2px; opacity: .24; }

.dive-lead {
  min-height: 76svh;
  display: grid;
  align-content: center;
  justify-items: center;
  text-align: center;
  padding: 120px 24px;
  background: var(--paper);
  color: var(--ink);
}
.dive-lead .section-kicker { color: #28758a; }
.dive-lead h2, .moving-line h2, .contrast h2, .explorer h2, .why h2, .method h2 {
  margin: 0;
  font-size: clamp(48px, 7vw, 112px);
  line-height: .94;
  letter-spacing: -.06em;
}
.dive-lead > p:last-child {
  max-width: 780px;
  margin: 32px auto 0;
  font: 400 clamp(20px, 2.1vw, 30px)/1.45 var(--font-serif);
}

.dive {
  position: relative;
  height: calc(100vh + 7000px);
  min-height: 7800px;
  background: #06131d;
}
.dive-stage {
  --dive-bg: #153f50;
  position: sticky;
  top: 0;
  height: 100svh;
  min-height: 640px;
  overflow: hidden;
  display: grid;
  grid-template-rows: 36px minmax(0, 1fr) auto;
  padding: calc(var(--header-h) + 12px) clamp(18px, 3.2vw, 52px) 22px;
  background: var(--dive-bg);
  transition: background-color .12s linear;
  isolation: isolate;
}
.water-light {
  position: absolute;
  z-index: -2;
  inset: 0;
  background:
    radial-gradient(ellipse at 50% -10%, rgba(121,231,246,.35), transparent 46%),
    linear-gradient(to bottom, rgba(54,145,166,.16), transparent 34%);
  opacity: var(--surface-light, 1);
  transition: opacity .15s linear;
}
.particulate {
  position: absolute;
  z-index: -1;
  inset: 0;
  opacity: .23;
  background-image:
    radial-gradient(circle at 12% 16%, rgba(255,255,255,.6) 0 1px, transparent 1.7px),
    radial-gradient(circle at 68% 28%, rgba(255,255,255,.45) 0 1px, transparent 1.8px),
    radial-gradient(circle at 82% 62%, rgba(255,255,255,.32) 0 1px, transparent 1.6px),
    radial-gradient(circle at 32% 76%, rgba(255,255,255,.35) 0 1px, transparent 1.8px);
  background-size: 190px 210px, 260px 240px, 230px 280px, 310px 260px;
  transform: translateY(calc(var(--depth-progress, 0) * -160px));
}
.dive-headerline {
  height: auto;
  display: flex;
  justify-content: space-between;
  align-items: start;
  border-top: 1px solid rgba(255,255,255,.38);
  padding-top: 10px;
  color: rgba(255,255,255,.72);
  font: 650 11px/1 var(--font-mono);
  letter-spacing: .12em;
}
.dive-layout {
  height: auto;
  min-height: 0;
  max-width: 1700px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(300px, .86fr) minmax(150px, .42fr) minmax(360px, .84fr);
  gap: clamp(18px, 3vw, 52px);
  align-items: stretch;
}
.dive-copy-panel {
  align-self: center;
  min-width: 0;
  min-height: 0;
  padding: 18px 0;
}
.dive-chapter {
  min-height: 3.2em;
  margin: 0 0 30px;
  max-width: 610px;
  color: var(--white);
  font: 500 clamp(25px, 3vw, 48px)/1.12 var(--font-serif);
  text-wrap: balance;
  transition: font-size .18s ease;
}
.dive-chapter.is-long { font-size: clamp(22px, 2.4vw, 38px); }
.dive-chapter.is-very-long { font-size: clamp(20px, 2.05vw, 32px); }
.depth-display {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: end;
  gap: 10px;
  padding: 18px 0 14px;
  border-top: 1px solid rgba(255,255,255,.35);
  border-bottom: 1px solid rgba(255,255,255,.18);
}
.readout-label, .readouts span {
  font: 650 10px/1.2 var(--font-mono);
  letter-spacing: .13em;
  color: rgba(255,255,255,.68);
}
.term-help,
button.term-help {
  -webkit-appearance: none;
  appearance: none;
  margin: 0;
  border: 0;
  border-radius: 0;
  padding: 0;
  color: inherit;
  background: transparent;
  box-shadow: none;
  font: inherit;
  line-height: inherit;
  cursor: help;
}
button.term-help::-moz-focus-inner { border: 0; padding: 0; }
.term-help:focus-visible {
  outline: 2px solid var(--redox);
  outline-offset: 3px;
  border-radius: 3px;
}
.term-help-inline {
  color: inherit;
  text-decoration: underline;
