/* ===== Rehan Khan — shared design system =====
   Layout concept: a blueprint grid field under every section; content sits in
   "surveyed" panels marked with corner brackets, like elements picked out on
   a scan. Dark-first, committed (CAD/BIM tools read dark by default). */
:root{
  --bg:#0A1628;
  --bg-raised:#0F2039;
  --bg-sunken:#071020;
  --grid-line: rgba(63,214,232,0.07);
  --grid-line-strong: rgba(63,214,232,0.14);
  --ink:#E8EEF4;
  --ink-dim:#90A4BC;
  --ink-faint:#5A7088;
  --line:#1C3252;
  --line-strong:#2A4668;
  --cyan:#3FD6E8;
  --cyan-soft: rgba(63,214,232,0.12);
  --cyan-ink:#06222A;
  --amber:#F2A33C;
  --amber-soft: rgba(242,163,60,0.14);
  --amber-ink:#1A1206;
  --success:#53C98B;
  --danger:#E8685F;

  --font-display: 'Big Shoulders', 'Arial Narrow', sans-serif;
  --font-body: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', 'SFMono-Regular', Consolas, monospace;

  --fs-xs: 0.75rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-md: 1.125rem;
  --fs-lg: 1.375rem;
  --fs-xl: 1.875rem;
  --fs-2xl: 2.75rem;
  --fs-3xl: 4rem;
  --fs-4xl: 5.75rem;

  --space-1: 4px; --space-2: 8px; --space-3: 12px; --space-4: 16px;
  --space-5: 24px; --space-6: 32px; --space-7: 48px; --space-8: 64px;
  --space-9: 96px; --space-10: 128px;

  --radius: 3px;
  --gutter-l: max(16px, env(safe-area-inset-left, 0px));
  --gutter-r: max(16px, env(safe-area-inset-right, 0px));

  color-scheme: dark;
}

*{box-sizing:border-box;}
html,body{margin:0;}
body{
  background:var(--bg);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block;}
a{color:var(--cyan);text-decoration:none;}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible,[tabindex]:focus-visible{
  outline:2px solid var(--cyan);outline-offset:2px;border-radius:2px;
}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:700;letter-spacing:0.01em;margin:0;text-wrap:balance;}
p{margin:0;}
ul{margin:0;padding:0;list-style:none;}
button{font-family:inherit;}
.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;}

/* ---------- blueprint grid backdrop ---------- */
.blueprint-field{
  position:relative;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size:40px 40px;
  background-position:center top;
}
.blueprint-field::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background:radial-gradient(ellipse 80% 60% at 50% 0%, rgba(63,214,232,0.08), transparent 70%);
}

/* ---------- shell / container ---------- */
.shell{
  max-width:1180px;margin:0 auto;
  padding-left:var(--gutter-l);padding-right:var(--gutter-r);
}
.skip-link{
  position:absolute;left:-999px;top:0;background:var(--amber);color:var(--amber-ink);
  padding:10px 16px;font-family:var(--font-mono);font-size:var(--fs-sm);z-index:200;
}
.skip-link:focus{left:var(--gutter-l);top:8px;}

/* ---------- eyebrow / mono tags ---------- */
.eyebrow{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:var(--fs-xs);letter-spacing:0.12em;text-transform:uppercase;
  color:var(--cyan);margin-bottom:var(--space-4);
}
.eyebrow::before{content:"\25A3";font-size:0.9em;}
.mono-tag{
  font-family:var(--font-mono);font-size:var(--fs-xs);color:var(--ink-faint);
  letter-spacing:0.02em;
}

/* ---------- header / nav ---------- */
/* backdrop-filter lives on ::after, not the header element itself, so the
   header never becomes a containing block for its position:fixed descendants
   (the mobile nav drawer) — filter/backdrop-filter on an ancestor otherwise
   traps fixed-position children inside that ancestor's box. */
.site-header{
  position:sticky;top:env(safe-area-inset-top,0px);z-index:100;
  border-bottom:1px solid var(--line);
}
.site-header::after{
  content:"";position:absolute;inset:0;z-index:-1;
  background:rgba(10,22,40,0.86);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
}
.site-header::before{
  content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);
  z-index:10;background:rgba(10,22,40,0.86);
}
.nav-row{
  display:flex;align-items:center;justify-content:space-between;
  padding-block:16px;gap:24px;
}
.brand{display:flex;align-items:center;gap:10px;color:var(--ink);font-family:var(--font-display);
  font-size:1.4rem;font-weight:700;letter-spacing:0.02em;}
.brand-mark{width:30px;height:30px;color:var(--cyan);flex:none;}
.brand-mark svg{width:100%;height:100%;}
.nav-links{display:flex;align-items:center;gap:28px;}
.nav-links a{
  font-family:var(--font-mono);font-size:var(--fs-sm);color:var(--ink-dim);
  text-transform:uppercase;letter-spacing:0.06em;padding:6px 2px;position:relative;
}
.nav-links a::after{
  content:"";position:absolute;left:0;right:100%;bottom:0;height:2px;background:var(--cyan);
  transition:right 0.25s ease;
}
.nav-links a:hover{color:var(--ink);}
.nav-links a:hover::after{right:0;}
.nav-links a[aria-current="page"]{color:var(--ink);}
.nav-links a[aria-current="page"]::after{right:0;background:var(--amber);}
.nav-actions{display:flex;align-items:center;gap:16px;}
.nav-toggle{
  display:none;background:transparent;border:1px solid var(--line-strong);color:var(--ink);
  width:44px;height:44px;border-radius:var(--radius);align-items:center;justify-content:center;cursor:pointer;
}
.nav-toggle svg{width:20px;height:20px;}
.mobile-panel{display:none;}

