/* ============================================================
   Praveen T N — Portfolio Stylesheet
   Palette: black (#0a0a0a) / white (#fff) / greys
   ============================================================ */

:root {
  --ink:      #0a0a0a;
  --ink-soft: #111111;
  --ink-mid:  #1a1a1a;
  --ink-muted:#2a2a2a;
  --graphite: #4a4a4a;
  --silver:   #888888;
  --mist:     #bbbbbb;
  --cloud:    #e2e2e2;
  --fog:      #f2f2f2;
  --snow:     #fafafa;
  --white:    #ffffff;

  --font-sans: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Mono', monospace;

  --max-w: 1100px;
  --radius: 0;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-sans);
  background: var(--snow);
  color: var(--ink);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--ink); color: var(--white); }

a { color: inherit; text-decoration: none; }

/* ── Typography ─────────────────────────────────────────────── */
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.02em; font-weight: 800; }

.label {
  font-family: var(--font-mono);
  font-size: .65rem;
  font-weight: 500;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--silver);
  display: block;
  margin-bottom: .6rem;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: .65rem;
  font-weight: 500;
  letter-spacing: .08em;
  padding: .25rem .55rem;
  border: 1px solid var(--cloud);
  background: var(--fog);
  color: var(--graphite);
}

/* ── Layout ─────────────────────────────────────────────────── */
.container { max-width: var(--max-w); margin: 0 auto; padding: 0 2rem; }
@media (max-width: 768px) { .container { padding: 0 1.25rem; } }

.section { padding: 6rem 0; }
.section--dark { background: var(--ink); color: var(--white); }
.section--fog  { background: var(--fog); }
.section--white{ background: var(--white); }

.section-head { margin-bottom: 3.5rem; }
.section-head h2 { font-size: clamp(1.8rem, 4vw, 2.6rem); color: inherit; }
.section-head h2 span { color: var(--silver); }
.section--dark .section-head h2 span { color: rgba(255,255,255,.35); }
.section--dark .label { color: rgba(255,255,255,.3); }

/* ── Buttons ─────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .78rem; font-weight: 600; letter-spacing: .06em;
  padding: .65rem 1.3rem; cursor: pointer; border: none;
  transition: background .18s, color .18s, border-color .18s;
  font-family: var(--font-sans);
}
.btn-primary { background: var(--ink); color: var(--white); }
.btn-primary:hover { background: var(--ink-mid); }
.btn-outline { background: transparent; color: var(--ink); border: 1px solid var(--ink); }
.btn-outline:hover { background: var(--ink); color: var(--white); }
.btn-ghost {
  background: transparent; color: var(--silver);
  border: none; font-size: .75rem; padding: .4rem .6rem;
}
.btn-ghost:hover { color: var(--ink); }
.btn-danger { background: transparent; color: #c0392b; border: none; font-size: .75rem; padding: .4rem .6rem; cursor: pointer; font-family: var(--font-sans); }
.btn-danger:hover { background: #c0392b; color: white; }
.btn-sm { padding: .4rem .9rem; font-size: .72rem; }

/* ── Header ──────────────────────────────────────────────────── */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: 64px;
  display: flex; align-items: center;
  transition: background .25s, box-shadow .25s, border-color .25s;
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: rgba(250,250,250,.96);
  backdrop-filter: blur(8px);
  border-bottom-color: var(--cloud);
  box-shadow: 0 1px 0 var(--cloud);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; width: 100%; }

.header-logo { display: flex; flex-direction: column; line-height: 1.25; }
.header-logo .name {
  font-weight: 800; font-size: .9rem; letter-spacing: -.01em;
  color: var(--white); transition: color .25s;
}
.header-logo .sub {
  font-size: .65rem; font-family: var(--font-mono);
  color: rgba(255,255,255,.5); transition: color .25s;
}
.site-header.scrolled .header-logo .name { color: var(--ink); }
.site-header.scrolled .header-logo .sub { color: var(--silver); }

.header-nav { display: flex; align-items: center; gap: 2rem; }
@media (max-width: 768px) { .header-nav { display: none; } }

