/* openstance.io — monochrome developer spec-sheet */

:root{
  --bg:#ffffff;
  --ink:#0a0a0a;
  --mid:#5c5c5c;
  --faint:#8f8f8f;
  --line:#e6e6e6;
  --line-strong:#111;

  --sans:"Pretendard Variable",Pretendard,-apple-system,BlinkMacSystemFont,
    "Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,monospace;

  --wrap:min(1240px,92vw);
  --gutter:clamp(1.25rem,4vw,3rem);
  --sect:clamp(4.5rem,11vh,8.5rem);
}

*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

body{
  font-family:var(--sans);
  background:var(--bg);
  color:var(--ink);
  line-height:1.6;font-weight:400;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
  overflow-x:hidden;
}
img,svg{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
h1,h2,h3{font-weight:700;letter-spacing:-.02em;word-break:keep-all;line-height:1.08}
::selection{background:var(--ink);color:var(--bg)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}

.skip{position:absolute;left:-999px;top:0;background:var(--ink);color:var(--bg);padding:.6rem 1rem;z-index:100}
.skip:focus{left:.5rem;top:.5rem}
a:focus-visible,button:focus-visible{outline:2px solid var(--ink);outline-offset:3px}

/* mono elements */
.eyebrow,.nav a,.idx,.idx-label,.hero-meta dt,.hero-meta dd,.w-year,.w-role,.w-stack,.w-tag,
.stack-cat,.chips li,.p-year,.p-meta,.c-label,.keywords li,.colophon dt,.copy,.foot-back,.count{
  font-family:var(--mono);font-feature-settings:"ss01","zero";
}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  display:flex;align-items:center;justify-content:space-between;gap:1rem;
  padding:1rem var(--gutter);
  background:color-mix(in srgb,var(--bg) 86%,transparent);
  backdrop-filter:saturate(120%) blur(9px);
  border-bottom:1px solid var(--line);
}
.brand img{height:35px;width:auto}
.nav{display:flex;align-items:center;gap:clamp(.7rem,2vw,1.6rem)}
.nav a{font-size:.76rem;letter-spacing:.02em;color:var(--mid);transition:color .18s ease}
.nav a:hover{color:var(--ink)}
.nav-cta{
  color:var(--ink)!important;border:1px solid var(--ink);
  padding:.34rem .8rem;transition:background .18s ease,color .18s ease;
}
.nav-cta:hover{background:var(--ink);color:var(--bg)!important}

/* ---------- hero ---------- */
.hero{position:relative;width:var(--wrap);margin-inline:auto;padding:clamp(3.5rem,9vh,7rem) 0 clamp(3rem,7vh,5rem)}
.eyebrow{
  font-size:.72rem;letter-spacing:.16em;color:var(--faint);
  margin-bottom:clamp(1.4rem,4vh,2.4rem);display:flex;align-items:center;gap:.75rem;
}
.eyebrow::before{content:"";width:32px;height:1px;background:var(--ink)}
.hero-title{
  font-size:clamp(2.7rem,8.4vw,7.2rem);line-height:.98;letter-spacing:-.04em;font-weight:800;max-width:15ch;
}
.hero-title .line{display:block;overflow:hidden;padding-bottom:.02em}
.hero-title .line-i{display:inline-block;transform:translateY(112%)}
.hero-title .line-i.in{transform:none}
.hero-title .rline{transition:transform .9s cubic-bezier(.16,1,.3,1)}
.brand-line{letter-spacing:-.05em}
.cursor{
  display:inline-block;width:.4em;height:.72em;margin-left:.1em;
  background:var(--ink);vertical-align:baseline;
  animation:blink 1.05s steps(1) infinite;
}
@keyframes blink{0%,49%{opacity:1}50%,100%{opacity:0}}
@media (prefers-reduced-motion:reduce){.cursor{animation:none}}
.hero-meta{
  margin-top:clamp(2.4rem,6vh,3.8rem);display:flex;flex-wrap:wrap;gap:0;
  border-top:1px solid var(--ink);
}
.hero-meta div{
  padding:1.1rem clamp(1rem,2.4vw,2rem) 1.1rem 0;margin-right:clamp(1rem,2.4vw,2rem);
  border-right:1px solid var(--line);
}
.hero-meta div:last-child{border-right:0;margin-right:0}
.hero-meta dt{font-size:.64rem;letter-spacing:.14em;text-transform:uppercase;color:var(--faint);margin-bottom:.4rem}
.hero-meta dd{font-size:.92rem;font-weight:500;color:var(--ink)}
.hero-mark{position:absolute;top:clamp(2rem,7vh,5rem);right:-2vw;width:clamp(84px,14vw,200px);height:auto;color:var(--line);z-index:-1;pointer-events:none}

