/* Yarychkivska Lab — design tokens + components (ported from the Claude Design system) */

:root{
  /* Navy */
  --navy-900:#0c1824; --navy-800:#132231; --navy-700:#1c3244; --navy-600:#2a4458; --navy-400:#5d7a91;
  /* Paper */
  --cream-50:#fcfbf9; --cream-100:#f7f5f1; --cream-200:#eeeae4; --cream-300:#e2dcd4;
  /* Claret — accent rules, eyebrows, numerals, link underlines */
  --claret-300:#dba3b1; --claret-400:#a84a62; --claret-500:#8a2c46; --claret-600:#6c1f35;
  /* Ink */
  --ink-900:#0e1a2b; --ink-700:#2c3a4a; --ink-500:#55606c; --ink-400:#7a838d;
  --line-200:#e3dfd9; --line-300:#d3cdc5;
  /* Microscopy channel colors — bright on dark, darker on cream for legibility */
  --channel-green:#3fe06a; --channel-magenta:#e03fd6;
  --label-green:#1f9e45; --label-magenta:#c42bbb; --label-blue:#2b55d6;

  /* Semantic */
  --surface-page:var(--cream-100);
  --surface-sunken:var(--cream-200);
  --surface-inverse:var(--navy-800);
  --text-heading:var(--ink-900);
  --text-body:var(--ink-700);
  --text-muted:var(--ink-500);
  --text-caption:var(--ink-500);
  --text-on-inverse-muted:#c9d3dc;
  --accent:var(--claret-500);
  --border-subtle:var(--line-200);
  --border-on-inverse:var(--navy-600);
  --link:var(--ink-900);
  --focus-ring:var(--claret-400);

  /* Typography */
  --font-display:"Sora","IBM Plex Sans",system-ui,sans-serif;
  --font-body:"IBM Plex Sans",system-ui,sans-serif;
  --fs-display:52px; --fs-h1:40px; --fs-h2:30px; --fs-h3:20px; --fs-numeral:40px;
  --fs-body:16px; --fs-eyebrow:12px; --fs-nav:14px;
  --lh-tight:1.1; --lh-snug:1.25; --lh-body:1.55;
  --ls-display:-0.02em; --ls-heading:-0.01em; --ls-eyebrow:0.14em;

  /* Spacing */
  --container-max:1200px;
  --gutter:48px;
  --rule-accent-w:24px; --rule-accent-h:2px;
  --underline-h:2px;
  --button-border-w:1.5px;
  --ease-standard:cubic-bezier(.2,.6,.2,1);
  --dur-base:200ms;
}

@media (max-width:720px){
  :root{ --gutter:20px; --fs-display:36px; --fs-h1:30px; --fs-h2:24px; --fs-numeral:32px; }
}

/* Base */
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--surface-page);color:var(--text-body);font-family:var(--font-body);font-size:var(--fs-body);line-height:var(--lh-body);-webkit-font-smoothing:antialiased}
h1,h2,h3{font-family:var(--font-display);color:var(--text-heading);margin:0;letter-spacing:var(--ls-heading);text-wrap:balance}
p{margin:0;text-wrap:pretty}
a{color:var(--link);text-decoration:none}
a:hover{color:var(--claret-600)}
a:focus-visible,button:focus-visible{outline:2px solid var(--focus-ring);outline-offset:3px}
img,video{max-width:100%}

/* Layout */
.page{min-height:100vh;display:flex;flex-direction:column}
.page > main{flex:1}
.container{max-width:var(--container-max);margin:0 auto;padding:0 var(--gutter)}
.inverse{background:var(--surface-inverse)}
.sunken{background:var(--surface-sunken)}
.stack{display:flex;flex-direction:column}
.split{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,420px),1fr));gap:48px;align-items:center}
.split-380{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,380px),1fr));gap:48px}
.split-340{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,340px),1fr));gap:24px 48px}
.body-text{font-size:16px;line-height:var(--lh-body);color:var(--text-body)}
.caption{font-size:12px;line-height:1.5;color:var(--text-caption)}
.label{font-size:12px;font-weight:600;letter-spacing:var(--ls-eyebrow);text-transform:uppercase;color:var(--text-muted)}
.label.accent{color:var(--claret-600)}
.numeral{font-family:var(--font-display);font-weight:300;font-size:var(--fs-numeral);line-height:1;color:var(--accent)}
.h2{font-weight:600;font-size:var(--fs-h2);line-height:var(--lh-snug)}
.h3{font-weight:600;font-size:var(--fs-h3);line-height:var(--lh-snug)}