  text-decoration-style: dotted;
  text-underline-offset: .14em;
}
.term-help-inline:hover,
.term-help-inline:focus-visible,
.term-help-readout:hover,
.term-help-readout:focus-visible {
  color: var(--redox);
}
.term-help-readout {
  display: inline-block;
  width: fit-content;
  justify-self: start;
  text-align: left;
  font: 650 10px/1.2 var(--font-mono);
  letter-spacing: .13em;
  color: rgba(255,255,255,.68);
}
.term-tooltip {
  position: absolute;
  z-index: 30;
  box-sizing: border-box;
  width: max-content;
  max-width: min(290px, calc(100vw - 24px));
  padding: 10px 12px;
  color: rgba(255,255,255,.9);
  background: rgba(6,19,29,.98);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 4px;
  box-shadow: 0 8px 22px rgba(0,0,0,.24);
  font: 500 12px/1.45 var(--font-sans);
  pointer-events: none;
}
.term-tooltip::after {
  content: '';
  position: absolute;
  left: var(--tip-x, 18px);
  width: 7px;
  height: 7px;
  background: rgba(6,19,29,.98);
  border: 1px solid rgba(255,255,255,.25);
  transform: translateX(-50%) rotate(45deg);
}
.term-tooltip[data-placement="below"]::after {
  top: -4px;
  border-right: 0;
  border-bottom: 0;
}
.term-tooltip[data-placement="above"]::after {
  bottom: -4px;
  border-left: 0;
  border-top: 0;
}
.term-tooltip[hidden] { display: none; }
.depth-display strong {
  font: 730 clamp(72px, 8.8vw, 150px)/.75 var(--font-sans);
  letter-spacing: -.08em;
  font-variant-numeric: tabular-nums;
}
.depth-display > span:last-child { font: 700 22px/1 var(--font-mono); padding-bottom: 5px; }
.readouts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 20px;
  background: rgba(255,255,255,.12);
  border: 1px solid rgba(255,255,255,.12);
}
.readouts > div {
  min-height: 88px;
  display: grid;
  grid-template-columns: 1fr auto;
  align-content: space-between;
  padding: 12px;
  background: rgba(3,13,20,.42);
}
.readouts strong {
  align-self: end;
  color: var(--white);
  font: 700 clamp(20px, 2vw, 32px)/1 var(--font-mono);
  letter-spacing: -.05em;
  font-variant-numeric: tabular-nums;
}
.readouts small { align-self: end; color: rgba(255,255,255,.58); font: 600 10px/1 var(--font-mono); }
.readouts > div:first-child strong { color: var(--oxygen); }
.readouts > div:nth-child(4) strong { color: var(--salt); }
.readouts > div:last-child strong { color: var(--redox); }

.sonde-shaft {
  position: relative;
  overflow: hidden;
  border-left: 1px solid rgba(255,255,255,.18);
  border-right: 1px solid rgba(255,255,255,.18);
  background: linear-gradient(90deg, transparent, rgba(0,0,0,.13) 50%, transparent);
}
.cable {
  position: absolute;
  top: -10px;
  bottom: 47%;
  left: 50%;
  width: 2px;
  background: linear-gradient(#d8e7e7, #6b858d);
  box-shadow: 0 0 10px rgba(255,255,255,.24);
}
.sonde {
  position: absolute;
  z-index: 3;
  left: 50%;
  top: 53%;
  width: 48px;
  height: 108px;
  transform: translate(-50%, -50%);
  border: 2px solid #dbe8e8;
  border-radius: 20px 20px 9px 9px;
  background: linear-gradient(90deg, #70878e, #e2eded 45%, #657c84);
  box-shadow: 0 12px 24px rgba(0,0,0,.38);
}
.sonde::before {
  content: "";
  position: absolute;
  left: 50%; top: -13px;
  width: 18px; height: 16px;
  transform: translateX(-50%);
  border: 2px solid #dbe8e8;
  border-bottom: 0;
  border-radius: 8px 8px 0 0;
}
.sonde span, .sonde i, .sonde b { position: absolute; left: 8px; right: 8px; height: 4px; border-radius: 3px; background: #163545; }
.sonde span { top: 28px; }.sonde i { top: 49px; }.sonde b { top: 70px; }
.sonde-wave {
  position: absolute;
  z-index: 1;
  left: 50%; top: 53%;
  width: 90px; height: 90px;
  border: 1px solid rgba(105,215,231,.5);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  animation: ping 2.6s ease-out infinite;
