/* ============================================================
   SteroNova — design tokens
   ============================================================ */
:root{
  --ink:#0A1620;
  --ink-soft:#13232E;
  --ink-70:rgba(10,22,32,.70);
  --paper:#F6F7F6;
  --paper-2:#ECEEEC;
  --line:#DCE0DE;
  --line-dark:rgba(255,255,255,.10);
  --slate:#54646B;
  --slate-2:#8A979C;
  --aqua:#0DA890;
  --aqua-b:#3FD9C0;
  --aqua-glow:#7FF4E0;
  --sand:#E8E3D8;

  --maxw:1180px;
  --ease:cubic-bezier(.22,.61,.36,1);
  --ease-soft:cubic-bezier(.4,0,.2,1);
}

*,*::before,*::after{box-sizing:border-box;}
html{ -webkit-text-size-adjust:100%; scroll-behavior:smooth; }
body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:Manrope,"Helvetica Neue",Arial,sans-serif;
  font-weight:400;
  font-size:17px;
  line-height:1.62;
  letter-spacing:-.005em;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  overflow-x:hidden;
}
/* soft page entrance — also masks the webfont swap */
html.js body{opacity:0;transition:opacity .6s var(--ease-soft);}
html.js body.ready{opacity:1;}

img,svg{max-width:100%;display:block;}
a{color:inherit;text-decoration:none;}

/* film-grain + mesh atmosphere */
body::before{
  content:"";position:fixed;inset:0;pointer-events:none;z-index:1;
  opacity:.30;mix-blend-mode:multiply;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)' opacity='.32'/%3E%3C/svg%3E");
}

/* ---------- typography ---------- */
.display{
  font-family:"Instrument Serif",Georgia,serif;
  font-weight:400;
  letter-spacing:-.018em;
  line-height:.98;
}
.display em{font-style:italic;}
.mono{
  font-family:"IBM Plex Mono",ui-monospace,monospace;
  font-size:11px;
  letter-spacing:.20em;
  text-transform:uppercase;
  font-weight:500;
}
.lede{ font-size:clamp(17px,1.35vw,20px); line-height:1.66; color:var(--slate); font-weight:400; }
.wrap{ width:100%; max-width:var(--maxw); margin-inline:auto; padding-inline:24px; position:relative; z-index:2; }

/* eyebrow with tick */
.eyebrow{ display:inline-flex; align-items:center; gap:12px; color:var(--slate-2); }
.eyebrow::before{ content:""; width:26px; height:1px; background:linear-gradient(90deg,transparent,var(--aqua)); }
.on-dark .eyebrow{ color:rgba(255,255,255,.48); }

/* ---------- scroll progress: the strip unrolls ---------- */
.railwrap{ position:fixed; left:max(14px,2.2vw); top:0; bottom:0; width:2px; z-index:40; pointer-events:none; }
.railwrap::before{ content:""; position:absolute; inset:0; background:currentColor; opacity:.10; }
.railwrap{ color:var(--ink); }
.rail{
  position:absolute; left:0; top:0; width:2px; height:100%;
  transform-origin:0 0; transform:scaleY(var(--sp,0));
  background:linear-gradient(180deg,var(--aqua-b),var(--aqua) 55%,rgba(13,168,144,.25));
  box-shadow:0 0 12px rgba(63,217,192,.55);
}
@media (max-width:820px){ .railwrap{display:none;} }

/* ---------- nav ---------- */
.nav{
  position:fixed; inset:0 0 auto 0; z-index:50;
  transition:background .45s var(--ease-soft), border-color .45s var(--ease-soft), backdrop-filter .45s;
  border-bottom:1px solid transparent;
}
.nav.stuck{
  background:rgba(246,247,246,.72);
  backdrop-filter:saturate(160%) blur(14px);
  -webkit-backdrop-filter:saturate(160%) blur(14px);
  border-bottom-color:var(--line);
}
.nav-in{ display:flex; align-items:center; justify-content:space-between; height:74px; }
.brand{ display:inline-flex; align-items:center; gap:11px; font-weight:600; letter-spacing:-.02em; font-size:17px; }
.brandmark{ width:26px; height:26px; flex:none; }
.navlinks{ display:flex; align-items:center; gap:34px; }
.navlinks a{ color:var(--slate); font-size:14px; font-weight:500; letter-spacing:-.01em; transition:color .25s; }
.navlinks a:hover{ color:var(--ink); }
@media (max-width:760px){ .navlinks a:not(.btn){ display:none; } .navlinks{gap:0;} }

