/* ============================================================
   Tersoo Samuel Awai — academic portfolio
   Quiet, classic, typography-led. Charcoal on warm paper,
   restrained oxblood accent. Newsreader + IBM Plex Sans.
   ============================================================ */

:root{
  --paper:#EEF4FB;
  --paper-2:#DEE9F5;
  --card:#F8FBFE;
  --ink:#1B1B1D;
  --ink-2:#525963;
  --ink-3:#848C97;
  --accent:#1F5FAE;
  --accent-deep:#164A87;
  --line:rgba(22,40,70,0.14);
  --line-soft:rgba(22,40,70,0.07);
  --serif:'Newsreader',Georgia,'Times New Roman',serif;
  --sans:'IBM Plex Sans',-apple-system,BlinkMacSystemFont,sans-serif;
}

*,*::before,*::after{margin:0;padding:0;box-sizing:border-box;}
html{-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;}
body{font-family:var(--sans);background:var(--paper);color:var(--ink);line-height:1.62;font-size:17px;}
a{color:inherit;text-decoration:none;}
img,video{display:block;max-width:100%;}

.wrap{max-width:1080px;margin:0 auto;padding:0 40px;}
.measure{max-width:720px;}

/* fade-in */
.fade{opacity:0;transform:translateY(14px);animation:fade .7s ease forwards;}
.fade-2{animation-delay:.08s;}
.fade-3{animation-delay:.16s;}
@keyframes fade{to{opacity:1;transform:none;}}

/* ---------- utilities ---------- */
.eyebrow{font-family:var(--sans);font-size:12px;font-weight:600;letter-spacing:0.18em;text-transform:uppercase;color:var(--accent);}
.serif{font-family:var(--serif);}
.lede{font-size:20px;line-height:1.6;color:var(--ink-2);font-weight:400;}

/* ---------- nav ---------- */
.nav{position:sticky;top:0;z-index:50;background:rgba(238,244,251,0.86);backdrop-filter:blur(16px);-webkit-backdrop-filter:blur(16px);border-bottom:1px solid var(--line-soft);}
.nav-inner{max-width:1080px;margin:0 auto;padding:0 40px;height:66px;display:flex;align-items:center;justify-content:space-between;}
.nav-name{font-family:var(--serif);font-size:20px;font-weight:500;letter-spacing:-0.01em;color:var(--ink);}
.nav-name em{font-style:italic;color:var(--accent);}
.nav-links{display:flex;align-items:center;gap:28px;}
.nav-links a{font-size:14px;font-weight:500;color:var(--ink-2);transition:color .18s;position:relative;}
.nav-links a:hover{color:var(--ink);}
.nav-links a.active{color:var(--ink);}
.nav-links a.active::after{content:"";position:absolute;left:0;right:0;bottom:-6px;height:2px;background:var(--accent);border-radius:2px;}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:6px;}
.nav-toggle span{width:22px;height:2px;background:var(--ink);border-radius:2px;transition:.3s;}
.nav-toggle.active span:nth-child(1){transform:translateY(7px) rotate(45deg);}
.nav-toggle.active span:nth-child(2){opacity:0;}
.nav-toggle.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg);}
.mobile-menu{display:none;flex-direction:column;gap:2px;padding:8px 40px 20px;border-bottom:1px solid var(--line-soft);background:var(--paper);}
.mobile-menu.open{display:flex;}
.mobile-menu a{padding:10px 0;font-size:16px;color:var(--ink-2);border-bottom:1px solid var(--line-soft);}
.mobile-menu a:last-child{border-bottom:none;}

/* ---------- page header ---------- */
.page-head{padding:76px 0 20px;}
.page-title{font-family:var(--serif);font-weight:500;font-size:clamp(38px,5vw,54px);line-height:1.05;letter-spacing:-0.02em;color:var(--ink);margin-top:14px;}
.page-rule{width:44px;height:3px;background:var(--accent);margin-top:22px;border-radius:2px;}
.page-intro{margin-top:26px;}