/* ---------- block layout ---------- */
.block{
  width:var(--wrap);margin-inline:auto;padding-block:var(--sect);
  border-top:1px solid var(--ink);
  display:grid;grid-template-columns:minmax(0,3fr) minmax(0,9fr);gap:clamp(1.6rem,4.5vw,4rem);
}
.block-index{position:sticky;top:4.5rem;align-self:start;display:flex;gap:.9rem;height:max-content}
.idx{font-size:.78rem;color:var(--ink);font-weight:700;letter-spacing:.04em;padding-top:.2rem}
.idx-label{font-size:.7rem;letter-spacing:.14em;text-transform:uppercase;color:var(--faint);line-height:1.75}

/* about */
.lede{font-size:clamp(1.3rem,2.3vw,1.95rem);letter-spacing:-.025em;line-height:1.3;max-width:32ch;font-weight:700;word-break:keep-all}
.keywords{list-style:none;display:flex;flex-wrap:wrap;gap:.5rem;margin-top:clamp(1.8rem,4vh,2.6rem)}
.keywords li{font-size:.76rem;color:var(--mid);border:1px solid var(--line);padding:.34rem .7rem;letter-spacing:.02em}

/* ---------- work list ---------- */
.work-snapshot{font-family:var(--mono);font-size:.74rem;color:var(--faint);letter-spacing:.03em;line-height:1.7;padding-bottom:1.3rem;border-bottom:1px solid var(--line);word-break:keep-all}
.work-list{list-style:none}
.work{
  display:grid;grid-template-columns:4.2rem minmax(0,1fr) auto;
  grid-template-areas:"year main stack";
  column-gap:clamp(1rem,2.5vw,2.2rem);align-items:baseline;
  padding:clamp(1.15rem,2.6vh,1.7rem) 0;border-bottom:1px solid var(--line);
  position:relative;transition:padding-left .3s cubic-bezier(.2,.7,.2,1),background .2s ease;
}
@media(hover:hover){.work:hover{padding-left:.9rem;background:var(--ink)}}
.work:hover .w-name,.work:hover .w-year,.work:hover .w-impact,.work:hover .w-stack{color:var(--bg)}
.work:hover .w-tag{border-color:var(--bg);color:var(--bg)}
.w-year{grid-area:year;font-family:var(--mono);font-size:.78rem;color:var(--faint);padding-top:.3rem;letter-spacing:.03em;transition:color .2s ease}
.w-main{grid-area:main}
.w-name{font-size:clamp(1.1rem,1.7vw,1.35rem);letter-spacing:-.02em;font-weight:600;transition:color .2s ease}
.w-impact{font-size:.9rem;color:var(--mid);margin-top:.4rem;line-height:1.5;max-width:54ch;transition:color .2s ease;word-break:keep-all}
.w-tag{font-family:var(--mono);font-size:.56rem;vertical-align:middle;letter-spacing:.08em;border:1px solid var(--line);padding:.1rem .34rem;margin-left:.45rem;color:var(--faint);transition:border-color .2s,color .2s}
.w-stack{grid-area:stack;font-family:var(--mono);font-size:.7rem;color:var(--faint);text-align:right;white-space:nowrap;padding-top:.35rem;letter-spacing:.02em;transition:color .2s ease}
/* highlight rows */
.work--hl{padding-block:clamp(1.5rem,3.2vh,2.2rem)}
.work--hl .w-name{font-size:clamp(1.3rem,2.2vw,1.85rem)}
.work--hl .w-impact{font-size:.98rem}
/* collapsed rest + toggle */
.work-more[hidden]{display:none}
.work-toggle{
  display:inline-flex;align-items:center;gap:.5rem;margin-top:1.4rem;
  font-family:var(--mono);font-size:.74rem;letter-spacing:.06em;color:var(--ink);
  background:none;border:1px solid var(--ink);padding:.55rem 1.05rem;cursor:pointer;
  transition:background .18s ease,color .18s ease;
}
.work-toggle:hover{background:var(--ink);color:var(--bg)}
.wt-count{color:var(--faint)}
.work-toggle:hover .wt-count{color:var(--bg)}