@media (max-width: 860px){
  .nav-links{
    position:fixed;top:72px;left:0;right:0;bottom:0;background:var(--bg-sunken);
    flex-direction:column;align-items:flex-start;gap:4px;padding:24px var(--gutter-r) 24px var(--gutter-l);
    transform:translateX(100%);transition:transform 0.3s ease;overflow-y:auto;
  }
  .nav-links.is-open{transform:translateX(0);}
  .nav-links a{font-size:var(--fs-md);padding:14px 0;width:100%;border-bottom:1px solid var(--line);}
  .nav-actions .btn{display:none;}
  .nav-links .btn{display:inline-flex;margin-top:12px;}
  .nav-toggle{display:flex;}
}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-family:var(--font-mono);font-size:var(--fs-sm);text-transform:uppercase;letter-spacing:0.06em;
  padding:13px 22px;border-radius:var(--radius);border:1px solid transparent;cursor:pointer;
  min-height:44px;transition:transform 0.15s ease, background 0.2s ease, border-color 0.2s ease;
  white-space:nowrap;
}
.btn:active{transform:scale(0.97);}
.btn-primary{background:var(--amber);color:var(--amber-ink);}
.btn-primary:hover{background:#ffb75a;}
.btn-ghost{background:transparent;color:var(--cyan);border-color:var(--line-strong);}
.btn-ghost:hover{border-color:var(--cyan);background:var(--cyan-soft);}
.btn-block{width:100%;}

/* ---------- sections ---------- */
section{padding-block:var(--space-8);}
.section-head{max-width:640px;margin-bottom:var(--space-7);}
.section-head h2{font-size:var(--fs-2xl);margin-bottom:var(--space-3);}
.section-head p{color:var(--ink-dim);font-size:var(--fs-md);}
.lede{font-size:var(--fs-md);color:var(--ink-dim);max-width:720px;}

/* ---------- cards w/ corner brackets ---------- */
.bracket-card{
  position:relative;background:var(--bg-raised);border:1px solid var(--line);
  padding:var(--space-5);border-radius:var(--radius);
}
.bracket-card::before,.bracket-card::after{
  content:"";position:absolute;width:14px;height:14px;pointer-events:none;
}
.bracket-card::before{top:-1px;left:-1px;border-top:2px solid var(--cyan);border-left:2px solid var(--cyan);}
.bracket-card::after{bottom:-1px;right:-1px;border-bottom:2px solid var(--cyan);border-right:2px solid var(--cyan);}
.bracket-card:hover::before,.bracket-card:hover::after{border-color:var(--amber);}

.icon-chip{
  width:44px;height:44px;border-radius:var(--radius);background:var(--cyan-soft);
  display:flex;align-items:center;justify-content:center;color:var(--cyan);margin-bottom:var(--space-4);flex:none;
}
.icon-chip svg{width:22px;height:22px;}

/* ---------- grids ---------- */
.grid{display:grid;gap:var(--space-5);}
.grid-2{grid-template-columns:repeat(2,1fr);}
.grid-3{grid-template-columns:repeat(3,1fr);}
.grid-4{grid-template-columns:repeat(4,1fr);}
@media (max-width:980px){.grid-4{grid-template-columns:repeat(2,1fr);}.grid-3{grid-template-columns:repeat(2,1fr);}}
@media (max-width:640px){.grid-2,.grid-3,.grid-4{grid-template-columns:1fr;}}

/* ---------- stat strip ---------- */
.stat-strip{
  display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--line);
  border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;
}
.stat-tile{background:var(--bg-raised);padding:var(--space-5);min-width:0;}
.stat-num{font-family:var(--font-display);font-size:var(--fs-2xl);color:var(--cyan);font-variant-numeric:tabular-nums;line-height:1.25;}
.stat-label{font-family:var(--font-mono);font-size:var(--fs-xs);color:var(--ink-faint);text-transform:uppercase;letter-spacing:0.06em;margin-top:6px;}
@media (max-width:640px){.stat-strip{grid-template-columns:repeat(2,1fr);}}