}
.wave-two { animation-delay: 1.3s; }
@keyframes ping { from { width: 50px; height: 50px; opacity: .65; } to { width: 190px; height: 190px; opacity: 0; } }
.shaft-scale {
  position: absolute;
  inset: 0;
  font: 600 10px/1 var(--font-mono);
  color: rgba(255,255,255,.42);
}
.shaft-scale span {
  position: absolute;
  left: 8px;
  right: 8px;
  border-top: 1px solid rgba(255,255,255,.17);
  padding-top: 4px;
}

.recorder-panel {
  position: relative;
  min-height: 0;
  margin: 6px 0;
  overflow: hidden;
  color: var(--ink);
  background: var(--paper);
  border-radius: 8px;
  box-shadow: 0 18px 65px rgba(0,0,0,.28);
}
.recorder-head {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: space-between;
  padding: 13px 16px 10px;
  border-bottom: 2px solid var(--ink);
  font: 700 10px/1.2 var(--font-mono);
  letter-spacing: .08em;
}
.recorder-head span:last-child { font-weight: 500; opacity: .6; text-transform: none; letter-spacing: 0; }
#dive-recorder { position: relative; z-index: 2; width: 100%; height: calc(100% - 68px); }
.recorder-grid line { stroke: rgba(6,19,29,.16); stroke-width: 1; }
.recorder-grid line.major { stroke: rgba(6,19,29,.32); }
.recorder-trace { fill: none; stroke: #d64520; stroke-width: 4; vector-effect: non-scaling-stroke; stroke-linecap: round; stroke-linejoin: round; }
.recorder-cursor { stroke: var(--ink); stroke-width: 1.5; stroke-dasharray: 6 5; }
.recorder-dot { fill: var(--paper); stroke: #d64520; stroke-width: 4; }
.recorder-labels text { fill: var(--ink); font: 700 12px var(--font-mono); }
.recorder-axis {
  position: absolute;
  z-index: 3;
  bottom: 8px;
  left: 16px;
  right: 16px;
  display: flex;
  justify-content: space-between;
  border-top: 1px solid rgba(6,19,29,.28);
  padding-top: 8px;
  font: 650 9px/1 var(--font-mono);
}
.dive-control {
  max-width: 1700px;
  width: min(100%, 1700px);
  height: 64px;
  margin: 10px auto 0;
  display: grid;
  align-content: center;
  padding: 0 4px;
}
.dive-control label, .inspect-control label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  color: rgba(255,255,255,.7);
  font: 650 10px/1 var(--font-mono);
  letter-spacing: .1em;
}
.dive-control output, .inspect-control output { color: var(--white); font-size: 12px; }
input[type="range"] {
  width: 100%;
  height: 18px;
  margin: 0;
  accent-color: var(--oxygen);
  cursor: grab;
}
input[type="range"]:active { cursor: grabbing; }

.moving-line {
  position: relative;
  min-height: 100svh;
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(360px, .75fr);
  align-items: center;
  gap: 8vw;
  padding: 120px clamp(22px, 6vw, 100px);
  color: var(--ink);
  background: var(--oxygen);
  overflow: hidden;
}
.moving-number {
  min-width: 0;
  color: rgba(6,19,29,.94);
  font: 800 clamp(120px, 18vw, 420px)/.72 var(--font-sans);
  letter-spacing: -.11em;
  white-space: nowrap;
  transform: translateX(-.04em);
}
.moving-number span { display: inline-block; margin: 0 .02em; color: rgba(6,19,29,.3); }
.moving-copy { position: relative; z-index: 2; max-width: 650px; }
.moving-copy .section-kicker { color: rgba(6,19,29,.65); }
.moving-copy h2 { font-size: clamp(54px, 7vw, 112px); }
.big-range { margin: 34px 0 20px; font: 800 clamp(52px, 7vw, 105px)/1 var(--font-mono); letter-spacing: -.07em; }
.moving-copy > p:not(.section-kicker):not(.big-range) { font: 480 clamp(20px, 1.8vw, 28px)/1.42 var(--font-serif); }
.moving-copy .fine-note { opacity: .68; font-size: 17px !important; }

.contrast {
  min-height: 84svh;
  display: grid;
  grid-template-columns: minmax(0, .85fr) minmax(460px, 1.15fr);
  gap: clamp(50px, 8vw, 140px);
  align-items: center;
  padding: 110px clamp(22px, 6vw, 100px);
  background: #0a1b27;
}
.contrast-copy { max-width: 720px; }