/* ---------- stack ---------- */
.stack-grid{border-top:1px solid var(--line)}
.stack-row{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,3fr);gap:clamp(1rem,3vw,2.5rem);align-items:baseline;padding:clamp(1.05rem,2.4vh,1.6rem) 0;border-bottom:1px solid var(--line)}
.stack-cat{font-size:.76rem;letter-spacing:.06em;color:var(--ink);font-weight:600}
.chips{list-style:none;display:flex;flex-wrap:wrap;gap:.5rem}
.chips li{font-size:.78rem;color:var(--mid);border:1px solid var(--line);padding:.28rem .72rem;transition:border-color .18s ease,color .18s ease,background .18s ease}
.chips li:hover{border-color:var(--ink);color:var(--bg);background:var(--ink)}

/* ---------- research ---------- */
.paper-list{list-style:none;border-top:1px solid var(--line)}
.paper{display:grid;grid-template-columns:4.2rem minmax(0,1fr);column-gap:clamp(1rem,2.5vw,2.2rem);padding:clamp(1.15rem,2.6vh,1.7rem) 0;border-bottom:1px solid var(--line);align-items:baseline}
.p-year{font-size:.78rem;color:var(--faint);padding-top:.2rem}
.p-title{font-size:clamp(1.02rem,1.6vw,1.3rem);letter-spacing:-.02em;font-weight:600;line-height:1.3}
.p-meta{display:block;font-size:.7rem;color:var(--mid);margin-top:.55rem;letter-spacing:.03em}

/* ---------- contact ---------- */
.block--contact{border-bottom:1px solid var(--ink)}
.contact-grid{display:grid;grid-template-columns:minmax(0,1.6fr) minmax(0,1fr);gap:clamp(2rem,5vw,4rem);align-items:start}
.contact-links{list-style:none;border-top:1px solid var(--line)}
.contact-links a{display:grid;grid-template-columns:6rem 1fr auto;align-items:center;gap:1rem;padding:1.1rem 0;border-bottom:1px solid var(--line);transition:padding-left .28s ease}
@media(hover:hover){.contact-links a:hover{padding-left:.7rem}}
.c-label{font-size:.68rem;letter-spacing:.12em;text-transform:uppercase;color:var(--faint)}
.c-val{font-size:clamp(1rem,1.6vw,1.3rem);color:var(--ink);font-weight:500}
.c-arrow{color:var(--faint);font-size:1.05rem;transition:transform .28s ease,color .28s ease}
.contact-links a:hover .c-arrow{color:var(--ink);transform:translate(3px,-3px)}
.portrait{border:1px solid var(--line);padding:.5rem;max-width:360px}
.portrait img{width:100%;height:auto}
.portrait figcaption{font-family:var(--mono);font-size:.66rem;color:var(--faint);margin-top:.55rem;letter-spacing:.03em;padding:0 .1rem .1rem}

/* ---------- footer ---------- */
.site-footer{background:var(--ink);color:var(--bg);padding:clamp(3rem,7vh,5rem) var(--gutter) 2.4rem}
.foot-top{display:flex;align-items:center;justify-content:space-between;gap:1rem;padding-bottom:clamp(2rem,5vh,3rem);border-bottom:1px solid rgba(255,255,255,.16)}
.foot-logo{height:28px;width:auto}
.foot-back{font-size:.72rem;color:var(--faint);letter-spacing:.04em;transition:color .18s ease}
.foot-back:hover{color:var(--bg)}
.colophon{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:1.5rem 2.4rem;padding:clamp(2rem,5vh,3rem) 0}
.colophon dt{font-size:.62rem;letter-spacing:.14em;text-transform:uppercase;color:var(--faint);margin-bottom:.45rem}
.colophon dd{font-size:.9rem;color:#e9e9e9;line-height:1.5}
.colophon a{border-bottom:1px solid rgba(255,255,255,.3)}
.colophon a:hover{color:#fff;border-color:#fff}
.copy{display:flex;justify-content:space-between;flex-wrap:wrap;gap:.5rem;font-size:.68rem;color:var(--faint);letter-spacing:.06em;padding-top:1.5rem;border-top:1px solid rgba(255,255,255,.16)}