/* ---------- process steps ---------- */
.process{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--space-5);counter-reset:step;}
.process-step{position:relative;padding-top:var(--space-6);border-top:2px solid var(--line-strong);}
.process-step::before{
  counter-increment:step;content:"0" counter(step);
  position:absolute;top:-14px;left:0;background:var(--bg);color:var(--cyan);
  font-family:var(--font-mono);font-size:var(--fs-sm);padding-right:10px;
}
.process-step h3{font-size:var(--fs-md);margin-bottom:8px;}
.process-step p{color:var(--ink-dim);font-size:var(--fs-sm);}
@media (max-width:860px){.process{grid-template-columns:repeat(2,1fr);}}
@media (max-width:640px){.process{grid-template-columns:1fr;}}

/* ---------- CTA band ---------- */
.cta-band{
  background:var(--bg-raised);border:1px solid var(--line-strong);border-radius:var(--radius);
  padding:var(--space-7) var(--space-6);display:flex;align-items:center;justify-content:space-between;gap:var(--space-5);
  flex-wrap:wrap;
}
.cta-band h2{font-size:var(--fs-xl);max-width:460px;}
.cta-band-actions{display:flex;gap:14px;flex-wrap:wrap;}

/* ---------- footer ---------- */
footer{border-top:1px solid var(--line);padding-block:var(--space-7) var(--space-6);margin-top:var(--space-8);}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr 1fr;gap:var(--space-6);margin-bottom:var(--space-6);}
.footer-brand p{color:var(--ink-dim);font-size:var(--fs-sm);margin-top:10px;max-width:280px;}
.footer-col h4{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.08em;color:var(--ink-faint);margin-bottom:12px;}
.footer-col a,.footer-col span{display:block;color:var(--ink-dim);font-size:var(--fs-sm);padding:4px 0;}
.footer-col a:hover{color:var(--cyan);}
.footer-bottom{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;border-top:1px solid var(--line);padding-top:var(--space-5);
  font-family:var(--font-mono);font-size:var(--fs-xs);color:var(--ink-faint);}
@media (max-width:860px){.footer-grid{grid-template-columns:1fr 1fr;}}
@media (max-width:640px){.footer-grid{grid-template-columns:1fr;}}

.copy-btn{background:transparent;border:1px solid var(--line-strong);color:var(--ink-dim);border-radius:var(--radius);
  font-family:var(--font-mono);font-size:var(--fs-xs);padding:4px 10px;cursor:pointer;margin-left:8px;min-height:28px;}
.copy-btn:hover{border-color:var(--cyan);color:var(--cyan);}
.copy-btn[data-copied="true"]{border-color:var(--success);color:var(--success);}

/* ---------- hero ---------- */
.hero{padding-block:var(--space-9) var(--space-8);}
.hero-grid{display:grid;grid-template-columns:1.1fr 0.9fr;gap:var(--space-7);align-items:center;}
.hero h1{font-size:var(--fs-4xl);line-height:0.98;}
.hero .lede{margin-block:var(--space-5) var(--space-6);}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap;}
.hero-visual{aspect-ratio:1/1;position:relative;}
@media (max-width:980px){
  .hero-grid{grid-template-columns:1fr;}
  .hero h1{font-size:var(--fs-3xl);}
  .hero-visual{max-width:320px;margin:0 auto;}
}

/* ---------- segment / service cards content ---------- */
.card h3{font-size:var(--fs-md);margin-bottom:8px;}
.card p{color:var(--ink-dim);font-size:var(--fs-sm);}
.card ul{margin-top:12px;display:flex;flex-direction:column;gap:6px;}
.card li{display:flex;gap:8px;font-size:var(--fs-sm);color:var(--ink-dim);}
.card li svg{width:14px;height:14px;color:var(--cyan);flex:none;margin-top:3px;}

/* ---------- case study ---------- */
.case-card{display:block;}
.case-meta{display:flex;gap:10px;flex-wrap:wrap;margin-bottom:14px;}
.pill{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.05em;
  padding:4px 9px;border:1px solid var(--line-strong);border-radius:20px;color:var(--ink-dim);}
.case-illustrative{color:var(--ink-faint);font-size:var(--fs-xs);font-style:normal;margin-top:16px;border-top:1px dashed var(--line-strong);padding-top:12px;}
.case-outcome{color:var(--cyan);font-family:var(--font-mono);font-size:var(--fs-sm);margin-top:10px;}

/* ---------- team ---------- */
.avatar-mark{
  width:56px;height:56px;border-radius:var(--radius);border:1px solid var(--line-strong);
  display:flex;align-items:center;justify-content:center;font-family:var(--font-display);
  font-size:1.2rem;color:var(--cyan);background:var(--bg-sunken);margin-bottom:var(--space-4);
}