.contrast-copy h2 { font-size: clamp(52px, 7vw, 116px); }
.contrast-copy > p:last-child { max-width: 650px; margin-top: 34px; color: #c8d7dc; font: 400 clamp(20px, 1.8vw, 28px)/1.48 var(--font-serif); }
.contrast-meter { display: grid; gap: 28px; }
.meter-row span { display: block; margin-bottom: 10px; font: 700 13px/1 var(--font-mono); }
.meter-row i { position: relative; display: block; width: 100%; height: clamp(42px, 6vw, 90px); background: rgba(255,255,255,.08); overflow: hidden; }
.meter-row i::after { content: ""; display: block; width: var(--fill); height: 100%; background: var(--oxygen); }
.meter-row.faint i::after { min-width: 5px; opacity: .6; }
.meter-row.bright i::after { background: linear-gradient(90deg, var(--oxygen), #ffb49b); }
.meter-scale { display: flex; justify-content: space-between; border-top: 1px solid rgba(255,255,255,.25); padding-top: 10px; color: var(--muted); font: 600 10px/1 var(--font-mono); }

.explorer {
  padding: 130px clamp(16px, 4vw, 72px) 150px;
  color: var(--ink);
  background: var(--paper);
}
.explorer-heading { max-width: 1100px; margin: 0 auto 68px; text-align: center; }
.explorer-heading .section-kicker, .method .section-kicker { color: #28758a; }
.explorer-heading > p:last-child { max-width: 850px; margin: 30px auto 0; font: 400 clamp(19px, 1.7vw, 26px)/1.48 var(--font-serif); }
.explorer-grid {
  max-width: 1600px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(360px, .8fr) minmax(570px, 1.2fr);
  gap: 24px;
  align-items: stretch;
}
.map-card, .profile-card {
  min-width: 0;
  border: 1px solid rgba(6,19,29,.24);
  background: #e9e4d6;
  box-shadow: 0 20px 60px rgba(6,19,29,.08);
}
.map-card { display: grid; grid-template-rows: 1fr auto; }
.map-frame {
  position: relative;
  min-height: 620px;
  overflow: hidden;
  background: #0e3343;
}
#map-base { width: 100%; height: 100%; }
.map-sea-grid { stroke: rgba(255,255,255,.08); stroke-width: 1; }
.map-land { fill: #d8d1be; stroke: #06131d; stroke-width: 3; }
.map-coast { fill: none; stroke: #06131d; stroke-width: 3; }
.map-points { position: absolute; inset: 0; }
.map-point {
  --threshold: .5;
  position: absolute;
  width: 30px;
  height: 30px;
  transform: translate(-50%, -50%);
  border: 2px solid var(--paper);
  border-radius: 50%;
  background: hsl(calc(22 + var(--threshold) * 155) 88% 57%);
  color: #06131d;
  font: 800 9px/1 var(--font-mono);
  box-shadow: 0 3px 12px rgba(0,0,0,.38);
  cursor: pointer;
}
.map-point.no-threshold { background: transparent; color: var(--paper); }
.map-point:hover, .map-point:focus-visible { z-index: 5; transform: translate(-50%, -50%) scale(1.35); outline: 3px solid rgba(255,255,255,.55); outline-offset: 2px; }
.map-point.active { z-index: 4; transform: translate(-50%, -50%) scale(1.25); border-color: var(--oxygen); box-shadow: 0 0 0 5px rgba(255,106,61,.22), 0 4px 14px rgba(0,0,0,.45); }
.map-point.compared { z-index: 3; border-style: double; border-width: 4px; border-color: var(--salt); }
.map-label { position: absolute; pointer-events: none; color: rgba(255,255,255,.55); font: 700 10px/1 var(--font-mono); letter-spacing: .12em; }
.map-label.black-sea { top: 14%; left: 34%; font-size: 13px; }
.map-label.istanbul { bottom: 9%; left: 44%; color: #06131d; }
.map-label.bosphorus { bottom: 16%; left: 31%; color: #06131d; transform: rotate(-65deg); }
.map-legend { padding: 18px 20px 20px; border-top: 1px solid rgba(6,19,29,.22); }
.map-legend p { margin: 0 0 10px; font: 650 11px/1.35 var(--font-mono); }
.legend-gradient { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 10px; color: rgba(6,19,29,.72); font: 600 10px/1 var(--font-mono); }
.legend-gradient i { height: 10px; background: linear-gradient(90deg, hsl(22 88% 57%), hsl(177 88% 57%)); }
