/* Kristen Meng — personal site
   Black & white minimal aesthetic, echoing the portfolio PDF's
   bold type + dotted-rule language. */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=Inter:wght@400;500;600&display=swap');

:root{
  --ink:#111111;
  --paper:#ffffff;
  --muted:#6b6b6b;
  --line:#111111;
  --hair: rgba(17,17,17,0.14);
  --max: 1120px;
  --gap: 28px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  font-size:16px;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{
  font-family:'Space Grotesk',var(--inter,sans-serif);
  font-weight:600;
  letter-spacing:-0.01em;
  margin:0 0 0.5em;
}
p{margin:0 0 1em}
.wrap{max-width:var(--max);margin:0 auto;padding:0 24px}

/* ---------- header ---------- */
.site-header{
  border-bottom:1px solid var(--hair);
  position:sticky;top:0;background:rgba(255,255,255,0.92);
  backdrop-filter:blur(6px);
  z-index:50;
}
.site-header .wrap{
  display:flex;align-items:center;justify-content:space-between;
  height:72px;
}
.logo{
  font-family:'Space Grotesk',sans-serif;
  font-weight:600;font-size:19px;letter-spacing:0.01em;
}
.logo span{color:var(--muted);font-weight:400}
nav.main-nav{display:flex;align-items:center;gap:34px}
nav.main-nav a{
  font-size:14px;font-weight:500;letter-spacing:0.03em;text-transform:uppercase;
  color:var(--ink);opacity:0.62;transition:opacity .15s;
}
nav.main-nav a:hover,nav.main-nav a.active{opacity:1}
.btn-resume{
  border:1px solid var(--ink)!important;
  padding:8px 16px;border-radius:999px;
  opacity:1!important;text-transform:none!important;letter-spacing:0!important;font-size:13px!important;
}
.btn-resume:hover{background:var(--ink);color:var(--paper)}
.nav-toggle{display:none}

/* ---------- footer ---------- */
footer.site-footer{
  border-top:1px solid var(--hair);
  margin-top:96px;
  padding:36px 0;
}
footer.site-footer .wrap{
  display:flex;flex-wrap:wrap;gap:12px 28px;align-items:center;justify-content:space-between;
}
footer .foot-links{display:flex;gap:22px;flex-wrap:wrap}
footer .foot-links a{font-size:14px;opacity:0.7}
footer .foot-links a:hover{opacity:1;text-decoration:underline}
footer .copyright{font-size:13px;color:var(--muted)}

/* ---------- dotted rule, used like the portfolio cover ---------- */
.dotted-rule{
  border:none;border-top:1.5px dotted var(--ink);
  margin:0;
}

/* ---------- hero (home) ---------- */
.hero{padding:96px 0 64px;}
.hero .eyebrow{
  font-size:13px;text-transform:uppercase;letter-spacing:0.12em;color:var(--muted);
  margin-bottom:18px;
}
.hero h1{font-size:clamp(30px,4.4vw,52px);line-height:1.18;max-width:920px;font-weight:600;}
.hero .current-work{
  margin-top:28px;max-width:680px;color:var(--muted);font-size:15.5px;
  border-left:2px solid var(--ink);padding-left:16px;
}
.hero .cta-row{margin-top:40px;display:flex;gap:16px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:13px 26px;border-radius:999px;border:1px solid var(--ink);
  font-size:14px;font-weight:500;
}
.btn.solid{background:var(--ink);color:var(--paper)}
.btn.solid:hover{opacity:0.82}
.btn.ghost:hover{background:var(--ink);color:var(--paper)}

.section-label{
  font-size:13px;text-transform:uppercase;letter-spacing:0.12em;color:var(--muted);
  display:flex;align-items:center;gap:14px;margin:0 0 28px;
}
.section-label::after{content:"";flex:1;border-top:1px dotted var(--hair)}

/* ---------- featured grid on home ---------- */
.grid{
  display:grid;grid-template-columns:repeat(3,1fr);gap:var(--gap);
}
.card{display:block}
.card .thumb{
  aspect-ratio:4/3;overflow:hidden;background:#f2f2f2;
  border:1px solid var(--hair);
}
.card .thumb img{width:100%;height:100%;object-fit:cover;transition:transform .5s ease}
.card:hover .thumb img{transform:scale(1.045)}
.card .meta{padding-top:14px}
.card .tags{font-size:12px;text-transform:uppercase;letter-spacing:0.06em;color:var(--muted);margin-bottom:6px}
.card h3{font-size:19px;margin-bottom:4px}
.card .desc{font-size:14px;color:var(--muted);margin:0}

section{padding:56px 0}
.home-work{padding-top:8px}

/* ---------- work page filter ---------- */
.filter-bar{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:44px}
.filter-bar button{
  font-family:inherit;font-size:13px;letter-spacing:0.02em;
  padding:9px 18px;border-radius:999px;border:1px solid var(--hair);
  background:transparent;color:var(--ink);cursor:pointer;transition:.15s;
}
.filter-bar button:hover{border-color:var(--ink)}
.filter-bar button.active{background:var(--ink);color:var(--paper);border-color:var(--ink)}
.work-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:36px 32px}
.work-grid .card.hidden{display:none}
.work-grid .thumb{aspect-ratio:16/11}