/* ---------- forms ---------- */
.field{margin-bottom:var(--space-5);}
.field label{display:block;font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;
  letter-spacing:0.06em;color:var(--ink-dim);margin-bottom:8px;}
.field .req{color:var(--amber);}
.field input,.field select,.field textarea{
  width:100%;background:var(--bg-sunken);border:1px solid var(--line-strong);color:var(--ink);
  padding:12px 14px;border-radius:var(--radius);font-family:var(--font-body);font-size:var(--fs-base);
  min-height:44px;
}
.field textarea{min-height:120px;resize:vertical;}
.field input:focus,.field select:focus,.field textarea:focus{border-color:var(--cyan);outline:none;}
.field-hint{font-size:var(--fs-xs);color:var(--ink-faint);margin-top:6px;}
.form-success{
  background:var(--cyan-soft);border:1px solid var(--cyan);color:var(--ink);border-radius:var(--radius);
  padding:var(--space-5);display:flex;gap:12px;align-items:flex-start;
}
.form-success svg{width:20px;height:20px;color:var(--success);flex:none;margin-top:2px;}

/* ---------- contact detail panel ---------- */
.contact-row{display:flex;align-items:center;justify-content:space-between;padding:14px 0;border-bottom:1px solid var(--line);gap:10px;}
.contact-row:last-child{border-bottom:none;}
.contact-row .mono-tag{color:var(--ink-faint);}
.contact-value{font-family:var(--font-mono);font-size:var(--fs-sm);color:var(--ink);word-break:break-word;}

/* ---------- scan sweep / isometric motion ---------- */
.iso-cube{width:100%;height:100%;}
.scan-sweep{
  stroke:var(--cyan);stroke-width:1;opacity:0.7;
  transform-origin:center;
}

/* ---------- about page specific ---------- */
.about-hero{padding-block:var(--space-8) var(--space-7);}
.value-row{display:flex;gap:16px;padding:18px 0;border-bottom:1px solid var(--line);}
.value-row:last-child{border-bottom:none;}
.value-num{font-family:var(--font-mono);color:var(--ink-faint);font-size:var(--fs-sm);flex:none;width:36px;}

/* ---------- motion ---------- */
.reveal{opacity:1;}
.js-anim .reveal{opacity:0;transform:translateY(16px);}
@media (prefers-reduced-motion: reduce){
  .js-anim .reveal{opacity:1!important;transform:none!important;}
  *{animation-duration:0.001ms!important;transition-duration:0.001ms!important;}
}

/* ---------- page header (sub-pages) ---------- */
.page-header{padding-block:var(--space-8) var(--space-7);}
.page-header h1{font-size:var(--fs-3xl);}
.page-header .lede{margin-top:var(--space-4);}

@media (max-width:640px){
  .hero{padding-block:var(--space-7) var(--space-6);}
  section{padding-block:var(--space-7);}
  .page-header h1{font-size:var(--fs-2xl);}
  .cta-band{flex-direction:column;align-items:flex-start;}
}

/* ---------- solo profile (about) ---------- */
.profile-grid{display:grid;grid-template-columns:0.9fr 1.1fr;gap:var(--space-5);align-items:start;}
.profile-detail{display:grid;gap:var(--space-5);}
.profile-role{color:var(--cyan)!important;font-family:var(--font-mono);font-size:var(--fs-sm)!important;margin-block:4px 6px;}
@media (max-width:860px){.profile-grid{grid-template-columns:1fr;}}
.profile-stats{grid-template-columns:repeat(2,1fr)!important;margin-top:var(--space-5);}
.profile-stats .stat-num{font-size:var(--fs-xl);}
.timeline{display:grid;gap:0;border-left:2px solid var(--line-strong);margin-left:6px;}
.tl-item{display:grid;grid-template-columns:170px 1fr;gap:var(--space-5);padding:var(--space-5) 0 var(--space-5) var(--space-5);position:relative;border-bottom:1px solid var(--line);}
.tl-item:last-child{border-bottom:none;}
.tl-item::before{content:"";position:absolute;left:-7px;top:calc(var(--space-5) + 6px);width:12px;height:12px;background:var(--bg);border:2px solid var(--cyan);border-radius:2px;}
.tl-item:first-child::before{border-color:var(--amber);}
.tl-item h3{font-size:var(--fs-md);}
.tl-org{font-family:var(--font-mono);font-size:var(--fs-sm);color:var(--cyan);margin-block:2px 8px;}
.tl-item p:not(.tl-org){color:var(--ink-dim);font-size:var(--fs-sm);}
.tl-date{padding-top:4px;}
@media (max-width:640px){.tl-item{grid-template-columns:1fr;gap:6px;}}