.hollow-key { display: flex; align-items: center; gap: 8px; margin-top: 13px !important; color: rgba(6,19,29,.64); font-weight: 500 !important; }
.hollow-key i { width: 14px; height: 14px; border: 2px solid #0e3343; border-radius: 50%; }

.profile-card { padding: 22px; background: var(--white); }
.profile-controls {
  display: grid;
  grid-template-columns: minmax(200px, 1fr) auto minmax(200px, 1fr) auto;
  gap: 12px;
  align-items: end;
}
.profile-controls label:not(.compare-toggle), .view-toggle { display: grid; gap: 6px; margin: 0; }
.profile-controls label > span, .view-toggle legend {
  color: rgba(6,19,29,.68);
  font: 700 9px/1 var(--font-mono);
  letter-spacing: .1em;
}
select {
  width: 100%;
  min-height: 44px;
  padding: 7px 34px 7px 10px;
  border: 1px solid rgba(6,19,29,.35);
  border-radius: 0;
  color: var(--ink);
  background: var(--paper);
  font: 650 11px/1.3 var(--font-mono);
}
select:focus-visible, button:focus-visible, input:focus-visible, a:focus-visible { outline: 3px solid var(--oxygen); outline-offset: 3px; }
.compare-toggle { display: flex; align-items: center; gap: 7px; height: 44px; padding: 0 10px; border: 1px solid rgba(6,19,29,.35); background: var(--paper); cursor: pointer; }
.compare-toggle input { accent-color: var(--oxygen); }
.profile-b-control[aria-disabled="true"] { opacity: .42; }
.view-toggle { padding: 0; border: 0; }
.view-toggle > div { display: flex; }
.view-toggle button { min-height: 44px; padding: 0 10px; border: 1px solid rgba(6,19,29,.35); background: var(--paper); color: var(--ink); font: 650 10px/1 var(--font-mono); cursor: pointer; }
.view-toggle button + button { border-left: 0; }
.view-toggle button[aria-pressed="true"] { background: var(--ink); color: var(--white); }
.profile-metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin: 20px 0 6px;
  background: rgba(6,19,29,.18);
  border: 1px solid rgba(6,19,29,.18);
}
.profile-metrics > div { min-height: 92px; display: grid; align-content: space-between; padding: 11px; background: var(--paper); }
.profile-metrics span { color: rgba(6,19,29,.65); font: 700 9px/1.2 var(--font-mono); letter-spacing: .06em; }
.profile-metrics strong { font: 800 clamp(20px, 2.3vw, 34px)/1 var(--font-mono); letter-spacing: -.06em; font-variant-numeric: tabular-nums; }
.profile-metrics small { color: rgba(6,19,29,.62); font: 600 9px/1.25 var(--font-mono); }
.profile-chart-wrap { position: relative; min-height: 500px; margin-top: 8px; background: #f7f4eb; border: 1px solid rgba(6,19,29,.15); }
#profile-chart { width: 100%; height: 100%; min-height: 500px; touch-action: none; }
.chart-grid line { stroke: rgba(6,19,29,.12); stroke-width: 1; }
.chart-grid line.major { stroke: rgba(6,19,29,.28); }
.chart-axis-labels text, .chart-annotation text { fill: var(--ink); font: 650 11px var(--font-mono); }
.chart-axis-labels text.muted { fill: rgba(6,19,29,.55); font-size: 10px; }
.profile-line { fill: none; stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.main-line { stroke: #d64520; stroke-width: 4; }
.compare-line { stroke: #54710d; stroke-width: 3; stroke-dasharray: 8 5; }
.profile-threshold-line { stroke: rgba(6,19,29,.5); stroke-width: 1.5; stroke-dasharray: 4 5; }
.profile-crosshair { stroke: var(--ink); stroke-width: 1.5; stroke-dasharray: 5 5; }
.profile-point.main-point { fill: var(--white); stroke: #d64520; stroke-width: 4; }
.profile-point.compare-point { fill: var(--white); stroke: #54710d; stroke-width: 3; }
.chart-tooltip {
  position: absolute;
  z-index: 5;
  min-width: 190px;
  padding: 10px 12px;
  pointer-events: none;
  color: var(--white);
  background: rgba(6,19,29,.94);
  box-shadow: 0 8px 22px rgba(0,0,0,.2);
  font: 600 11px/1.45 var(--font-mono);
