/* ============================================================
   Echo Exploration — abyssal sonar instrument
   ============================================================ */

:root {
  --abyss:        #02050a;
  --abyss-2:      #04080f;
  --ink:          #060b14;
  --echo:         #4fd6c4;   /* desaturated sonar teal */
  --echo-dim:     #2b6f69;
  --echo-faint:   rgba(79, 214, 196, 0.14);
  --beacon:       #e8b14b;   /* amber exit */
  --beacon-soft:  rgba(232, 177, 75, 0.16);
  --bone:         #d7e4e2;
  --mist:         #6f8a88;
  --line:         rgba(79, 214, 196, 0.18);

  --display: 'Major Mono Display', monospace;
  --mono: 'JetBrains Mono', ui-monospace, monospace;

  --ease: cubic-bezier(0.16, 0.84, 0.3, 1);
}

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

html, body {
  height: 100%;
  background: var(--abyss);
  color: var(--bone);
  font-family: var(--mono);
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---- Stage / canvas ------------------------------------------------ */

.stage {
  position: fixed;
  inset: 0;
  display: grid;
  place-items: center;
}

#scene {
  display: block;
  width: 100%;
  height: 100%;
  background: #000;          /* the darkness, honoured literally */
  touch-action: none;
  cursor: crosshair;
}

/* A thin instrument frame + heavy vignette around the void */
.stage::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 4;
  box-shadow:
    inset 0 0 0 1px rgba(79, 214, 196, 0.07),
    inset 0 0 180px 40px rgba(0, 0, 0, 0.9);
  background:
    radial-gradient(120% 120% at 50% 50%, transparent 58%, rgba(0,0,0,0.55) 100%);
}

/* ---- HUD ----------------------------------------------------------- */

.hud {
  position: absolute;
  top: 0; left: 0; right: 0;
  z-index: 6;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 1.1rem clamp(1rem, 4vw, 2.4rem);
  pointer-events: none;
  transition: opacity 0.6s var(--ease);
}
.hud > * { pointer-events: auto; }

.hud__brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-right: auto;
}
.hud__mark {
  width: 13px; height: 13px;
  border-radius: 50%;
  background: var(--echo);
  box-shadow: 0 0 12px var(--echo), 0 0 26px var(--echo-dim);
  animation: beat 2.6s var(--ease) infinite;
}
@keyframes beat {
  0%, 100% { transform: scale(1);   opacity: 1; }
  50%      { transform: scale(0.55); opacity: 0.4; }
}
.hud__title {
  font-family: var(--display);
  font-size: clamp(0.8rem, 2.4vw, 1.05rem);
  letter-spacing: 0.04em;
  color: var(--bone);
}

.hud__stats {
  display: flex;
  gap: clamp(0.8rem, 3vw, 2rem);
}
.stat { text-align: right; }
.stat dt {
  font-size: 0.58rem;
  letter-spacing: 0.34em;
  text-transform: uppercase;
  color: var(--mist);
}
.stat dd {
  font-variant-numeric: tabular-nums;
  font-size: clamp(1rem, 3.4vw, 1.5rem);
  font-weight: 500;
  color: var(--echo);
  text-shadow: 0 0 14px rgba(79, 214, 196, 0.35);
}

.hud__help {
  width: 2.1rem; height: 2.1rem;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: rgba(79, 214, 196, 0.05);
  color: var(--echo);
  font-family: var(--mono);
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.25s var(--ease), transform 0.25s var(--ease);
}
.hud__help:hover { background: rgba(79, 214, 196, 0.16); transform: scale(1.08); }
.hud__help:active { transform: scale(0.94); }

/* ---- Pulse prompt -------------------------------------------------- */

.prompt {
  position: absolute;
  bottom: clamp(1.4rem, 6vh, 3rem);
  left: 50%;
  transform: translateX(-50%);
  z-index: 6;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--mist);
  opacity: 0;
  transition: opacity 0.7s var(--ease);
  pointer-events: none;
}
.prompt.is-on { opacity: 1; animation: promptFade 5.5s var(--ease) forwards; }
@keyframes promptFade { 0%,70% { opacity: 1; } 100% { opacity: 0; } }

kbd {
  font-family: var(--mono);
  font-size: 0.66rem;
  line-height: 1;
  padding: 0.32em 0.5em;
  border-radius: 5px;
  border: 1px solid var(--line);
  background: rgba(79, 214, 196, 0.06);
  color: var(--echo);
  letter-spacing: 0.05em;
}