/* ---------- reveal ---------- */
.reveal{opacity:0;transform:translateY(12px);transition:opacity .65s cubic-bezier(.2,.7,.2,1),transform .65s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}
.hero .reveal{transition-duration:.8s}
@media (prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none;transition:none}}

/* ---------- scroll progress ---------- */
.scroll-progress{position:fixed;top:0;left:0;right:0;height:2px;z-index:60;pointer-events:none}
.scroll-progress span{display:block;height:100%;width:0;background:var(--ink);transform-origin:left}

/* ---------- custom cursor ---------- */
.cursor-dot,.cursor-ring{position:fixed;top:0;left:0;z-index:90;pointer-events:none;border-radius:50%;opacity:0;
  transform:translate(-50%,-50%);will-change:transform,width,height}
.cursor-dot{width:6px;height:6px;background:var(--ink)}
.cursor-ring{width:34px;height:34px;border:1px solid var(--ink);transition:width .25s ease,height .25s ease,background .25s ease,opacity .3s ease}
body.cursor-on .cursor-dot,body.cursor-on .cursor-ring{opacity:1}
body.cursor-hot .cursor-ring{width:56px;height:56px;background:var(--ink);mix-blend-mode:difference}
body.cursor-hot .cursor-dot{opacity:0}
@media (hover:none),(pointer:coarse){.cursor-dot,.cursor-ring{display:none}}

/* ---------- marquee ---------- */
.marquee{background:var(--ink);color:var(--bg);overflow:hidden;white-space:nowrap;padding:1.1rem 0;position:relative;z-index:2}
.marquee-track{display:inline-flex;align-items:center;gap:0;animation:marq 34s linear infinite;will-change:transform}
.marquee-track span{font-family:var(--mono);font-size:clamp(1.1rem,2.4vw,1.9rem);font-weight:600;letter-spacing:.02em;padding:0 clamp(1rem,2.4vw,2.2rem)}
.marquee-track i{font-style:normal;opacity:.55;font-size:.8em}
@keyframes marq{from{transform:translateX(0)}to{transform:translateX(-50%)}}
.marquee:hover .marquee-track{animation-play-state:paused}
@media (prefers-reduced-motion:reduce){.marquee-track{animation:none}}

/* ---------- oversized footer wordmark ---------- */
.foot-wordmark{
  font-family:var(--sans);font-weight:800;letter-spacing:-.04em;line-height:.8;
  font-size:clamp(3.5rem,20vw,17rem);color:transparent;
  -webkit-text-stroke:1px rgba(255,255,255,.34);text-stroke:1px rgba(255,255,255,.34);
  margin-top:clamp(2rem,6vh,4rem);user-select:none;overflow:hidden;
}

/* ---------- responsive ---------- */
@media (max-width:860px){
  .block{grid-template-columns:1fr;gap:1.4rem}
  .block-index{position:static;flex-direction:row;gap:.7rem;padding-bottom:.3rem}
  .idx-label br{display:none}.idx-label{display:inline}
}
@media (max-width:680px){
  .nav a:not(.nav-cta){display:none}
  .work{grid-template-columns:3.3rem 1fr;grid-template-areas:"year main" ". stack"}
  .w-stack{text-align:left;padding-top:.55rem;white-space:normal}
  .stack-row{grid-template-columns:1fr;gap:.6rem}
  .contact-grid{grid-template-columns:1fr}
  .contact-links a{grid-template-columns:1fr auto;gap:.3rem}
  .c-label{grid-column:1/-1}
  .paper{grid-template-columns:3.3rem 1fr}
  .hero-meta{flex-wrap:wrap}
  .hero-meta div{border-right:0;border-bottom:1px solid var(--line);width:calc(50% - 0px);margin-right:0;padding-right:1rem}
}