}
.chart-tooltip strong { color: var(--oxygen); }
.chart-note { margin: 8px 0 14px; color: rgba(6,19,29,.62); font: 500 10px/1.4 var(--font-mono); }
.inspect-control { padding-top: 10px; border-top: 1px solid rgba(6,19,29,.2); }
.inspect-control label { color: rgba(6,19,29,.62); }
.inspect-control output { color: var(--ink); }
.presets {
  max-width: 1600px;
  margin: 22px auto 0;
  display: grid;
  grid-template-columns: 1fr repeat(3, minmax(180px, auto));
  gap: 8px;
  align-items: stretch;
}
.presets > p { display: flex; align-items: center; margin: 0; padding: 0 12px; font: 700 10px/1.2 var(--font-mono); text-transform: uppercase; letter-spacing: .08em; }
.presets button { display: flex; align-items: center; gap: 10px; min-height: 50px; padding: 8px 14px; border: 1px solid rgba(6,19,29,.3); background: transparent; color: var(--ink); font: 700 11px/1.2 var(--font-mono); cursor: pointer; }
.presets button span { width: 27px; height: 27px; display: grid; place-items: center; border-radius: 50%; color: var(--white); background: var(--ink); }
.presets button:hover { background: var(--oxygen); }

.why {
  display: grid;
  grid-template-columns: minmax(320px, .82fr) minmax(420px, 1.18fr);
  gap: 24px 7vw;
  padding: 130px clamp(22px, 6vw, 100px);
  background: #0b2532;
}
.why-copy { max-width: 750px; align-self: center; }
.why-copy h2 { font-size: clamp(58px, 8vw, 128px); }
.why-copy > p:last-child { margin-top: 34px; color: #c8d7dc; font: 400 clamp(20px, 1.8vw, 28px)/1.48 var(--font-serif); }
.layers { display: grid; min-height: 640px; border: 1px solid rgba(255,255,255,.22); }
.layer { position: relative; display: flex; flex-direction: column; justify-content: flex-end; padding: 30px; overflow: hidden; }
.layer::before { content: ""; position: absolute; inset: 0; opacity: .4; background-image: radial-gradient(circle at 30% 30%, rgba(255,255,255,.42) 0 1px, transparent 1.5px); background-size: 50px 50px; }
.layer span, .layer small { position: relative; z-index: 2; }
.layer span { font: 800 clamp(42px, 6vw, 86px)/.9 var(--font-mono); letter-spacing: -.07em; }
.layer small { margin-top: 10px; font: 650 11px/1 var(--font-mono); letter-spacing: .1em; text-transform: uppercase; }
.layer.surface { min-height: 30%; color: var(--ink); background: #84dce5; }
.layer.hundred { min-height: 28%; color: var(--white); background: #216679; }
.layer.deep { min-height: 42%; color: var(--white); background: #06131d; }
.redox-note {
  grid-column: 1 / -1;
  display: grid;
  grid-template-columns: minmax(260px, .55fr) minmax(400px, 1.45fr);
  gap: 40px;
  margin-top: 34px;
  padding-top: 28px;
  border-top: 1px solid rgba(255,255,255,.25);
}
.redox-note h3 { margin: 0; color: var(--redox); font-size: clamp(28px, 3vw, 46px); line-height: 1; letter-spacing: -.04em; }
.redox-note p { max-width: 880px; margin: 0; color: #c8d7dc; font: 400 19px/1.55 var(--font-serif); }

.method {
  display: grid;
  grid-template-columns: minmax(300px, .66fr) minmax(500px, 1.34fr);
  gap: 60px 8vw;
  padding: 130px clamp(22px, 6vw, 100px);
  color: var(--ink);
  background: var(--paper);
}
.method h2 { font-size: clamp(52px, 6.6vw, 104px); }
.method-copy { max-width: 900px; }
.method-copy p { margin: 0 0 24px; font: 400 clamp(18px, 1.5vw, 23px)/1.62 var(--font-serif); }
.sources { grid-column: 1 / -1; display: grid; grid-template-columns: repeat(3, 1fr); border-top: 2px solid var(--ink); }
.sources a { display: grid; gap: 22px; min-height: 160px; padding: 22px 18px; border-right: 1px solid rgba(6,19,29,.3); text-decoration: none; }
.sources a:last-child { border-right: 0; }
.sources a span { font: 750 13px/1.3 var(--font-sans); }
.sources a strong { align-self: end; color: rgba(6,19,29,.63); font: 600 11px/1.45 var(--font-mono); }