/* ---- Overlays ------------------------------------------------------ */

.overlay {
  position: absolute;
  inset: 0;
  z-index: 10;
  display: grid;
  place-items: center;
  padding: 1.5rem;
  background:
    radial-gradient(80% 80% at 50% 40%, rgba(8, 18, 24, 0.62), rgba(2, 5, 10, 0.93));
  backdrop-filter: blur(7px) saturate(120%);
  -webkit-backdrop-filter: blur(7px) saturate(120%);
  transition: opacity 0.55s var(--ease), visibility 0.55s var(--ease);
}
.overlay[aria-hidden="true"] {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.panel {
  position: relative;
  width: min(540px, 100%);
  padding: clamp(1.8rem, 5vw, 3.2rem);
  border: 1px solid var(--line);
  border-radius: 18px;
  background:
    linear-gradient(155deg, rgba(10, 22, 28, 0.92), rgba(3, 7, 12, 0.94));
  box-shadow:
    0 40px 120px -30px rgba(0, 0, 0, 0.9),
    inset 0 1px 0 rgba(79, 214, 196, 0.08);
  overflow: hidden;
}
/* faint sonar arcs etched into the panel corner */
.panel::before {
  content: "";
  position: absolute;
  top: -120px; right: -120px;
  width: 300px; height: 300px;
  border-radius: 50%;
  border: 1px solid var(--echo-faint);
  box-shadow:
    0 0 0 26px transparent,
    inset 0 0 0 40px transparent;
  background:
    radial-gradient(circle, transparent 64%, var(--echo-faint) 65%, transparent 66%),
    radial-gradient(circle, transparent 78%, var(--echo-faint) 79%, transparent 80%);
  pointer-events: none;
}

.panel__eyebrow {
  font-size: 0.62rem;
  letter-spacing: 0.4em;
  text-transform: uppercase;
  color: var(--echo-dim);
  margin-bottom: 1.1rem;
}

.panel__title {
  font-family: var(--display);
  font-size: clamp(2.6rem, 11vw, 4.4rem);
  line-height: 0.92;
  letter-spacing: 0.01em;
  color: var(--bone);
  margin-bottom: 1.3rem;
  text-shadow: 0 0 38px rgba(79, 214, 196, 0.22);
}
.panel__title--win { color: var(--echo); text-shadow: 0 0 44px rgba(79, 214, 196, 0.4); }

.panel__lede {
  font-size: 0.9rem;
  font-weight: 300;
  line-height: 1.65;
  color: var(--mist);
  max-width: 42ch;
  margin-bottom: 1.8rem;
}
.panel__lede--win { margin-bottom: 2rem; }

.rules {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.95rem;
  margin-bottom: 2.2rem;
}
.rules li {
  display: grid;
  grid-template-columns: minmax(120px, 0.85fr) 1.4fr;
  gap: 1rem;
  align-items: baseline;
  padding-bottom: 0.9rem;
  border-bottom: 1px solid rgba(79, 214, 196, 0.07);
}
.rules li:last-child { border-bottom: none; padding-bottom: 0; }
.rules__key {
  display: flex;
  flex-wrap: wrap;
  gap: 0.28rem;
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--echo);
}
.rules__key.amber { color: var(--beacon); }
.rules__text {
  font-size: 0.84rem;
  font-weight: 300;
  line-height: 1.5;
  color: var(--bone);
}

/* ---- Buttons ------------------------------------------------------- */

.cta {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--abyss);
  background: var(--echo);
  border: none;
  border-radius: 999px;
  padding: 0.95rem 2.1rem;
  cursor: pointer;
  transition: transform 0.25s var(--ease), box-shadow 0.3s var(--ease), background 0.3s var(--ease);
  box-shadow: 0 0 0 0 rgba(79, 214, 196, 0.5), 0 12px 30px -10px rgba(79, 214, 196, 0.5);
}
.cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 36px 2px rgba(79, 214, 196, 0.45), 0 18px 40px -12px rgba(79, 214, 196, 0.6);
}
.cta:active { transform: translateY(0) scale(0.97); }
.cta:focus-visible { outline: 2px solid var(--bone); outline-offset: 3px; }

/* ---- Scorecard (win) ---------------------------------------------- */

.scorecard {
  display: flex;
  gap: 2.5rem;
  margin-bottom: 1.8rem;
}
.scorecard dt {
  font-size: 0.58rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--mist);
  margin-bottom: 0.4rem;
}
.scorecard dd {
  font-variant-numeric: tabular-nums;
  font-size: clamp(2rem, 8vw, 2.8rem);
  font-weight: 700;
  color: var(--beacon);
  text-shadow: 0 0 26px var(--beacon-soft);
}

/* ---- Reveal animation for the win panel --------------------------- */

.overlay--win .panel { animation: rise 0.7s var(--ease) both; }
@keyframes rise {
  from { transform: translateY(26px) scale(0.97); opacity: 0; }
  to   { transform: translateY(0) scale(1); opacity: 1; }
}

/* ---- Dimmed HUD while overlays are open --------------------------- */

body.is-overlay .hud { opacity: 0.12; }

@media (max-width: 480px) {
  .hud__title { display: none; }
  .rules li { grid-template-columns: 1fr; gap: 0.3rem; }
}

@media (prefers-reduced-motion: reduce) {
  .hud__mark { animation: none; }
  .overlay--win .panel { animation: none; }
}