:root {
  --bg: #02070c;
  --ink: #d6e4e8;
  --dim: rgba(214, 228, 232, .62);
  --faint: rgba(214, 228, 232, .3);
  --hair: rgba(143, 227, 239, .16);
  --accent: #8fe3ef;
  --serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, Georgia, serif;
  --mono: ui-monospace, "SFMono-Regular", "Cascadia Mono", "Cascadia Code", Consolas, "Liberation Mono", monospace;
  --gutter: 16px;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; background: var(--bg); }
body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  color: var(--ink);
  background: radial-gradient(120% 70% at 50% -10%, #06202e 0%, #03111b 38%, var(--bg) 72%) no-repeat, var(--bg);
  font: 16.5px/1.5 var(--serif);
  overflow-x: hidden;
}
[hidden] { display: none !important; }
::selection { background: rgba(143, 227, 239, .28); color: #fff; }
button, input { font: inherit; color: inherit; }
button { cursor: pointer; -webkit-tap-highlight-color: transparent; }
:focus-visible { outline: 1px solid var(--accent); outline-offset: 3px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

.shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  grid-template-areas: "top" "brief" "rig";
  gap: 18px;
  max-width: 1180px;
  margin: 0 auto;
  padding: max(10px, env(safe-area-inset-top)) max(var(--gutter), env(safe-area-inset-right)) max(22px, env(safe-area-inset-bottom)) max(var(--gutter), env(safe-area-inset-left));
}

.top { grid-area: top; display: flex; align-items: center; justify-content: space-between; height: 36px; }
.mark { font: 11px/1 var(--mono); letter-spacing: .42em; color: var(--faint); }

.icon {
  display: inline-grid; place-items: center;
  width: 38px; height: 38px; padding: 0;
  border: 0; border-radius: 50%; background: transparent;
  color: var(--dim);
  transition: color .2s, background-color .2s;
}
.icon:hover { color: var(--ink); background: rgba(143, 227, 239, .06); }
.icon svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; stroke-linejoin: round; }
#sound { margin-right: -8px; }
#sound .on { display: none; }
#sound[aria-pressed="true"] .on { display: inline; }
#sound[aria-pressed="true"] .off { display: none; }
#sound[aria-pressed="true"] { color: var(--accent); }

.brief { grid-area: brief; max-width: 32em; }
.prompt p { margin: 0 0 .45em; text-wrap: pretty; }
.prompt p:first-child { font-style: italic; color: var(--dim); }
.prompt .ask { margin: .85em 0 0; color: #f2f8fa; }

.answer { display: flex; align-items: flex-end; gap: 4px; margin-top: 18px; }
.answer.shake { animation: shake .42s cubic-bezier(.36, .07, .19, .97); }
@keyframes shake {
  20% { transform: translateX(-5px); } 40% { transform: translateX(4px); }
  60% { transform: translateX(-3px); } 80% { transform: translateX(2px); }
}
#guess {
  width: 5.4ch; letter-spacing: .12em; padding: 4px 0 6px; margin-right: 8px;
  border: 0; border-bottom: 1px solid var(--faint); border-radius: 0;
  background: transparent; outline: 0;
  font: 26px/1 var(--mono); text-align: center;
  caret-color: var(--accent);
  transition: border-color .2s;
}
#guess:focus { border-bottom-color: var(--accent); }
#guess { border-bottom-color: var(--dim); }
.hint-toggle { margin-left: auto; margin-right: -8px; font: 14px/1 var(--mono); color: var(--faint); }
.hint-toggle[aria-expanded="true"] { color: var(--accent); }
.hint { margin: 12px 0 0; font-style: italic; color: var(--dim); font-size: .88em; }

.vault { margin-top: 24px; animation: rise 1.1s ease-out both; }
@keyframes rise { from { opacity: 0; transform: translateY(8px); } }
.greet { margin: 0 0 12px; font-style: italic; color: var(--dim); }
.key {
  display: flex; align-items: center; gap: 8px;
  padding: 14px 8px 14px 16px;
  border: 1px solid var(--hair); background: rgba(143, 227, 239, .035);
}
#key {
  flex: 1; min-width: 0;
  font: 500 clamp(13px, 3.9vw, 24px)/1.35 var(--mono);
  letter-spacing: .02em; color: #eafcff;
  overflow-wrap: anywhere; user-select: all;
}
.copy .tick { display: none; }
.copy.done { color: var(--accent); }
.copy.done .tick { display: inline; }
.copy.done .sheet { display: none; }

.rig { grid-area: rig; display: flex; flex-direction: column; min-width: 0; }
.column {
  position: relative;
  height: clamp(360px, 56vh, 620px);
  border: 1px solid var(--hair);
  overflow: hidden;
  touch-action: none;
  cursor: crosshair;
  background: #010307;
  -webkit-user-select: none; user-select: none;
}
#sea { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }

.gauge { position: absolute; top: 0; right: 0; bottom: 0; width: 40px; cursor: ns-resize; outline: 0; }
.gauge:focus-visible { box-shadow: inset 0 0 0 1px var(--accent); }

.bar { display: flex; align-items: center; gap: 16px; padding-top: 12px; }
.depth { display: flex; align-items: baseline; gap: 7px; margin: 0; padding-left: 2px; font-family: var(--mono); }
#metres { font-size: 22px; color: var(--ink); font-variant-numeric: tabular-nums; }
.depth .unit { font-size: 11px; letter-spacing: .2em; color: var(--faint); }
.lamp {
  display: inline-grid; place-items: center;
  margin-left: auto; width: 44px; height: 40px; padding: 0;
  border: 1px solid var(--faint); border-radius: 0; background: transparent;
  color: var(--dim);
  transition: background-color .2s, color .2s, border-color .2s;
}
.lamp svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.4; stroke-linecap: round; }
.lamp .rays { opacity: 0; transition: opacity .2s; }
.lamp[aria-pressed="true"] { color: #ffe9c4; border-color: rgba(255, 233, 196, .5); background: rgba(255, 233, 196, .07); }
.lamp[aria-pressed="true"] circle { fill: rgba(255, 233, 196, .25); }
.lamp[aria-pressed="true"] .rays { opacity: 1; }
.lamp:hover { color: var(--ink); }

.noscript { padding: var(--gutter); font: 13px var(--mono); color: var(--dim); }

@media (min-width: 900px) {
  body { font-size: 21px; }
  .brief { max-width: 30em; }
  .shell {
    grid-template-columns: minmax(0, 1fr) 420px;
    grid-template-areas: "top top" "brief rig";
    column-gap: clamp(48px, 8vw, 128px);
    row-gap: 8px;
    padding-top: 18px;
    padding-left: max(48px, env(safe-area-inset-left));
    padding-right: max(48px, env(safe-area-inset-right));
  }
  .brief { align-self: center; padding-bottom: 40px; }
  .column { height: max(460px, min(calc(100vh - 150px), 780px)); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}