/* Header */
.site-header{position:relative;z-index:20;background:var(--surface-inverse);border-bottom:1px solid var(--border-on-inverse)}
.site-header .container{height:56px;display:flex;align-items:center;justify-content:space-between;gap:24px}
.brand{display:flex;align-items:center;gap:14px;min-width:0}
.brand-name{font-family:var(--font-display);font-weight:600;font-size:22px;color:#fff;letter-spacing:var(--ls-heading);white-space:nowrap}
.brand-rule{width:1px;height:20px;background:var(--claret-300)}
.brand-tagline{font-size:12px;color:#fff;white-space:nowrap}
.site-nav{display:flex;gap:28px;align-self:stretch}
.site-nav a{display:flex;align-items:center;font-size:var(--fs-nav);font-weight:500;color:#fff}
.site-nav a:hover{color:var(--claret-300)}
.site-nav a[aria-current="page"]{color:var(--claret-300);box-shadow:inset 0 -2px 0 var(--claret-300)}
.burger{display:none;width:44px;height:44px;margin-right:-10px;flex-direction:column;align-items:center;justify-content:center;gap:6px;background:transparent;border:0;cursor:pointer;padding:0}
.burger i{display:block;width:22px;height:2px;background:#fff;transition:transform var(--dur-base) var(--ease-standard),opacity var(--dur-base) var(--ease-standard)}
.burger[aria-expanded="true"] i{background:var(--claret-300)}
.burger[aria-expanded="true"] i:nth-child(1){transform:translateY(8px) rotate(45deg)}
.burger[aria-expanded="true"] i:nth-child(2){opacity:0}
.burger[aria-expanded="true"] i:nth-child(3){transform:translateY(-8px) rotate(-45deg)}
.mobile-nav{display:none;position:absolute;left:0;right:0;top:57px;background:var(--surface-inverse);border-bottom:1px solid var(--border-on-inverse);padding:8px var(--gutter) 28px;flex-direction:column}
.mobile-nav a{display:flex;align-items:center;justify-content:space-between;min-height:52px;font-family:var(--font-display);font-weight:600;font-size:20px;letter-spacing:var(--ls-heading);color:#fff;border-bottom:1px solid var(--border-on-inverse)}
.mobile-nav a::after{content:"\2192";font-family:var(--font-body);font-weight:400;font-size:16px;color:var(--claret-300)}
.mobile-nav a[aria-current="page"]{color:var(--claret-300)}
.mobile-nav span{margin-top:20px;font-size:12px;color:var(--text-on-inverse-muted)}

@media (max-width:1099px){ .brand-rule,.brand-tagline{display:none} }
@media (max-width:919px){
  .site-nav{display:none}
  .burger{display:flex}
  .site-header.open .mobile-nav{display:flex}
  .brand-rule,.brand-tagline{display:block}
}
@media (max-width:559px){ .brand-rule,.brand-tagline{display:none} }

/* Eyebrow + section heading */
.eyebrow{display:flex;align-items:center;gap:12px;font-size:var(--fs-eyebrow);font-weight:600;letter-spacing:var(--ls-eyebrow);text-transform:uppercase;color:var(--claret-500)}
.eyebrow::before{content:"";width:var(--rule-accent-w);height:var(--rule-accent-h);background:currentColor;display:block;flex:none}
.on-dark .eyebrow,.eyebrow.on-dark{color:var(--claret-300)}
.section-heading{display:flex;flex-direction:column;gap:14px}
.section-heading h1,.section-heading h2{font-weight:600;font-size:var(--fs-h2);line-height:var(--lh-snug)}
.section-heading.large h1,.section-heading.large h2{font-size:var(--fs-h1)}
.on-dark .section-heading h1,.on-dark .section-heading h2{color:#fff}

/* Arrow link */
.arrow-link{display:inline-flex;align-items:center;gap:8px;font-weight:500;font-size:16px;color:var(--ink-900);padding-bottom:4px;border-bottom:var(--underline-h) solid var(--claret-500);transition:gap var(--dur-base) var(--ease-standard)}
.arrow-link:hover{gap:12px;color:var(--ink-900)}
.arrow-link::after{content:"\2192";font-size:1.05em}
.arrow-link.external{font-size:14px}
.arrow-link.external::after{content:"\2197"}
.on-dark .arrow-link{color:#fff;border-bottom-color:var(--claret-300)}
.on-dark .arrow-link.accent{color:var(--claret-300)}
.links{display:flex;gap:32px;flex-wrap:wrap}

/* Button */
.button{display:inline-flex;align-items:center;gap:10px;padding:14px 32px;border:var(--button-border-w) solid var(--claret-300);background:transparent;color:var(--claret-300);font-family:var(--font-body);font-size:16px;font-weight:500;white-space:nowrap;transition:background var(--dur-base) var(--ease-standard),color var(--dur-base) var(--ease-standard)}
.button::after{content:"\2192"}
.button:hover{background:var(--claret-300);color:var(--navy-800)}

/* Page hero (inner pages) */
.page-hero{padding:56px 0}
.page-hero p.lead{font-size:18px;line-height:var(--lh-body);color:#fff}
.page-hero p.muted{font-size:16px;line-height:var(--lh-body);color:var(--text-on-inverse-muted)}

/* Home hero */
.hero{padding:48px 0 56px}
.hero h1{font-weight:600;font-size:var(--fs-display);line-height:1.05;letter-spacing:var(--ls-display);color:#fff}
.hero .lead{font-size:18px;color:#fff;max-width:560px}
.hero .muted{color:var(--text-on-inverse-muted);max-width:560px}
.hero .links{gap:40px;margin-top:8px}
.hero video{display:block;width:100%;height:auto;aspect-ratio:4/3;background:#000}