/* ---------- about page ---------- */
.about-top{display:grid;grid-template-columns:220px 1fr;gap:56px;align-items:start;padding:72px 0 24px}
.about-photo{
  width:220px;height:220px;border-radius:50%;overflow:hidden;background:#eee;border:1px solid var(--hair);
}
.about-photo img{width:100%;height:100%;object-fit:cover}
.about-intro h1{font-size:clamp(26px,3.6vw,38px);margin-bottom:10px}
.about-intro .role{color:var(--muted);font-size:15px;margin-bottom:18px}
.about-intro p{max-width:640px}
.about-intro .link-row{display:flex;gap:14px;margin-top:20px;flex-wrap:wrap}
.pill-link{
  border:1px solid var(--ink);border-radius:999px;padding:9px 18px;font-size:13.5px;
}
.pill-link:hover{background:var(--ink);color:var(--paper)}

.two-col{display:grid;grid-template-columns:1fr 1fr;gap:48px}
.entry{margin-bottom:22px}
.entry .when{font-size:13px;color:var(--muted);letter-spacing:0.02em}
.entry h4{font-size:16.5px;margin:2px 0 4px}
.entry .sub{font-size:14px;color:var(--muted);margin-bottom:6px}
.entry ul{margin:6px 0 0;padding-left:18px;font-size:14.5px}
.entry ul li{margin-bottom:4px}

.skills-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:24px 40px}
.skill-group h4{font-size:13px;text-transform:uppercase;letter-spacing:0.08em;color:var(--muted);margin-bottom:10px;font-weight:600}
.skill-group p{font-size:14.5px;margin:0}

.pub{
  border:1px solid var(--hair);border-radius:10px;padding:24px 26px;margin-bottom:16px;
}
.pub .venue{font-size:12.5px;text-transform:uppercase;letter-spacing:0.06em;color:var(--muted);margin-bottom:8px}
.pub h4{font-size:17px;margin-bottom:8px;line-height:1.4}
.pub .authors{font-size:14px;color:var(--muted);margin-bottom:10px}
.pub .pub-links{display:flex;gap:16px;font-size:13.5px}
.pub .pub-links a{text-decoration:underline;text-underline-offset:3px}

.awards li{margin-bottom:8px;font-size:14.5px}

/* ---------- project detail page ---------- */
.proj-hero{padding:64px 0 8px}
.proj-hero .back{font-size:13px;color:var(--muted);margin-bottom:26px;display:inline-block}
.proj-hero .back:hover{color:var(--ink)}
.proj-hero .tags{font-size:12.5px;text-transform:uppercase;letter-spacing:0.06em;color:var(--muted);margin-bottom:14px}
.proj-hero h1{font-size:clamp(28px,4vw,44px)}
.proj-hero .subtitle{font-size:17px;color:var(--muted);max-width:720px;margin-top:4px}
.proj-meta{
  display:flex;gap:36px;flex-wrap:wrap;margin:28px 0 8px;padding:20px 0;
  border-top:1px dotted var(--hair);border-bottom:1px dotted var(--hair);
  font-size:13.5px;
}
.proj-meta div span{display:block;color:var(--muted);font-size:12px;text-transform:uppercase;letter-spacing:0.06em;margin-bottom:4px}
.proj-body{padding:36px 0 8px;max-width:760px}
.proj-body p{font-size:15.5px}
.proj-gallery{padding:12px 0 48px;display:flex;flex-direction:column;gap:22px}
.proj-gallery img{border:1px solid var(--hair);width:100%}
.proj-links{display:flex;gap:16px;margin-top:8px;flex-wrap:wrap}
.proj-nav{
  display:flex;justify-content:space-between;padding:32px 0 64px;border-top:1px dotted var(--hair);
  font-size:14px;
}

/* ---------- other-works sub-cards ---------- */
.subprojects{display:flex;flex-direction:column;gap:56px}
.subproject h3{font-size:20px;margin-bottom:4px}
.subproject .when{font-size:13px;color:var(--muted);margin-bottom:12px}

/* ---------- responsive ---------- */
@media (max-width:860px){
  .grid{grid-template-columns:repeat(2,1fr)}
  .work-grid{grid-template-columns:1fr}
  .about-top{grid-template-columns:1fr;gap:24px}
  .about-photo{width:150px;height:150px}
  .two-col{grid-template-columns:1fr}
  .skills-grid{grid-template-columns:1fr}
  nav.main-nav{gap:18px}
}
@media (max-width:560px){
  .grid{grid-template-columns:1fr}
  .hero{padding:64px 0 40px}
  section{padding:40px 0}
  .site-header .wrap{height:64px}
  nav.main-nav{gap:14px}
  nav.main-nav a{font-size:12.5px}
}