.header-nav a {
  position: relative;
  font-size: .7rem; font-weight: 600; letter-spacing: .18em; text-transform: uppercase;
  color: rgba(255,255,255,.5); transition: color .2s;
}
.header-nav a::after {
  content: '';
  position: absolute;
  bottom: -6px; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, #fff 0%, rgba(255,255,255,0) 100%);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .25s ease;
  border-radius: 2px;
}
.header-nav a:hover,
.header-nav a.active { color: #fff; }
.header-nav a:hover::after,
.header-nav a.active::after { transform: scaleX(1); }

.site-header.scrolled .header-nav a { color: var(--graphite); }
.site-header.scrolled .header-nav a::after {
  background: linear-gradient(90deg, var(--ink) 0%, rgba(20,20,20,0) 100%);
}
.site-header.scrolled .header-nav a:hover,
.site-header.scrolled .header-nav a.active { color: var(--ink); }

.header-cta {
  font-size: .7rem; font-weight: 600; letter-spacing: .1em;
  padding: .55rem 1.1rem;
  border: 1px solid rgba(255,255,255,.4);
  color: var(--white);
  transition: all .2s;
}
.header-cta:hover { background: var(--white); color: var(--ink); border-color: var(--white); }
.site-header.scrolled .header-cta { border-color: var(--ink); color: var(--ink); }
.site-header.scrolled .header-cta:hover { background: var(--ink); color: var(--white); }

/* ── Hero ────────────────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  background: var(--ink);
  display: flex; flex-direction: column; justify-content: center;
  position: relative; overflow: hidden;
  padding: 8rem 0 6rem;
}
.hero-grid {
  position: absolute; inset: 0; opacity: .03;
  background-image:
    linear-gradient(#fff 1px, transparent 1px),
    linear-gradient(90deg, #fff 1px, transparent 1px);
  background-size: 80px 80px;
}
.hero-content { position: relative; }
.hero-pre {
  display: flex; align-items: center; gap: .75rem;
  margin-bottom: 2rem;
  opacity: 0; animation: fadeUp .6s .1s forwards;
}
.hero-pre::before { content: ''; display: block; width: 2rem; height: 1px; background: rgba(255,255,255,.3); }
.hero-pre span { font-family: var(--font-mono); font-size: .65rem; letter-spacing: .3em; text-transform: uppercase; color: rgba(255,255,255,.35); }

/* hero h1 — defined in additions below */
.hero-title-line { display: inline; }

.hero-role {
  display: flex; align-items: center; gap: 1rem;
  margin: 1.5rem 0 2rem;
  opacity: 0; animation: fadeUp .6s .3s forwards;
}
.hero-role::before { content: ''; display: block; width: 3rem; height: 1px; background: rgba(255,255,255,.2); }
.hero-role p { font-size: .9rem; font-weight: 500; color: rgba(255,255,255,.55); letter-spacing: .02em; }

.hero-tagline {
  max-width: 600px;
  font-size: clamp(.95rem, 2vw, 1.15rem);
  color: rgba(255,255,255,.38);
  line-height: 1.7; font-weight: 300;
  margin-bottom: 3rem;
  opacity: 0; animation: fadeUp .6s .4s forwards;
}

.hero-actions {
  display: flex; flex-wrap: wrap; align-items: center; gap: 1rem;
  opacity: 0; animation: fadeUp .6s .5s forwards;
}
.hero-actions .btn-primary { background: var(--white); color: var(--ink); }
.hero-actions .btn-primary:hover { background: var(--fog); }
.hero-actions .btn-outline-light {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .78rem; font-weight: 600; letter-spacing: .06em;
  padding: .65rem 1.3rem;
  border: 1px solid rgba(255,255,255,.25); color: rgba(255,255,255,.7);
  transition: all .2s;
}
.hero-actions .btn-outline-light:hover { border-color: rgba(255,255,255,.6); color: var(--white); }
.hero-email { font-family: var(--font-mono); font-size: .72rem; color: rgba(255,255,255,.3); }
.hero-email:hover { color: rgba(255,255,255,.6); }

.hero-scroll {
  position: absolute; bottom: 3rem; left: 50%; transform: translateX(-50%);
  display: flex; flex-direction: column; align-items: center; gap: .6rem;
  opacity: .3;
}
.hero-scroll span { font-family: var(--font-mono); font-size: .6rem; letter-spacing: .2em; color: var(--white); }
.hero-scroll-line { width: 1px; height: 3rem; background: linear-gradient(to bottom, white, transparent); }