/* Figure */
.figure{margin:0;display:flex;flex-direction:column;gap:10px}
.figure-frame{background:#000;overflow:hidden}
.figure-frame img{display:block;width:100%;height:auto;object-fit:cover}
.figure figcaption{font-size:12px;line-height:1.5;color:var(--text-caption)}
.on-dark .figure figcaption{color:var(--text-on-inverse-muted);text-align:right}

/* Approach band */
.approach{padding:24px 32px 28px;display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,180px),1fr));gap:32px 24px}
.approach-item{display:flex;flex-direction:column;align-items:center;text-align:center;gap:6px}
.approach-art{width:min(100%,130px);aspect-ratio:300/320;position:relative;overflow:hidden}
.approach-art img{position:absolute;top:-2.5%;width:491.3%;max-width:none;height:auto;mix-blend-mode:screen;opacity:.9}
.approach-num{font-family:var(--font-display);font-weight:300;font-size:24px;line-height:1;color:var(--claret-300)}
.approach-title{font-family:var(--font-display);font-weight:600;font-size:var(--fs-h3);color:#fff}
.approach-text{font-size:14px;line-height:1.45;color:var(--text-on-inverse-muted);max-width:240px}

/* Research list (home) */
.research-item{display:flex;flex-wrap:wrap;align-items:center;gap:12px 32px;padding:22px 0;border-bottom:1px solid var(--border-subtle)}
.research-item:last-child{border-bottom:none}
.research-item .numeral{flex:0 0 56px}
.research-item .body{flex:1 1 300px;min-width:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,220px),1fr));align-items:center;gap:8px 32px}
.research-item p{font-size:15px;line-height:1.45;color:var(--text-muted)}

/* Research page articles */
.question{display:flex;flex-wrap:wrap;gap:12px 32px;padding:40px 0;border-top:1px solid var(--border-subtle)}
.question > .numeral{flex:0 0 80px}
.question > .content{flex:1 1 320px;min-width:0}
.question h3{font-weight:600;font-size:24px;line-height:var(--lh-snug)}
.open-q{font-size:15px;line-height:1.45;color:var(--text-heading);padding:12px 0;border-top:1px solid var(--border-subtle)}
.open-q.lg{font-size:16px}
.open-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,200px),1fr));gap:32px 24px}
.open-grid .tile{background:#000;height:220px;display:flex;align-items:center;justify-content:center;overflow:hidden}
.open-grid .tile img{display:block;height:auto;clip-path:inset(2.5%)}

/* Publications */
.pub{display:grid;grid-template-columns:64px minmax(0,1fr);column-gap:24px;padding:24px 0;border-bottom:1px solid var(--border-subtle)}
.pub .year{font-family:var(--font-display);font-weight:300;font-size:24px;line-height:1.2;color:var(--accent)}
.pub h3{font-weight:600;font-size:18px;line-height:var(--lh-snug);text-wrap:pretty}
.pub .authors{font-size:14px;line-height:1.5;color:var(--text-body)}
.pub .authors strong{font-weight:600;color:var(--text-heading)}
.pub .journal{font-size:14px;color:var(--text-muted)}
.pub .links{margin-top:6px}

/* Contact */
.position{display:flex;flex-wrap:wrap;gap:12px 32px;padding:28px 0;border-bottom:1px solid var(--border-subtle)}
.position:last-child{border-bottom:none;padding-bottom:0}
.position h3{flex:0 1 200px;font-weight:600;font-size:var(--fs-h3);line-height:var(--lh-snug)}
.position .content{flex:1 1 280px;min-width:0;display:flex;flex-direction:column;gap:12px}
.contact-aside{flex:1 1 260px;min-width:0;display:flex;flex-direction:column;gap:28px;padding-top:28px;border-top:2px solid var(--claret-500)}
.contact-aside .block{display:flex;flex-direction:column;gap:6px;padding-top:24px;border-top:1px solid var(--border-subtle)}

/* CTA band */
.cta{padding:40px 0}
.cta .container{display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:20px 40px}
.cta h2{font-weight:600;font-size:30px;color:#fff}
.cta p{flex:1 1 260px;max-width:380px;font-size:14px;line-height:1.5;color:var(--text-on-inverse-muted);padding-bottom:4px}

/* Footer */
.site-footer .container{padding-top:28px;padding-bottom:28px;display:flex;align-items:center;justify-content:space-between;gap:24px;flex-wrap:wrap}
.footer-brand{display:flex;align-items:center;gap:10px}
.footer-brand strong{font-family:var(--font-display);font-weight:600;font-size:16px;color:var(--text-heading)}
.footer-brand span{font-size:12px;color:var(--text-muted)}
.footer-brand .dot{color:var(--ink-400)}
.made-in{display:inline-flex;align-items:center;gap:6px;font-size:12px;color:var(--text-muted);white-space:nowrap}
.made-in svg{display:block;width:16px;height:11px;border-radius:1px}
.footer-nav{display:flex;gap:28px;flex-wrap:wrap}
.footer-nav a{font-size:13px;color:var(--text-body)}