.sources a:hover, .sources a:focus-visible { background: var(--oxygen); }
.noscript { margin: 0; padding: 20px; color: var(--ink); background: #ffef91; text-align: center; }
footer {
  min-height: 180px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  padding: 40px clamp(22px, 6vw, 100px);
  border-top: 1px solid rgba(255,255,255,.14);
  background: #03090e;
  font: 600 12px/1.4 var(--font-mono);
}
footer a { text-decoration: none; border-bottom: 1px solid rgba(255,255,255,.4); }
footer p { margin: 0; color: var(--muted); }
.page-top { position: absolute; top: 0; left: 0; width: 1px; height: 1px; overflow: hidden; }
.page-top:focus { outline: 2px solid var(--oxygen); outline-offset: 4px; }
.back-to-top {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-width: 44px;
  min-height: 44px;
  padding: 8px 11px;
  border: 1px solid rgba(255,255,255,.28);
  border-radius: 999px;
  background: rgba(242,239,228,.88);
  color: var(--ink);
  font: 700 10px/1 var(--font-mono);
  white-space: nowrap;
}
.no-js .back-to-top { border-bottom: 1px solid rgba(255,255,255,.35); }
.js .back-to-top {
  position: fixed;
  z-index: 90;
  right: clamp(14px, 3vw, 42px);
  bottom: calc(max(16px, env(safe-area-inset-bottom, 0px)) + 80px);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  pointer-events: none;
  transition: opacity .2s ease, transform .2s ease, visibility 0s linear .2s;
}
.js .back-to-top.is-visible {
  opacity: .84;
  visibility: visible;
  transform: none;
  pointer-events: auto;
  transition-delay: 0s;
}
.js .back-to-top.footer-near { bottom: calc(var(--back-footer-offset, 16px) + env(safe-area-inset-bottom, 0px)); }
.back-to-top:hover, .back-to-top:focus-visible { opacity: 1; background: var(--oxygen); border-color: var(--oxygen); }

@media (max-width: 1180px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr) minmax(280px, .48fr); gap: 50px; }
  .hero h1 { font-size: clamp(54px, 8.6vw, 100px); }
  .hero h1 strong { font-size: clamp(110px, 18vw, 220px); }
  .moving-line { grid-template-columns: minmax(0, 1.1fr) minmax(320px, .9fr); gap: 5vw; }
  .moving-number { font-size: clamp(120px, 15vw, 280px); }
  .dive-layout { grid-template-columns: minmax(310px, .9fr) 110px minmax(310px, .8fr); gap: 20px; }
  .readouts { grid-template-columns: repeat(2, 1fr); }
  .explorer-grid { grid-template-columns: 1fr; }
  .map-frame { min-height: 580px; }
  .profile-controls { grid-template-columns: minmax(180px, 1fr) auto minmax(180px, 1fr); }
  .view-toggle { grid-column: 1 / -1; }
  .view-toggle button { min-width: 140px; }
  .presets { grid-template-columns: repeat(3, 1fr); }
  .presets > p { grid-column: 1 / -1; padding: 8px 0; }
}

@media (max-width: 820px) {
  :root { --header-h: 60px; }
  body { font-size: 17px; }
  .site-header { grid-template-columns: 42px 1fr 42px; gap: 12px; padding: 0 14px; }
  .brand, .language { width: 40px; height: 40px; }
  .site-header nav { gap: 16px; }
  .site-header nav a { font-size: 9px; letter-spacing: .07em; }
  .hero { min-height: auto; padding: 120px 20px 86px; }
  .hero-grid { grid-template-columns: 1fr; gap: 56px; }
  .hero h1 { font-size: clamp(48px, 14vw, 82px); line-height: .91; }
  .hero h1 strong { font-size: clamp(104px, 31vw, 190px); margin: .13em 0 .11em; }
  .hero-deck { margin-top: 30px; font-size: 21px; }
  .hero-instrument { justify-self: center; width: min(84vw, 390px); }
  .dive-lead { min-height: 68svh; padding: 100px 22px; }
  .dive-lead h2, .moving-line h2, .contrast h2, .explorer h2, .why h2, .method h2 { font-size: clamp(48px, 14vw, 78px); }
  .dive { height: calc(100vh + 6500px); min-height: 7200px; }
  .dive-stage { padding: calc(var(--header-h) + 8px) 13px 12px; min-height: 600px; }