.hero-gradient { position: absolute; bottom: 0; left: 0; right: 0; height: 6rem; background: linear-gradient(to top, var(--snow), transparent); }

/* ── Impact strip ────────────────────────────────────────────── */
.impact-strip { background: var(--ink); padding: 0; margin-top: -1px; }
.impact-grid { display: grid; grid-template-columns: repeat(3, 1fr); }
@media (min-width: 900px) { .impact-grid { grid-template-columns: repeat(6, 1fr); } }
.impact-cell {
  background: var(--ink-soft);
  padding: 2.25rem 1.75rem;
  border: 1px solid var(--ink-muted);
  transition: background .2s;
  cursor: default;
}
.impact-cell:hover { background: var(--ink-mid); }
.impact-metric {
  font-size: clamp(1.8rem, 4vw, 2.6rem); font-weight: 900;
  color: var(--white); letter-spacing: -.04em; line-height: 1;
  display: block;
}
.impact-label {
  font-size: .7rem; font-weight: 700; color: rgba(255,255,255,.6);
  letter-spacing: .04em; margin-top: .35rem; line-height: 1.3;
}
.impact-desc {
  font-size: .65rem; color: rgba(255,255,255,.25); margin-top: .5rem;
  line-height: 1.4; display: none;
}
.impact-cell:hover .impact-desc { display: block; }

/* ── About ───────────────────────────────────────────────────── */
.about-grid { display: grid; grid-template-columns: 1fr; gap: 4rem; }
@media (min-width: 900px) { .about-grid { grid-template-columns: 7fr 5fr; } }

.about-bio p { font-size: 1rem; color: var(--graphite); line-height: 1.8; margin-bottom: 1.25rem; }
.about-links { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 2.5rem; }

.profile-card { border: 1px solid var(--cloud); background: var(--white); padding: 2rem; }
.profile-card-header { display: flex; align-items: flex-start; justify-content: space-between; margin-bottom: 1.5rem; padding-bottom: 1.5rem; border-bottom: 1px solid var(--fog); }
.profile-card-header h3 { font-size: 1.1rem; font-weight: 800; }
.profile-card-header p { font-size: .78rem; color: var(--silver); margin-top: .15rem; }
.profile-avatar {
  width: 52px; height: 52px;
  background: var(--ink); color: var(--white);
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 1.1rem;
  flex-shrink: 0;
}
.profile-meta { display: flex; flex-direction: column; gap: .65rem; }
.profile-meta-row { display: flex; align-items: baseline; justify-content: space-between; gap: 1rem; }
.profile-meta-row .meta-key { font-family: var(--font-mono); font-size: .62rem; text-transform: uppercase; letter-spacing: .1em; color: var(--silver); flex-shrink: 0; }
.profile-meta-row .meta-val { font-size: .78rem; color: var(--graphite); text-align: right; }

.awards-list { margin-top: 1.5rem; }
.award-row { display: flex; gap: .75rem; padding: .75rem 0; border-bottom: 1px solid var(--fog); }
.award-row:last-child { border-bottom: none; }
.award-dot { width: 5px; height: 5px; border-radius: 50%; background: var(--ink); margin-top: .5rem; flex-shrink: 0; }
.award-title { font-size: .85rem; font-weight: 700; color: var(--ink); }
.award-meta { font-size: .72rem; color: var(--silver); margin-top: .1rem; }

/* ── Experience ──────────────────────────────────────────────── */
.exp-layout { display: grid; grid-template-columns: 1fr; gap: 3rem; }
@media (min-width: 900px) { .exp-layout { grid-template-columns: 4fr 8fr; } }

.exp-sidebar { position: relative; }
.exp-sidebar-inner { position: sticky; top: 5rem; }
.exp-sidebar p { font-size: .85rem; color: var(--graphite); line-height: 1.7; margin-top: 1rem; }
.exp-index { margin-top: 2rem; display: flex; flex-direction: column; gap: .5rem; }
.exp-index-item { font-family: var(--font-mono); font-size: .65rem; color: var(--mist); }

.exp-timeline { position: relative; padding-left: 1.5rem; }
.exp-timeline::before { content: ''; position: absolute; left: 0; top: 0; bottom: 0; width: 1px; background: linear-gradient(to bottom, transparent, var(--cloud) 8%, var(--cloud) 92%, transparent); }