/* ---------- buttons ---------- */
.btn{
  display:inline-flex; align-items:center; gap:10px;
  padding:13px 22px; border-radius:999px;
  font-size:14px; font-weight:600; letter-spacing:-.01em;
  border:1px solid transparent; cursor:pointer;
  transition:transform .3s var(--ease), box-shadow .3s var(--ease), background .3s, color .3s, border-color .3s;
}
.btn-primary{ background:var(--ink); color:#fff; box-shadow:0 1px 2px rgba(10,22,32,.18),0 10px 30px -14px rgba(10,22,32,.55); }
.btn-primary:hover{ transform:translateY(-2px); box-shadow:0 2px 4px rgba(10,22,32,.2),0 20px 40px -18px rgba(10,22,32,.6); }
.btn-ghost{ border-color:var(--line); color:var(--ink); background:rgba(255,255,255,.5); }
.btn-ghost:hover{ border-color:var(--ink); transform:translateY(-2px); }
.on-dark .btn-primary{ background:var(--aqua-b); color:#04231F; box-shadow:0 0 0 1px rgba(127,244,224,.3),0 16px 44px -18px rgba(63,217,192,.75); }
.on-dark .btn-ghost{ border-color:rgba(255,255,255,.22); color:#fff; background:rgba(255,255,255,.04); }
.on-dark .btn-ghost:hover{ border-color:rgba(255,255,255,.5); }
.btn .arw{ transition:transform .35s var(--ease); }
.btn:hover .arw{ transform:translateX(4px); }

:where(a,button,input):focus-visible{
  outline:2px solid var(--aqua); outline-offset:3px; border-radius:6px;
}

/* ---------- reveal ---------- */
html.js .rv{ opacity:0; transform:translateY(22px); }
html.js .rv.in{ opacity:1; transform:none; transition:opacity .9s var(--ease), transform .9s var(--ease); }

/* ============================================================
   HERO
   ============================================================ */
.hero{ position:relative; padding:132px 0 0; overflow:hidden; }
.hero::after{ /* horizon wash */
  content:""; position:absolute; left:50%; top:44%; width:150vw; height:120vh;
  transform:translateX(-50%);
  background:radial-gradient(58% 46% at 50% 40%, rgba(63,217,192,.20), rgba(63,217,192,.06) 42%, transparent 70%);
  pointer-events:none; z-index:0;
}
.hero-grid{
  position:absolute; inset:0; z-index:0; pointer-events:none;
  background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);
  background-size:74px 74px;
  mask-image:radial-gradient(70% 55% at 50% 45%,#000 20%,transparent 78%);
  -webkit-mask-image:radial-gradient(70% 55% at 50% 45%,#000 20%,transparent 78%);
  opacity:.55;
}
h1.hero-h{
  font-size:clamp(52px,9.2vw,124px);
  margin:26px 0 0;
  max-width:16ch;
}
h1.hero-h em{ color:var(--aqua); font-style:italic; }
.hero-sub{ max-width:56ch; margin-top:26px; }
.hero-cta{ display:flex; flex-wrap:wrap; gap:12px; margin-top:34px; }
.hero-tags{ display:flex; flex-wrap:wrap; gap:10px 26px; margin-top:44px; color:var(--slate-2); }
.hero-tags span{ display:inline-flex; align-items:center; gap:9px; }
.hero-tags i{ width:5px; height:5px; border-radius:50%; background:var(--aqua); display:inline-block; box-shadow:0 0 8px var(--aqua-b); }

/* --- hero film ---------------------------------------------------------
   An oral dissolvable strip is a thin, flexible, translucent film — so it is
   drawn in SVG rather than as a box: a gently curved sheet in perspective,
   a hairline edge instead of a slab, and enough transparency that the grid
   behind it shows through. ------------------------------------------------ */
.stage{ position:relative; margin-top:22px; }
.filmsvg{ display:block; width:100%; max-width:940px; margin-inline:auto; overflow:visible; }

.film-float{ animation:filmFloat 10s var(--ease-soft) infinite; transform-origin:50% 62%; }
@keyframes filmFloat{
  0%,100%{ transform:translateY(0) rotate(0deg); }
  50%    { transform:translateY(-11px) rotate(-.45deg); }
}