/* ---------- certifications ---------- */
.cert-badge{display:inline-flex;align-items:center;gap:12px;margin-top:var(--space-6);padding:10px 16px 10px 10px;
  border:1px solid var(--amber);border-radius:var(--radius);background:var(--amber-soft);color:var(--ink);max-width:100%;}
.cert-badge:hover{background:rgba(242,163,60,0.22);}
.cert-badge-icon{width:40px;height:40px;flex:none;border-radius:var(--radius);background:var(--amber);color:var(--amber-ink);display:flex;align-items:center;justify-content:center;}
.cert-badge-icon svg{width:24px;height:24px;}
.cert-badge-kicker{display:block;font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.08em;color:var(--amber);}
.cert-badge-title{display:block;font-family:var(--font-display);font-size:var(--fs-md);font-weight:700;line-height:1.2;}
.cert-feature{display:grid;grid-template-columns:1.15fr 1fr;gap:var(--space-6);padding:var(--space-6);border-color:rgba(242,163,60,0.45);}
.cert-feature::before,.cert-feature::after{border-color:var(--amber)!important;width:22px;height:22px;}
.cert-secondary{display:grid;grid-template-columns:220px 1fr;gap:var(--space-6);padding:var(--space-6);margin-top:var(--space-5);align-items:center;}
.cert-thumb{position:relative;display:block;padding:0;border:1px solid var(--line-strong);border-radius:var(--radius);background:#fff;cursor:zoom-in;overflow:hidden;align-self:start;}
.cert-thumb img{width:100%;height:auto;display:block;transition:transform 0.3s ease;}
.cert-thumb:hover img{transform:scale(1.02);}
.cert-zoom{position:absolute;right:8px;bottom:8px;background:rgba(7,16,32,0.85);color:var(--ink)!important;padding:4px 8px;border-radius:2px;}
.cert-body h3{font-size:var(--fs-xl);line-height:1.1;margin-top:var(--space-3);}
.cert-secondary .cert-body h3{font-size:var(--fs-lg);}
.cert-flag{display:inline-flex;align-items:center;gap:6px;font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.07em;color:var(--amber);}
.cert-flag svg{width:16px;height:16px;}
.cert-flag-dim{color:var(--cyan);}
.cert-meta{display:grid;grid-template-columns:repeat(3,auto);justify-content:start;gap:var(--space-3) var(--space-6);margin:var(--space-4) 0 var(--space-5);}
.cert-secondary .cert-meta{grid-template-columns:auto 1fr;margin-bottom:0;}
.cert-meta dt{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.06em;color:var(--ink-faint);}
.cert-meta dd{margin:2px 0 0;font-family:var(--font-mono);font-size:var(--fs-sm);color:var(--ink);}
.cert-scope-label{display:block;margin-bottom:10px;text-transform:uppercase;letter-spacing:0.06em;}
.cert-dialog{border:1px solid var(--line-strong);background:var(--bg-sunken);padding:12px;border-radius:var(--radius);max-width:min(1100px,calc(100vw - 32px));max-height:calc(100vh - 32px);}
.cert-dialog::backdrop{background:rgba(4,10,20,0.85);}
.cert-dialog img{display:block;max-width:100%;max-height:calc(100vh - 80px);width:auto;height:auto;margin:0 auto;background:#fff;}
.cert-dialog-close{position:absolute;top:8px;right:8px;width:40px;height:40px;border-radius:var(--radius);border:1px solid var(--line-strong);background:var(--bg-raised);color:var(--ink);font-size:22px;cursor:pointer;z-index:1;}
@media (max-width:860px){
  .cert-feature,.cert-secondary{grid-template-columns:1fr;padding:var(--space-5);}
  .cert-thumb-tall{max-width:260px;}
  .cert-meta{grid-template-columns:1fr 1fr;}
}

/* ---------- mobile / Safari tuning ---------- */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;}
a,button{-webkit-tap-highlight-color:rgba(63,214,232,0.18);touch-action:manipulation;}
/* CTA inside the nav: keep button colours (nav link colour was overriding them) */
.nav-links a.btn{color:var(--amber-ink);padding:13px 22px;}
.nav-links a.btn::after{display:none;}
.nav-links a.btn:hover{color:var(--amber-ink);}
@media (min-width:861px){.nav-links .btn{display:none;}}
@media (max-width:860px){
  .nav-links{top:calc(76px + env(safe-area-inset-top,0px));padding-bottom:calc(24px + env(safe-area-inset-bottom,0px));overscroll-behavior:contain;}
  .nav-links a.btn{border-bottom:none;justify-content:center;}
}
body.menu-open{overflow:hidden;}
.copy-btn{min-height:36px;padding:6px 12px;}
/* certificate viewer: dynamic viewport units for iOS Safari's moving toolbar */
.cert-dialog{max-height:calc(100vh - 32px);max-height:calc(100dvh - 32px);padding:56px 12px 12px;}
.cert-dialog img{max-height:calc(100vh - 100px);max-height:calc(100dvh - 100px);}
.cert-dialog-close{top:8px;right:12px;}

