/* ============================================================
   ABYSSAL — descent interface
   Genos (display, Eurostile DNA) + Fragment Mono (instruments)
   ============================================================ */

:root{
  --abyss-0:#02060c;         /* surface navy-black        */
  --abyss-1:#000105;         /* terminal black            */
  --cyan:#40f2ff;            /* bioluminescent accent     */
  --cyan-dim:rgba(64,242,255,.55);
  --cyan-ghost:rgba(64,242,255,.14);
  --amber:#ffb454;           /* hydrothermal accent       */
  --ink:#eaf6f8;
  --ink-dim:rgba(214,235,240,.52);
  --ink-faint:rgba(214,235,240,.28);
  --hairline:rgba(150,200,210,.16);
  --mono:'Fragment Mono',ui-monospace,monospace;
  --disp:'Genos',system-ui,sans-serif;
  --pad:clamp(18px,3.4vw,52px);
}

*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:auto}
html,body{background:var(--abyss-1)}
body{
  color:var(--ink);
  font-family:var(--disp);
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
::selection{background:var(--cyan);color:#001318}

/* ---------- scroll track ---------- */
#track{position:relative;width:1px;pointer-events:none}

/* ---------- ocean canvas + atmosphere ---------- */
#ocean{
  position:fixed;inset:0;width:100vw;height:100vh;height:100dvh;
  display:block;background:var(--abyss-0);z-index:0;
}
#grade{position:fixed;inset:0;z-index:1;pointer-events:none;
  background:linear-gradient(180deg,rgba(1,3,8,.24),rgba(0,0,0,0) 30%,rgba(0,0,0,0) 62%,rgba(0,1,4,.55));
}
#grade::after{ /* depth tint, opacity driven by JS var */
  content:"";position:absolute;inset:0;background:#000208;opacity:var(--depth-tint,0);
}
#vignette{position:fixed;inset:0;z-index:2;pointer-events:none;
  background:radial-gradient(118% 88% at 50% 46%,transparent 58%,rgba(0,2,6,.62) 100%);
}
#grain{position:fixed;inset:-40px;z-index:3;pointer-events:none;opacity:.30;mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='240' height='240'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.82' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.5'/%3E%3C/svg%3E");
  animation:grain 900ms steps(3) infinite;
}
@keyframes grain{
  0%{transform:translate(0,0)}33%{transform:translate(-22px,14px)}66%{transform:translate(14px,-20px)}100%{transform:translate(0,0)}
}

/* ============================================================
   HUD
   ============================================================ */
#hud{position:fixed;inset:0;z-index:6;pointer-events:none;font-family:var(--mono);
  opacity:0;transition:opacity 1.2s ease .2s}
body.ready #hud{opacity:1}

.hud-corner{position:absolute;width:26px;height:26px;border:1px solid var(--cyan-dim);opacity:.8}
.hud-corner.tl{top:14px;left:14px;border-right:0;border-bottom:0}
.hud-corner.tr{top:14px;right:14px;border-left:0;border-bottom:0}
.hud-corner.bl{bottom:14px;left:14px;border-right:0;border-top:0}
.hud-corner.br{bottom:14px;right:14px;border-left:0;border-top:0}

.hud-top{position:absolute;top:0;left:0;right:0;display:flex;justify-content:space-between;align-items:baseline;
  padding:calc(14px + env(safe-area-inset-top)) var(--pad) 12px;
  font-size:11px;letter-spacing:.14em}
.hud-ident{display:flex;gap:18px;align-items:baseline}
.wordmark{font-family:var(--disp);font-weight:300;font-size:21px;letter-spacing:.52em;color:var(--ink)}
.dim{color:var(--ink-dim)}
.hud-mission{display:flex;gap:12px;align-items:center;font-size:10px}
.sep{color:var(--ink-faint)}
.rec{color:var(--ink-dim);display:inline-flex;gap:7px;align-items:center}
.rec i{width:7px;height:7px;border-radius:50%;background:#ff5d5d;display:inline-block;animation:blink 1.6s steps(2) infinite}
@keyframes blink{50%{opacity:.15}}

/* left depth ruler */
.hud-left{position:absolute;top:16vh;bottom:16vh;left:calc(var(--pad) - 6px);width:44px;display:flex}
.ruler{position:relative;width:100%;overflow:hidden;
  -webkit-mask-image:linear-gradient(180deg,transparent,#000 12%,#000 88%,transparent);
          mask-image:linear-gradient(180deg,transparent,#000 12%,#000 88%,transparent)}
.ruler-ticks{position:absolute;left:0;right:0;top:0;will-change:transform;color:var(--ink-faint);font-size:8.5px;letter-spacing:.08em}
.ruler-ticks .tick{position:absolute;left:0;right:0;height:1px;background:var(--hairline)}
.ruler-ticks .tick.major{background:rgba(150,200,210,.34)}
.ruler-ticks .tick span{position:absolute;left:0;top:3px;color:var(--ink-faint)}
.ruler-needle{position:absolute;top:50%;left:-4px;right:0;height:1px;background:var(--cyan);box-shadow:0 0 12px var(--cyan)}
.ruler-needle::before{content:"";position:absolute;left:-2px;top:-3px;border:3.5px solid transparent;border-left-color:var(--cyan)}