/* light travelling across the sheet */
.film-sheen{ animation:filmSheen 7.5s linear infinite; }
@keyframes filmSheen{ 0%{ transform:translateX(-620px) } 100%{ transform:translateX(620px) } }

/* payload lifting off the film as it dissolves */
.film-mote{ opacity:0; animation:filmMote 5.4s var(--ease-soft) infinite; }
@keyframes filmMote{
  0%   { transform:translateY(6px)   scale(.5); opacity:0 }
  20%  { opacity:.9 }
  100% { transform:translateY(-118px) scale(.2); opacity:0 }
}

.hero-caption{ text-align:center; margin-top:8px; color:var(--slate-2); }

/* ============================================================
   SECTION SCAFFOLD
   ============================================================ */
section{ position:relative; }
.sec{ padding:clamp(96px,13vw,168px) 0; }
.sec-head{ max-width:840px; }
.sec-head h2{
  font-family:"Instrument Serif",Georgia,serif; font-weight:400;
  font-size:clamp(36px,5.4vw,66px); line-height:1.02; letter-spacing:-.02em;
  margin:20px 0 0;
}
.sec-head h2 em{ font-style:italic; color:var(--aqua); }
.on-dark .sec-head h2 em{ color:var(--aqua-b); }

.rulehead{ display:flex; align-items:baseline; gap:20px; border-top:1px solid var(--line); padding-top:16px; }
.on-dark .rulehead{ border-top-color:var(--line-dark); }

/* ---------- problem ---------- */
#problem{ background:var(--paper-2); border-block:1px solid var(--line); }
.pgrid{ display:grid; grid-template-columns:repeat(3,1fr); gap:1px; margin-top:74px; background:var(--line); border:1px solid var(--line); border-radius:20px; overflow:hidden; }
@media (max-width:860px){ .pgrid{ grid-template-columns:1fr; } }
.pcard{ background:var(--paper); padding:38px 32px 42px; transition:background .4s var(--ease-soft); }
.pcard:hover{ background:#fff; }
.pcard h3{ font-family:"Instrument Serif",Georgia,serif; font-weight:400; font-size:29px; letter-spacing:-.015em; margin:22px 0 12px; }
.pcard p{ color:var(--slate); font-size:15.5px; margin:0; }
.gl{ width:44px; height:44px; }
.pnote{ margin-top:44px; max-width:60ch; color:var(--slate); font-size:clamp(17px,1.5vw,21px); line-height:1.6; }
.pnote strong{ color:var(--ink); font-weight:600; }

/* ============================================================
   SCROLL SCENE (the centerpiece)
   ============================================================ */
.on-dark{ background:var(--ink); color:#fff; }
.on-dark .lede{ color:rgba(255,255,255,.62); }

#approach{ position:relative; overflow:clip; }
#approach::before{
  content:""; position:absolute; left:50%; top:0; width:160vw; height:100%;
  transform:translateX(-50%);
  background:
    radial-gradient(46% 32% at 50% 30%, rgba(63,217,192,.16), transparent 68%),
    radial-gradient(60% 40% at 50% 88%, rgba(13,168,144,.12), transparent 70%);
  pointer-events:none;
}
.track{ position:relative; height:400vh; }
@media (max-width:760px){ .track{ height:340vh; } }
.sticky{
  position:sticky; top:0; height:100vh; min-height:560px;
  display:flex; flex-direction:column; justify-content:center;
}
.scene{ width:100%; }
.scene svg{ width:100%; height:auto; }
/* bloodstream current */
#flow path{ animation:current 3.4s linear infinite; }
#flow path:nth-child(2){ animation-duration:2.6s; animation-direction:reverse; }
#flow path:nth-child(3){ animation-duration:4.4s; }
@keyframes current{ to{ stroke-dashoffset:-184; } }

.steps{
  display:grid; grid-template-columns:repeat(4,1fr); gap:22px;
  list-style:none; margin:clamp(20px,3.2vh,42px) 0 0; padding:20px 0 0;
  border-top:1px solid var(--line-dark);
}
@media (max-width:760px){ .steps{ grid-template-columns:repeat(2,1fr); gap:16px 18px; } }
.step{ opacity:.30; transition:opacity .5s var(--ease-soft); }
.step.on{ opacity:1; }
.step .n{ color:var(--aqua-b); }
.step h4{ font-size:16px; font-weight:600; letter-spacing:-.015em; margin:9px 0 6px; }
.step p{ font-size:13.5px; line-height:1.55; color:rgba(255,255,255,.55); margin:0; }
@media (max-width:760px){ .step p{ display:none; } }
.step .bar{ height:2px; background:rgba(255,255,255,.12); margin-top:12px; overflow:hidden; border-radius:2px; }
.step .bar i{ display:block; height:100%; width:100%; background:var(--aqua-b); transform-origin:0 50%; transform:scaleX(0); transition:transform .18s linear; }