/* ---------- contact details ---------- */
.contact-label{display:inline-flex;align-items:center;gap:10px;flex:none;}
.contact-ico{width:30px;height:30px;flex:none;border-radius:var(--radius);display:inline-flex;align-items:center;justify-content:center;background:var(--cyan-soft);color:var(--cyan);}
.contact-ico svg{width:18px;height:18px;}
.ico-wa{background:rgba(37,211,102,0.14);color:#3DDC7E;}
.ico-li{background:rgba(10,102,194,0.22);color:#5AA9F5;}
.contact-actions{display:flex;align-items:center;flex-wrap:wrap;justify-content:flex-end;gap:6px;min-width:0;}
a.contact-value{color:var(--ink);}
a.contact-value:hover{color:var(--cyan);}
.contact-chip{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.05em;padding:9px 12px;min-height:36px;display:inline-flex;align-items:center;border-radius:var(--radius);border:1px solid var(--line-strong);}
.chip-wa{color:#3DDC7E;border-color:rgba(61,220,126,0.45);}
.chip-wa:hover{background:rgba(37,211,102,0.12);}
.chip-li{color:#5AA9F5;border-color:rgba(90,169,245,0.45);}
.chip-li:hover{background:rgba(10,102,194,0.18);}
.footer-col a.footer-social{display:flex;align-items:center;gap:8px;}
.footer-social .contact-ico{width:24px;height:24px;}
.footer-social .contact-ico svg{width:15px;height:15px;}
.footer-col a[href^="mailto"]{word-break:break-all;}
@media (max-width:420px){.contact-row{flex-wrap:wrap;}.contact-actions{justify-content:flex-start;}}

[hidden]{display:none!important;}
.footer-col .contact-ico{display:inline-flex;padding:0;}
.contact-actions .copy-btn{margin-left:0;}

/* ---------- research & publications ---------- */
.research-head{display:flex;justify-content:space-between;align-items:flex-end;gap:var(--space-6);flex-wrap:wrap;margin-bottom:var(--space-6);}
.research-profiles{display:flex;flex-direction:column;gap:10px;min-width:260px;}
.profile-link{display:flex;align-items:center;gap:12px;padding:10px 14px;border:1px solid var(--line-strong);border-radius:var(--radius);background:var(--bg-raised);color:var(--ink);}
.profile-link:hover{border-color:var(--cyan);background:var(--cyan-soft);}
.profile-link > svg{width:16px;height:16px;color:var(--ink-faint);margin-left:auto;flex:none;}
.profile-badge{width:36px;height:36px;flex:none;border-radius:50%;display:flex;align-items:center;justify-content:center;font-family:var(--font-mono);font-weight:500;font-size:var(--fs-sm);background:var(--cyan-soft);color:var(--cyan);border:1px solid rgba(63,214,232,0.35);}
.profile-k{display:block;font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.07em;color:var(--ink-faint);}
.profile-v{display:block;font-family:var(--font-mono);font-size:var(--fs-sm);}
.research-stats{margin-bottom:var(--space-6);}
.pub-filters{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:var(--space-4);}
.pub-filter{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.06em;padding:8px 14px;min-height:38px;border-radius:20px;border:1px solid var(--line-strong);background:transparent;color:var(--ink-dim);cursor:pointer;}
.pub-filter:hover{border-color:var(--cyan);color:var(--ink);}
.pub-filter[aria-pressed="true"]{background:var(--cyan);border-color:var(--cyan);color:var(--cyan-ink);}
.pub-list{list-style:none;margin:0;padding:0;border-top:1px solid var(--line);}
.pub-item{display:grid;grid-template-columns:96px 1fr;gap:var(--space-5);padding:var(--space-5) 0;border-bottom:1px solid var(--line);}
.pub-year{font-family:var(--font-display);font-size:var(--fs-xl);font-weight:700;color:var(--ink-faint);line-height:1;padding-top:4px;}
.pub-item:hover .pub-year{color:var(--amber);}
.pub-tags{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-bottom:10px;}
.pub-type{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.05em;padding:4px 9px;border-radius:20px;}
.pub-type-journal{background:var(--amber-soft);color:var(--amber);border:1px solid rgba(242,163,60,0.4);}
.pub-type-conference{background:var(--cyan-soft);color:var(--cyan);border:1px solid rgba(63,214,232,0.4);}
.pub-type-report{background:rgba(144,164,188,0.12);color:var(--ink-dim);border:1px solid var(--line-strong);}
.pub-lead{font-family:var(--font-mono);font-size:var(--fs-xs);color:var(--success);text-transform:uppercase;letter-spacing:0.05em;}
.pub-lead::before{content:"\25CF ";}
.pub-main h3{font-family:var(--font-body);font-size:var(--fs-md);font-weight:600;line-height:1.4;letter-spacing:0;}
.pub-main h3 a{color:var(--ink);}
.pub-main h3 a:hover{color:var(--cyan);}
.pub-venue{color:var(--cyan);font-size:var(--fs-sm);font-style:italic;margin-top:4px;}
.pub-authors{color:var(--ink-dim);font-size:var(--fs-sm);margin-top:4px;}
.pub-authors b{color:var(--ink);font-weight:600;}
.pub-foot{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin-top:12px;}
.pub-doi{word-break:break-all;}
.pub-link{display:inline-flex;align-items:center;gap:6px;font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.06em;padding:8px 12px;min-height:36px;border:1px solid var(--line-strong);border-radius:var(--radius);}
.pub-link svg{width:14px;height:14px;}
.pub-link:hover{border-color:var(--cyan);background:var(--cyan-soft);}
@media (max-width:640px){
  .pub-item{grid-template-columns:1fr;gap:6px;}
  .pub-year{font-size:var(--fs-lg);}
  .research-profiles{min-width:0;width:100%;}
}
.pub-authors b{white-space:nowrap;}
.pub-type-thesis{background:rgba(83,201,139,0.12);color:var(--success);border:1px solid rgba(83,201,139,0.4);}