/* right readouts */
.hud-right{position:absolute;right:var(--pad);top:50%;transform:translateY(-50%);
  display:flex;flex-direction:column;gap:17px;text-align:right}
.readout label{display:block;font-size:9px;letter-spacing:.26em;color:var(--ink-faint)}
.readout output{display:block;font-size:15px;color:var(--ink);letter-spacing:.06em;margin-top:2px}
.readout output.ok{color:var(--cyan);font-size:11px;letter-spacing:.2em}
.readout small{font-size:8.5px;letter-spacing:.22em;color:var(--ink-faint)}
.depth-readout output{font-size:34px;color:var(--cyan);text-shadow:0 0 18px rgba(64,242,255,.45);letter-spacing:.04em}
.readout.thermal output{color:var(--amber);text-shadow:0 0 14px rgba(255,180,84,.4)}

/* bottom zone tag */
.hud-bottom{position:absolute;left:var(--pad);right:var(--pad);
  bottom:calc(16px + env(safe-area-inset-bottom));
  display:flex;justify-content:space-between;align-items:flex-end}
.zone-tag{display:flex;gap:14px;align-items:center}
#hud-zone-index{font-size:11px;color:var(--cyan);letter-spacing:.2em}
.zone-divider{width:1px;height:30px;background:var(--hairline)}
.zone-name-wrap{display:flex;flex-direction:column;gap:3px}
#hud-zone{font-family:var(--disp);font-weight:300;font-size:19px;letter-spacing:.42em;color:var(--ink)}
#hud-zone-range{font-size:9px;letter-spacing:.24em}
#scroll-cue{display:flex;flex-direction:column;align-items:center;gap:8px;font-size:9px;letter-spacing:.3em;color:var(--ink-dim);
  transition:opacity .6s ease}
#scroll-cue i{width:1px;height:34px;background:linear-gradient(180deg,var(--cyan),transparent);display:block;animation:drop 1.8s ease-in-out infinite}
@keyframes drop{0%{transform:scaleY(.2);transform-origin:top;opacity:0}35%{transform:scaleY(1);opacity:1}100%{transform:scaleY(1);transform-origin:top;opacity:0}}
body.diving #scroll-cue{opacity:0}

/* ============================================================
   NARRATIVE PANELS
   ============================================================ */
.panel{position:fixed;inset:0;z-index:5;display:flex;align-items:center;pointer-events:none;
  opacity:0;visibility:hidden}
.panel .inner{width:min(1120px,calc(100% - 2*var(--pad)) );margin-inline:auto;
  will-change:transform,opacity}
.panel .inner.center{text-align:center}
.panel .inner.left{padding-right:38vw}
.panel .inner.right{text-align:right;padding-left:30vw}
.panel .inner.wide{text-align:center}
@media (min-width:901px){ /* keep narrative clear of HUD instrument columns */
  .panel .inner.right{padding-right:180px}
  .panel .inner.left{padding-left:80px}
  .panel .inner.center,.panel .inner.wide{padding-inline:170px}
}

.kicker{font-family:var(--mono);font-size:10px;letter-spacing:.4em;color:var(--cyan);margin-bottom:26px}
.mega{font-weight:100;font-size:clamp(58px,10.5vw,158px);line-height:.94;letter-spacing:.08em}
.mega .accent{color:var(--cyan)}
.lede{margin-top:30px;font-weight:300;font-size:clamp(17px,1.9vw,24px);letter-spacing:.12em;line-height:1.75;color:var(--ink-dim)}

.zone-eyebrow{font-family:var(--mono);font-size:10.5px;letter-spacing:.34em;color:var(--ink-dim);margin-bottom:22px}
.zone-eyebrow b{color:var(--cyan);font-weight:400;margin-right:10px}
.panel h2{font-weight:200;font-size:clamp(28px,3.6vw,52px);line-height:1.22;letter-spacing:.045em;max-width:21em}
.panel .inner.right h2{margin-left:auto}
.panel .inner.center h2{margin-inline:auto}
.support{margin-top:24px;font-family:var(--mono);font-size:clamp(11px,1.05vw,13.5px);line-height:1.9;letter-spacing:.08em;color:var(--ink-dim);max-width:46em}
.panel .inner.right .support{margin-left:auto}
.panel .inner.center .support,.panel .inner.wide .support{margin-inline:auto}