.exp-item { position: relative; padding-bottom: 2.5rem; }
.exp-item:last-child { padding-bottom: 0; }
.exp-dot { position: absolute; left: -1.5rem; top: .4rem; width: 8px; height: 8px; border: 2px solid var(--mist); background: var(--snow); border-radius: 50%; transform: translateX(-3.5px); transition: border-color .2s, background .2s; }
.exp-item.active .exp-dot, .exp-item:hover .exp-dot { border-color: var(--ink); background: var(--ink); }

.exp-card {
  border: 1px solid transparent; padding: 1.5rem;
  cursor: pointer; transition: border-color .2s, background .2s;
}
.exp-item.open .exp-card, .exp-card:hover { border-color: var(--cloud); background: var(--white); }

.exp-meta { display: flex; align-items: center; flex-wrap: wrap; gap: .5rem; margin-bottom: .4rem; }
.exp-period { font-family: var(--font-mono); font-size: .65rem; color: var(--silver); }
.exp-badge { font-family: var(--font-mono); font-size: .6rem; background: var(--ink); color: var(--white); padding: .15rem .45rem; }

.exp-role { font-size: 1.05rem; font-weight: 800; color: var(--ink); letter-spacing: -.01em; }
.exp-company { font-size: .82rem; font-weight: 500; color: var(--silver); margin-top: .1rem; }
.exp-location { font-size: .72rem; color: var(--mist); margin-top: .05rem; }

.exp-tagline {
  font-size: .83rem; color: var(--graphite); font-style: italic; line-height: 1.6;
  border-left: 2px solid var(--fog); padding-left: .75rem; margin-top: .85rem;
}

.exp-highlights {
  margin-top: 1.25rem; padding-top: 1.25rem; border-top: 1px solid var(--fog);
  display: none;
}
.exp-item.open .exp-highlights { display: block; }
.exp-highlights ul { list-style: none; display: flex; flex-direction: column; gap: .75rem; }
.exp-highlights li { display: flex; gap: .75rem; font-size: .85rem; color: var(--graphite); line-height: 1.65; }
.exp-highlights li::before { content: '—'; color: var(--mist); flex-shrink: 0; margin-top: .05rem; }

.exp-toggle { float: right; font-size: .7rem; color: var(--mist); margin-top: .2rem; user-select: none; }
.exp-item.open .exp-toggle::after { content: 'collapse'; }
.exp-item:not(.open) .exp-toggle::after { content: 'expand'; }

/* ── Skills ──────────────────────────────────────────────────── */
.skills-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--cloud); }
@media (min-width: 768px) { .skills-grid { grid-template-columns: repeat(3, 1fr); } }

.skill-card {
  background: var(--snow); padding: 2rem;
  transition: background .2s;
}
.skill-card:hover { background: var(--white); }
.skill-num { font-family: var(--font-mono); font-size: .65rem; color: var(--mist); float: right; }
.skill-cat { font-size: .82rem; font-weight: 800; color: var(--ink); margin-bottom: 1rem; }
.skill-tags { display: flex; flex-wrap: wrap; gap: .4rem; }

/* ── Projects ────────────────────────────────────────────────── */
.projects-filter { display: flex; flex-wrap: wrap; gap: .5rem; margin-bottom: 2.5rem; }
.filter-btn {
  font-family: var(--font-mono); font-size: .65rem; font-weight: 500;
  padding: .35rem .8rem; border: 1px solid var(--cloud);
  color: var(--silver); background: transparent; cursor: pointer;
  transition: all .18s;
  letter-spacing: .06em;
}
.filter-btn:hover, .filter-btn.active { border-color: var(--ink); background: var(--ink); color: var(--white); }

.projects-grid { display: grid; grid-template-columns: 1fr; gap: 1.25rem; }
@media (min-width: 640px) { .projects-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .projects-grid { grid-template-columns: repeat(3, 1fr); } }

.project-card {
  background: var(--white); border: 1px solid var(--cloud);
  padding: 1.75rem; display: flex; flex-direction: column;
  transition: border-color .2s;
}
.project-card:hover { border-color: var(--mist); }

.project-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: .75rem; }
.project-cat { font-family: var(--font-mono); font-size: .62rem; color: var(--silver); }
.project-period { font-family: var(--font-mono); font-size: .62rem; color: var(--mist); }
.project-featured { font-family: var(--font-mono); font-size: .58rem; background: var(--ink); color: var(--white); padding: .15rem .45rem; margin-left: .4rem; }