/* ---------- talks & events ---------- */
.event-feature,.event-card{display:grid;grid-template-columns:1.25fr 1fr;gap:var(--space-6);padding:var(--space-6);align-items:start;}
.event-card{grid-template-columns:1fr 1fr;margin-top:var(--space-5);}
.event-feature{border-color:rgba(242,163,60,0.45);}
.event-feature::before,.event-feature::after{border-color:var(--amber)!important;width:22px;height:22px;}
.event-media{display:grid;gap:10px;}
.event-feature .event-media{grid-template-columns:3fr 1fr;}
.event-photo{position:relative;display:block;padding:0;border:1px solid var(--line-strong);border-radius:var(--radius);overflow:hidden;cursor:zoom-in;background:var(--bg-sunken);}
.event-photo img{width:100%;height:100%;object-fit:cover;display:block;transition:transform 0.35s ease;}
.event-photo:hover img{transform:scale(1.03);}
.event-photo-main{aspect-ratio:3/2;}
.event-card .event-photo-main{aspect-ratio:16/9;}
.event-photo-sub{aspect-ratio:auto;height:100%;}
.event-photo-sub img{object-position:25% 50%;}
.event-body h3{font-size:var(--fs-lg);line-height:1.15;}
.event-meta{display:flex;flex-wrap:wrap;gap:6px 18px;margin:10px 0 var(--space-4);color:var(--ink-dim);}
.event-meta span{display:inline-flex;align-items:center;gap:6px;}
.event-meta svg{width:15px;height:15px;color:var(--cyan);}
.event-talk-label{display:block;text-transform:uppercase;letter-spacing:0.07em;margin-bottom:4px;}
.event-talk{font-size:var(--fs-md);font-weight:600;color:var(--ink);line-height:1.4;}
.event-desc{color:var(--ink-dim);font-size:var(--fs-sm);margin-top:var(--space-3);}
.event-links{display:flex;gap:10px;flex-wrap:wrap;margin-top:var(--space-5);}
.speaker-band{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.2fr);gap:var(--space-6);align-items:center;padding:var(--space-5);color:var(--ink);}
.speaker-band img{width:100%;aspect-ratio:3/2;object-fit:cover;border-radius:var(--radius);}
.speaker-band h2{font-size:var(--fs-xl);margin-bottom:8px;}
.speaker-band p{color:var(--ink-dim);font-size:var(--fs-sm);}
.speaker-band:hover .pub-link{border-color:var(--cyan);background:var(--cyan-soft);}
@media (max-width:860px){
  .event-feature,.event-card,.speaker-band{grid-template-columns:1fr;padding:var(--space-5);}
  .event-feature .event-media{grid-template-columns:1fr;}
  .event-photo-sub{display:none;}
}
.event-card{grid-template-columns:1.25fr 1fr;}
.event-media-pair{grid-template-columns:3fr 1fr;}
.event-card .event-photo-main{aspect-ratio:3/2;}
.event-card .event-photo-sub img{object-position:55% 50%;}
@media (max-width:860px){.event-card{grid-template-columns:1fr;}.event-media-pair{grid-template-columns:1fr;}}