/* ---------- footer ---------- */
.footer{border-top:1px solid var(--line);margin-top:96px;padding:40px 0 48px;}
.footer-inner{display:flex;justify-content:space-between;align-items:flex-start;gap:28px;flex-wrap:wrap;}
.footer-name{font-family:var(--serif);font-size:18px;color:var(--ink);margin-bottom:6px;}
.footer-tag{font-size:14px;color:var(--ink-3);max-width:420px;line-height:1.5;}
.footer-links{display:flex;flex-direction:column;gap:7px;text-align:right;}
.footer-links a{font-size:14px;color:var(--ink-2);transition:color .18s;}
.footer-links a:hover{color:var(--accent);}
.footer-copy{font-size:13px;color:var(--ink-3);margin-top:10px;}

/* ---------- links inline ---------- */
.link{color:var(--accent);border-bottom:1px solid rgba(31,95,174,0.35);transition:border-color .18s;}
.link:hover{border-color:var(--accent);}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;gap:8px;font-family:var(--sans);font-size:14px;font-weight:600;padding:12px 22px;border-radius:3px;border:1px solid transparent;transition:all .2s;cursor:pointer;}
.btn-solid{background:var(--ink);color:var(--paper);}
.btn-solid:hover{background:var(--accent);}
.btn-ghost{background:transparent;color:var(--ink);border-color:var(--line);}
.btn-ghost:hover{border-color:var(--ink);}

/* ============================================================
   HOME
   ============================================================ */
.home{padding:80px 0 20px;}
.home-grid{display:grid;grid-template-columns:1fr 340px;gap:64px;align-items:start;}
.home-eyebrow{margin-bottom:20px;}
.home-name{font-family:var(--serif);font-weight:500;font-size:clamp(46px,6.5vw,76px);line-height:1.0;letter-spacing:-0.03em;color:var(--ink);}
.home-name em{font-style:italic;color:var(--accent);}
.home-role{font-family:var(--serif);font-style:italic;font-size:clamp(20px,2.4vw,26px);color:var(--ink-2);margin-top:16px;font-weight:400;}
.home-summary{margin-top:30px;max-width:560px;font-size:18px;line-height:1.7;color:var(--ink-2);}
.home-actions{margin-top:34px;display:flex;gap:12px;flex-wrap:wrap;}
.home-links{margin-top:30px;display:flex;gap:22px;flex-wrap:wrap;}
.home-links a{font-size:14px;font-weight:500;color:var(--ink-2);transition:color .18s;}
.home-links a:hover{color:var(--accent);}
.home-photo{position:relative;}
.home-photo img{display:block;width:100%;aspect-ratio:4/5;object-fit:cover;object-position:center top;border-radius:5px;filter:grayscale(10%);border:1px solid var(--line);}

/* home quick-nav cards */
.home-explore{margin-top:96px;}
.explore-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);border:1px solid var(--line);margin-top:24px;}
.explore-card{background:var(--paper);padding:28px 26px;transition:background .2s;}
.explore-card:hover{background:var(--card);}
.explore-card h3{font-family:var(--serif);font-size:21px;font-weight:500;margin-bottom:6px;}
.explore-card p{font-size:14px;color:var(--ink-3);line-height:1.5;}
.explore-card .arrow{color:var(--accent);margin-left:4px;}

/* ============================================================
   PROJECTS
   ============================================================ */
.project{padding:56px 0;border-top:1px solid var(--line);}
.project:first-of-type{border-top:none;}
.project-media{border-radius:5px;overflow:hidden;background:var(--paper-2);border:1px solid var(--line-soft);margin-bottom:26px;}
.project-media video,.project-media img{width:100%;display:block;}
.project-media.split{display:grid;grid-template-columns:2fr 1fr;gap:1px;background:var(--line-soft);}
.project-head{display:flex;justify-content:space-between;align-items:baseline;gap:20px;flex-wrap:wrap;margin-bottom:8px;}
.project-title{font-family:var(--serif);font-size:29px;font-weight:500;letter-spacing:-0.01em;}
.project-meta{font-size:13px;color:var(--ink-3);white-space:nowrap;}
.project-award{display:inline-block;font-size:12px;font-weight:600;letter-spacing:0.04em;color:var(--accent);border:1px solid rgba(31,95,174,0.3);padding:3px 10px;border-radius:100px;margin-bottom:14px;}
.project-body{max-width:760px;font-size:16px;line-height:1.72;color:var(--ink-2);}
.project-body p{margin-bottom:12px;}
.project-tags{margin-top:18px;display:flex;gap:8px;flex-wrap:wrap;}
.tag{font-size:12.5px;color:var(--ink-2);background:var(--paper-2);padding:5px 12px;border-radius:3px;}
.project-links{margin-top:20px;display:flex;gap:18px;flex-wrap:wrap;}
.project-links a{font-size:14px;font-weight:600;color:var(--ink);border-bottom:1px solid var(--line);padding-bottom:2px;transition:color .18s,border-color .18s;}
.project-links a:hover{color:var(--accent);border-color:var(--accent);}
.sim-note{display:inline-flex;align-items:center;gap:7px;font-size:12.5px;color:var(--ink-3);margin-bottom:14px;}
.sim-dot{width:7px;height:7px;border-radius:50%;background:var(--ink-3);}