  .dive-headerline { font-size: 8px; }
  .dive-stage { grid-template-rows: 36px minmax(0, 1fr) auto; }
  .dive-layout { height: auto; grid-template-columns: 1fr; grid-template-rows: auto minmax(0, 1fr); gap: 8px; }
  .dive-copy-panel { align-self: start; padding: 4px 0 0; }
  .dive-chapter { min-height: 2.6em; margin-bottom: 8px; font-size: clamp(20px, 5.8vw, 31px); }
  .dive-chapter.is-long { font-size: clamp(19px, 5vw, 27px); }
  .dive-chapter.is-very-long { font-size: clamp(18px, 4.5vw, 24px); }
  .depth-display { padding: 8px 0; }
  .depth-display strong { font-size: clamp(56px, 18vw, 96px); }
  .readouts { grid-template-columns: repeat(3, 1fr); margin-top: 8px; }
  .readouts > div { min-height: 58px; padding: 7px; }
  .readouts span { font-size: 7px; }
  .readouts strong { font-size: clamp(15px, 4.2vw, 22px); }
  .readouts small { font-size: 7px; }
  .sonde-shaft { display: none; }
  .recorder-panel { min-height: 0; margin: 0; }
  .recorder-head { padding: 8px 10px 7px; font-size: 8px; }
  .recorder-head span:last-child { display: none; }
  #dive-recorder { height: calc(100% - 42px); }
  .recorder-axis { left: 10px; right: 10px; bottom: 5px; font-size: 7px; }
  .dive-control { height: 58px; margin-top: 4px; }
  .moving-line, .contrast { grid-template-columns: 1fr; min-height: auto; padding: 100px 22px; }
  .moving-number { position: absolute; inset: 50% auto auto -8%; transform: translateY(-50%); opacity: .12; font-size: 56vw; }
  .moving-copy { max-width: 640px; }
  .contrast-meter { margin-top: 20px; }
  .explorer { padding: 100px 12px; }
  .explorer-heading { padding: 0 10px; margin-bottom: 44px; }
  .map-frame { min-height: 480px; }
  .profile-card { padding: 12px; }
  .profile-controls { grid-template-columns: 1fr auto; }
  .profile-b-control { grid-column: 1 / -1; }
  .view-toggle { grid-column: 1 / -1; }
  .profile-metrics { grid-template-columns: repeat(2, 1fr); }
  .profile-chart-wrap, #profile-chart { min-height: 470px; }
  .presets { grid-template-columns: 1fr; }
  .presets > p { grid-column: auto; }
  .why { grid-template-columns: 1fr; padding: 100px 22px; }
  .layers { min-height: 560px; }
  .redox-note { grid-template-columns: 1fr; gap: 18px; }
  .method { grid-template-columns: 1fr; padding: 100px 22px; }
  .sources { grid-template-columns: 1fr; }
  .sources a { min-height: 120px; border-right: 0; border-bottom: 1px solid rgba(6,19,29,.3); }
  footer { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 430px) {
  .site-header nav a:nth-child(2) { display: none; }
  .hero { padding-left: 16px; padding-right: 16px; }
  .hero h1 { font-size: 50px; }
  .hero h1 strong { font-size: 119px; }
  .hero-actions { align-items: flex-start; flex-direction: column; }
  .primary-action { width: 100%; justify-content: space-between; }
  .dive-stage { min-height: 620px; }
  .dive-headerline span:last-child { max-width: 56%; text-align: right; }
  .dive-chapter { font-size: 23px; }
  .depth-display strong { font-size: 66px; }
  .readouts > div { min-height: 54px; }
  .readouts strong { font-size: 16px; }
  .map-frame { min-height: 420px; }
  .map-point { width: 27px; height: 27px; font-size: 8px; }
  .profile-controls { grid-template-columns: 1fr; }
  .compare-toggle { width: max-content; }
  .profile-b-control, .view-toggle { grid-column: 1; }
  .profile-metrics strong { font-size: 21px; }
  .profile-chart-wrap, #profile-chart { min-height: 430px; }
  .layers { min-height: 500px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
  .particulate { transform: none; }
  .js .back-to-top { transition: none; }
}

@media (forced-colors: active) {
  .map-point, .sonde, .profile-point, .hero-profile-peak, .recorder-dot { forced-color-adjust: none; }
}