/* specs grid */
.specs-title{margin-bottom:34px}
.specs{list-style:none;display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--hairline);
  border:1px solid var(--hairline);max-width:980px;margin-inline:auto}
.specs li{background:rgba(1,6,12,.55);backdrop-filter:blur(6px);padding:18px 14px 16px;display:flex;flex-direction:column;gap:8px}
.specs label{font-family:var(--mono);font-size:8.5px;letter-spacing:.24em;color:var(--ink-faint)}
.specs b{font-weight:300;font-size:clamp(15px,1.5vw,21px);letter-spacing:.1em;color:var(--ink)}
.vent-note{color:var(--amber);opacity:.85}

/* offer + CTA */
.offer{font-weight:100;font-size:clamp(44px,7vw,104px);line-height:1.12;letter-spacing:.06em}
.cta-title{font-weight:200;letter-spacing:.08em;margin-bottom:40px}
.manifest-btn{pointer-events:auto;display:inline-block;font-family:var(--mono);font-size:13px;letter-spacing:.42em;text-decoration:none;
  color:var(--cyan);border:1px solid var(--cyan-dim);padding:20px 46px 19px 52px;position:relative;overflow:hidden;
  transition:color .45s ease,border-color .45s ease;background:rgba(2,10,16,.35)}
.manifest-btn::before{content:"";position:absolute;inset:0;background:var(--cyan);transform:translateX(-101%);transition:transform .45s cubic-bezier(.7,0,.2,1);z-index:-1}
.manifest-btn:hover{color:#001318;border-color:var(--cyan)}
.manifest-btn:hover::before{transform:translateX(0)}
.manifest-btn:focus-visible{outline:1px solid var(--cyan);outline-offset:4px}
.fineprint{margin-top:44px;font-family:var(--mono);font-size:9.5px;letter-spacing:.22em;line-height:2.1;color:var(--ink-faint)}

/* ============================================================
   LOADER — pre-dive sequence
   ============================================================ */
#loader{position:fixed;inset:0;z-index:20;background:var(--abyss-1);display:flex;align-items:center;justify-content:center;
  transition:opacity 1s ease,visibility 1s ease}
#loader.done{opacity:0;visibility:hidden}
.loader-box{width:min(430px,84vw);text-align:center}
.loader-wordmark{font-weight:200;font-size:34px;letter-spacing:.62em;padding-left:.62em}
.loader-sub{font-family:var(--mono);font-size:9.5px;letter-spacing:.3em;margin-top:10px}
.loader-bar{height:1px;background:var(--hairline);margin:38px 0 14px;position:relative;overflow:hidden}
.loader-bar i{position:absolute;inset:0;transform-origin:left;transform:scaleX(0);background:var(--cyan);box-shadow:0 0 14px var(--cyan);transition:transform .3s ease}
.loader-status{display:flex;justify-content:space-between;font-family:var(--mono);font-size:9.5px;letter-spacing:.18em;color:var(--ink-dim)}

.noscript{position:fixed;inset:0;z-index:40;background:var(--abyss-1);display:flex;flex-direction:column;gap:18px;align-items:center;justify-content:center;text-align:center;padding:24px}

/* ============================================================
   RESPONSIVE + MOTION SAFETY
   ============================================================ */
@media (max-width:900px){
  .hud-right{top:auto;bottom:calc(96px + env(safe-area-inset-bottom));transform:none}
  .hud-right .readout{display:none}
  .hud-right .depth-readout{display:block}
  .depth-readout output{font-size:26px}
  .hud-left{display:none}
  .panel .inner.left{padding-right:0}
  .panel .inner.right{padding-left:0;text-align:left}
  .panel .inner.right h2,.panel .inner.right .support{margin-left:0}
  .specs{grid-template-columns:repeat(2,1fr)}
  .hud-mission span:first-child{display:none}
  /* condensed mobile depth pill */
  .hud-bottom{align-items:flex-end}
}
@media (max-width:900px){
  .mobile-depth{position:fixed;right:var(--pad);top:calc(52px + env(safe-area-inset-top));
    font-family:var(--mono);text-align:right;pointer-events:none}
}

@media (prefers-reduced-motion:reduce){
  #grain{animation:none}
  #scroll-cue i,.rec i{animation:none}
}

body.static-mode #track{display:none}
body.static-mode .panel{position:relative;inset:auto;opacity:1;visibility:visible;min-height:88vh;padding:8vh 0}
body.static-mode #ocean{position:fixed}