/* ============================================================
   PUBLICATIONS
   ============================================================ */
.pub{padding:30px 0;border-top:1px solid var(--line);}
.pub:first-of-type{border-top:none;}
.pub-venue{font-size:13px;font-weight:600;letter-spacing:0.05em;text-transform:uppercase;color:var(--accent);margin-bottom:10px;}
.pub-title{font-family:var(--serif);font-size:24px;font-weight:500;line-height:1.25;margin-bottom:10px;}
.pub-authors{font-size:15px;color:var(--ink-2);margin-bottom:6px;}
.pub-authors .me{color:var(--ink);font-weight:600;}
.pub-cite{font-size:14px;color:var(--ink-3);font-style:italic;margin-bottom:14px;}
.pub-abstract{font-size:15px;line-height:1.7;color:var(--ink-2);max-width:720px;margin:12px 0 4px;}
.pub-abstract-toggle{margin-bottom:16px;max-width:720px;}
.pub-abstract-toggle summary{cursor:pointer;list-style:none;display:inline-flex;align-items:center;gap:8px;font-size:14px;font-weight:600;color:var(--ink);padding:8px 0;transition:color .18s;}
.pub-abstract-toggle summary:hover{color:var(--accent);}
.pub-abstract-toggle summary::-webkit-details-marker{display:none;}
.pub-abstract-toggle summary::before{content:"+";display:inline-flex;align-items:center;justify-content:center;width:18px;height:18px;border:1px solid var(--line);border-radius:3px;font-size:15px;line-height:1;color:var(--accent);transition:.18s;}
.pub-abstract-toggle[open] summary::before{content:"\2212";border-color:var(--accent);}
.pub-keywords{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:16px;}
.pub-keywords .kw{font-size:12.5px;color:var(--ink-2);background:var(--paper-2);padding:5px 12px;border-radius:3px;}
.pub-links{display:flex;gap:16px;flex-wrap:wrap;}
.pub-links a{font-size:14px;font-weight:600;color:var(--ink);border-bottom:1px solid var(--line);padding-bottom:2px;transition:.18s;}
.pub-links a:hover{color:var(--accent);border-color:var(--accent);}
.soon{margin-top:44px;padding:26px 28px;background:var(--card);border:1px solid var(--line-soft);border-radius:5px;}
.soon p{font-size:15px;color:var(--ink-2);}
.soon .eyebrow{margin-bottom:8px;display:block;}

/* ============================================================
   RESEARCH
   ============================================================ */
.thread{padding:44px 0;border-top:1px solid var(--line);}
.thread:first-of-type{border-top:none;}
.thread-grid{display:grid;grid-template-columns:200px 1fr;gap:40px;}
.thread-label{font-family:var(--sans);font-size:12px;font-weight:600;letter-spacing:0.14em;text-transform:uppercase;color:var(--ink-3);padding-top:6px;}
.thread-h{font-family:var(--serif);font-size:27px;font-weight:500;letter-spacing:-0.01em;margin-bottom:14px;}
.thread-body{max-width:640px;font-size:16px;line-height:1.75;color:var(--ink-2);}
.thread-body p{margin-bottom:14px;}
.thread-body p:last-child{margin-bottom:0;}