.event-video{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:8px;text-align:center;padding:12px;
  border:1px solid rgba(232,104,95,0.45);border-radius:var(--radius);background:linear-gradient(160deg,rgba(232,104,95,0.16),var(--bg-sunken));color:var(--ink);min-height:100%;}
.event-video:hover{border-color:var(--danger);background:linear-gradient(160deg,rgba(232,104,95,0.26),var(--bg-sunken));}
.event-video-play{width:52px;height:52px;color:var(--danger);transition:transform 0.2s ease;}
.event-video-play svg{width:100%;height:100%;}
.event-video:hover .event-video-play{transform:scale(1.08);}
.event-video-label{font-family:var(--font-display);font-weight:700;font-size:var(--fs-md);line-height:1.15;}
@media (max-width:860px){.event-video{flex-direction:row;justify-content:flex-start;min-height:0;padding:12px 16px;text-align:left;}
  .event-video .mono-tag{margin-left:auto;}.event-video-play{width:40px;height:40px;}}

/* ---------- viewer navigation ---------- */
.cert-dialog{overflow:visible;}
.cert-dialog img{touch-action:pan-y;user-select:none;-webkit-user-select:none;}
.viewer-nav{position:absolute;top:50%;transform:translateY(-50%);width:44px;height:44px;border-radius:50%;
  border:1px solid var(--line-strong);background:rgba(7,16,32,0.82);color:var(--ink);cursor:pointer;display:flex;align-items:center;justify-content:center;z-index:2;}
.viewer-nav svg{width:22px;height:22px;}
.viewer-nav:hover{border-color:var(--cyan);color:var(--cyan);}
.viewer-prev{left:20px;}
.viewer-next{right:20px;}
.viewer-counter{position:absolute;top:18px;left:16px;color:var(--ink-dim);padding:4px 10px;border:1px solid var(--line-strong);border-radius:20px;background:var(--bg-raised);}
@media (max-width:640px){.viewer-prev{left:16px;}.viewer-next{right:16px;}.viewer-nav{width:40px;height:40px;}}

/* ---------- education ---------- */
.edu-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:var(--space-5);}
.edu-card{display:flex;flex-direction:column;padding:var(--space-6) var(--space-5);}
.edu-head{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-bottom:var(--space-4);}
.edu-icon{width:36px;height:36px;border-radius:var(--radius);background:var(--cyan-soft);color:var(--cyan);display:inline-flex;align-items:center;justify-content:center;flex:none;}
.edu-icon svg{width:20px;height:20px;}
.edu-card h3{font-size:var(--fs-lg);line-height:1.15;}
.edu-detail{color:var(--ink-dim);font-size:var(--fs-sm);}
.edu-status,.edu-grade{font-family:var(--font-mono);font-size:var(--fs-xs);text-transform:uppercase;letter-spacing:0.05em;padding:3px 9px;border-radius:20px;margin-left:auto;}
.edu-status{color:var(--amber);background:var(--amber-soft);border:1px solid rgba(242,163,60,0.4);}
.edu-grade{color:var(--success);background:rgba(83,201,139,0.12);border:1px solid rgba(83,201,139,0.4);}
.edu-current{border-color:rgba(242,163,60,0.45);}
.edu-current::before,.edu-current::after{border-color:var(--amber)!important;}
.edu-current .edu-icon{background:var(--amber-soft);color:var(--amber);}
.edu-link{margin-top:auto;align-self:flex-start;}
.edu-card .edu-detail{margin-bottom:var(--space-4);}
@media (max-width:980px){.edu-grid{grid-template-columns:1fr;}}
.lang-list{display:grid;grid-template-columns:1fr 1fr;gap:10px 24px;margin-top:12px;}
.lang-list div{display:flex;flex-direction:column;padding:10px 12px;border:1px solid var(--line);border-radius:var(--radius);background:var(--bg-sunken);}
.lang-list span:first-child{font-weight:600;font-size:var(--fs-sm);}

/* ---------- personal brand mark ---------- */
.brand-rk{display:inline-flex;align-items:center;justify-content:center;border:1.5px solid var(--cyan);border-radius:var(--radius);
  font-family:var(--font-mono);font-weight:500;font-size:0.82rem;letter-spacing:0.04em;color:var(--cyan);background:var(--cyan-soft);}
.brand-text{display:flex;flex-direction:column;line-height:1.05;}
.brand-name{font-family:var(--font-display);font-size:1.35rem;font-weight:700;letter-spacing:0.02em;}
.brand-sub{font-family:var(--font-mono);font-size:0.62rem;text-transform:uppercase;letter-spacing:0.12em;color:var(--ink-faint);margin-top:3px;}
@media (max-width:380px){.brand-sub{display:none;}}

.footer-legal{display:inline-flex;gap:16px;}
.footer-legal a{color:var(--ink-faint);}
.footer-legal a:hover{color:var(--cyan);}
.legal{max-width:760px;}
.legal h2{font-size:var(--fs-lg);margin:var(--space-6) 0 var(--space-3);}
.legal p,.legal li{color:var(--ink-dim);margin-bottom:var(--space-3);}
.legal ul{list-style:disc;padding-left:1.2em;}
.legal .placeholder{background:var(--amber-soft);color:var(--amber);padding:0 4px;border-radius:2px;}