.scene-cap{ margin-top:14px; color:rgba(255,255,255,.34); }

/* ---------- advantages ---------- */
.agrid{ display:grid; grid-template-columns:repeat(3,1fr); gap:26px; margin-top:72px; }
@media (max-width:980px){ .agrid{ grid-template-columns:repeat(2,1fr); } }
@media (max-width:620px){ .agrid{ grid-template-columns:1fr; } }
.acard{
  position:relative; padding:34px 30px 36px; border-radius:20px;
  background:linear-gradient(180deg,#fff,rgba(255,255,255,.55));
  border:1px solid var(--line);
  transition:transform .45s var(--ease), box-shadow .45s var(--ease), border-color .45s;
}
.acard:hover{ transform:translateY(-5px); border-color:rgba(13,168,144,.45); box-shadow:0 28px 60px -34px rgba(10,22,32,.42); }
.acard .num{ color:var(--slate-2); }
.acard h3{ font-size:20px; font-weight:600; letter-spacing:-.02em; margin:16px 0 10px; }
.acard p{ color:var(--slate); font-size:15px; margin:0; }
.acard::after{
  content:""; position:absolute; left:30px; right:30px; top:0; height:1px;
  background:linear-gradient(90deg,var(--aqua),transparent);
  opacity:0; transition:opacity .45s;
}
.acard:hover::after{ opacity:1; }

/* platform band */
.platform{ margin-top:80px; border-top:1px solid var(--line); padding-top:44px; display:grid; grid-template-columns:.9fr 1.1fr; gap:40px; }
@media (max-width:820px){ .platform{ grid-template-columns:1fr; gap:22px; } }
.plist{ list-style:none; margin:0; padding:0; }
.plist li{ display:grid; grid-template-columns:minmax(140px,180px) 1fr; gap:24px; padding:18px 0; border-bottom:1px solid var(--line); align-items:baseline; }
@media (max-width:540px){ .plist li{ grid-template-columns:1fr; gap:6px; } }
.plist li:last-child{ border-bottom:0; }
.plist .k{ font-family:"Instrument Serif",Georgia,serif; font-size:22px; letter-spacing:-.01em; }
.plist .v{ color:var(--slate); font-size:15px; }

/* ---------- CTA ---------- */
#contact{ position:relative; overflow:hidden; }
#contact::before{
  content:""; position:absolute; inset:0;
  background:radial-gradient(50% 60% at 50% 108%, rgba(63,217,192,.26), transparent 62%);
}
.ctawrap{ max-width:720px; margin-inline:auto; text-align:center; }
.ctawrap h2{ font-family:"Instrument Serif",Georgia,serif; font-weight:400; font-size:clamp(38px,6vw,72px); line-height:1.02; letter-spacing:-.022em; margin:20px 0 0; }
.ctawrap h2 em{ font-style:italic; color:var(--aqua-b); }
.ctarow{ margin:38px 0 0; }

/* ---------- footer ---------- */
footer{ background:var(--ink); color:rgba(255,255,255,.5); border-top:1px solid var(--line-dark); padding:52px 0 60px; font-size:13.5px; }
.foot-in{ display:flex; flex-wrap:wrap; gap:24px; justify-content:space-between; align-items:flex-start; }
.disclaimer{ max-width:62ch; margin-top:26px; color:rgba(255,255,255,.34); font-size:12.5px; line-height:1.65; }

.skip{ position:absolute; left:-9999px; }
.skip:focus{ left:24px; top:14px; z-index:99; background:#fff; color:var(--ink); padding:10px 16px; border-radius:8px; }

/* ---------- motion preferences ---------- */
@media (prefers-reduced-motion: reduce){
  html{ scroll-behavior:auto; }
  *,*::before,*::after{ animation-duration:.001ms !important; animation-iteration-count:1 !important; transition-duration:.001ms !important; }
  html.js .rv{ opacity:1; transform:none; }
  .track{ height:auto; }
  .sticky{ position:static; height:auto; min-height:0; padding:40px 0; }
  .step{ opacity:1; }
}