/* ============================================================
   PRESENTATIONS
   ============================================================ */
.talk{display:grid;grid-template-columns:1fr auto;gap:24px;align-items:center;padding:28px 0;border-top:1px solid var(--line);}
.talk:last-child{border-bottom:1px solid var(--line);}
.talk-title{font-family:var(--serif);font-size:22px;font-weight:500;line-height:1.25;margin-bottom:6px;}
.talk-venue{font-size:14.5px;color:var(--ink-2);}
.talk-venue .accent{color:var(--accent);font-weight:600;}
.talk-date{font-size:13px;color:var(--ink-3);margin-top:4px;}
.talk-action a{font-size:14px;font-weight:600;color:var(--ink);border:1px solid var(--line);border-radius:3px;padding:9px 16px;transition:.2s;white-space:nowrap;}
.talk-action a:hover{color:var(--accent);border-color:var(--accent);}

/* ============================================================
   ABOUT
   ============================================================ */
.about-grid{display:grid;grid-template-columns:1fr 300px;gap:56px;align-items:start;}
.about-body{font-size:17px;line-height:1.75;color:var(--ink-2);max-width:640px;}
.about-body p{margin-bottom:16px;}
.about-side{position:sticky;top:90px;}
.about-side .btn{width:100%;justify-content:center;margin-bottom:22px;}
.side-links{display:flex;flex-direction:column;gap:9px;}
.side-links a{font-size:14px;color:var(--ink-2);transition:color .18s;}
.side-links a:hover{color:var(--accent);}
.about-section{margin-top:56px;}
.about-section-h{font-family:var(--sans);font-size:12px;font-weight:600;letter-spacing:0.16em;text-transform:uppercase;color:var(--accent);margin-bottom:22px;}
.cv-row{display:grid;grid-template-columns:150px 1fr;gap:24px;padding:18px 0;border-top:1px solid var(--line);}
.cv-row:first-of-type{border-top:none;padding-top:0;}
.cv-when{font-size:13px;color:var(--ink-3);padding-top:2px;}
.cv-what h4{font-family:var(--serif);font-size:19px;font-weight:500;margin-bottom:3px;}
.cv-what .org{font-size:14.5px;color:var(--ink-2);margin-bottom:8px;}
.cv-what p{font-size:15px;color:var(--ink-2);line-height:1.6;}
.skills-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px 40px;}
.skill-group h4{font-family:var(--sans);font-size:13px;font-weight:600;color:var(--ink);margin-bottom:7px;}
.skill-group p{font-size:14.5px;color:var(--ink-2);line-height:1.6;}
.honor-row{padding:14px 0;border-top:1px solid var(--line);}
.honor-row:first-of-type{border-top:none;}
.honor-row h4{font-family:var(--serif);font-size:18px;font-weight:500;}
.honor-row p{font-size:14px;color:var(--ink-3);margin-top:2px;}

/* ---------- responsive ---------- */
@media(max-width:860px){
  .nav-links{display:none;}
  .nav-toggle{display:flex;}
  .wrap{padding:0 26px;}
  .nav-inner{padding:0 26px;}
  .mobile-menu{padding-left:26px;padding-right:26px;}
  .home-grid{grid-template-columns:1fr;gap:44px;}
  .home-photo{max-width:320px;}
  .home-photo::after{display:none;}
  .explore-grid{grid-template-columns:1fr;}
  .project-media.split{grid-template-columns:1fr;}
  .thread-grid{grid-template-columns:1fr;gap:12px;}
  .thread-label{padding-top:0;}
  .about-grid{grid-template-columns:1fr;gap:36px;}
  .about-side{position:static;}
  .talk{grid-template-columns:1fr;gap:14px;}
  .cv-row{grid-template-columns:1fr;gap:6px;}
  .skills-grid{grid-template-columns:1fr;}
  .footer-inner{flex-direction:column;}
  .footer-links{text-align:left;}
}
@media(max-width:460px){
  body{font-size:16px;}
  .home-actions{flex-direction:column;}
  .home-actions .btn{width:100%;justify-content:center;}
}

@media(prefers-reduced-motion:reduce){
  .fade{animation:none;opacity:1;transform:none;}
  *{scroll-behavior:auto;}
}