.project-name { font-size: .95rem; font-weight: 800; color: var(--ink); letter-spacing: -.01em; margin-bottom: .25rem; }
.project-role { font-size: .72rem; color: var(--silver); margin-bottom: .85rem; }
.project-desc { font-size: .82rem; color: var(--graphite); line-height: 1.65; flex: 1; margin-bottom: 1rem; }
.project-tech { display: flex; flex-wrap: wrap; gap: .35rem; }

/* ── Education + Certs ───────────────────────────────────────── */
.edu-certs-grid { display: grid; grid-template-columns: 1fr; gap: 4rem; }
@media (min-width: 900px) { .edu-certs-grid { grid-template-columns: 1fr 1fr; } }

.edu-list { border-top: 1px solid var(--cloud); }
.edu-row { display: flex; gap: 1.5rem; padding: 1.4rem 0; border-bottom: 1px solid var(--cloud); }
.edu-year { font-family: var(--font-mono); font-size: .7rem; font-weight: 700; color: var(--ink); width: 2.8rem; flex-shrink: 0; padding-top: .15rem; text-align: right; }
.edu-degree { font-size: .9rem; font-weight: 700; color: var(--ink); line-height: 1.3; }
.edu-inst { font-size: .75rem; color: var(--silver); margin-top: .2rem; }
.edu-desc { font-size: .72rem; color: var(--mist); margin-top: .35rem; line-height: 1.5; }

.cert-list { border-top: 1px solid var(--cloud); }
.cert-row { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1rem 0; border-bottom: 1px solid var(--cloud); }
.cert-name { font-size: .85rem; font-weight: 700; color: var(--ink); line-height: 1.3; }
.cert-issuer { font-size: .72rem; color: var(--silver); margin-top: .1rem; }
.cert-year { font-family: var(--font-mono); font-size: .65rem; color: var(--mist); flex-shrink: 0; }
.cert-row.featured .cert-name { color: var(--ink); }

/* ── Research ────────────────────────────────────────────────── */
.research-grid { display: grid; grid-template-columns: 1fr; gap: 1px; background: var(--ink-muted); }
@media (min-width: 768px) { .research-grid { grid-template-columns: repeat(2, 1fr); } }

.research-card {
  background: var(--ink-soft); padding: 2.25rem;
  transition: background .2s;
}
.research-card:hover { background: var(--ink-mid); }
.research-meta { display: flex; align-items: center; gap: .75rem; margin-bottom: 1rem; }
.research-type { font-family: var(--font-mono); font-size: .6rem; border: 1px solid rgba(255,255,255,.1); color: rgba(255,255,255,.35); padding: .15rem .5rem; }
.research-area { font-family: var(--font-mono); font-size: .6rem; color: rgba(255,255,255,.2); }
.research-title { font-size: .95rem; font-weight: 700; color: var(--white); line-height: 1.4; margin-bottom: .75rem; }
.research-desc { font-size: .82rem; color: rgba(255,255,255,.4); line-height: 1.65; }

.patent-note {
  margin-top: 3rem; padding-top: 2rem; border-top: 1px solid var(--ink-muted);
  display: flex; align-items: center; gap: 1.25rem;
}
.patent-line { width: 1px; height: 3.5rem; background: rgba(255,255,255,.1); flex-shrink: 0; }
.patent-label { font-family: var(--font-mono); font-size: .6rem; text-transform: uppercase; letter-spacing: .15em; color: rgba(255,255,255,.25); margin-bottom: .35rem; }
.patent-text { font-size: .82rem; color: rgba(255,255,255,.4); }

/* ── Footer ──────────────────────────────────────────────────── */
.site-footer { background: var(--ink); color: rgba(255,255,255,.6); padding: 5rem 0 3rem; }
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 3rem; margin-bottom: 3rem; }
@media (min-width: 768px) { .footer-grid { grid-template-columns: repeat(3, 1fr); } }

.footer-brand h3 { font-size: 1.1rem; font-weight: 800; color: var(--white); margin-bottom: .25rem; }
.footer-brand p { font-size: .78rem; color: rgba(255,255,255,.35); }
.footer-col-label { font-family: var(--font-mono); font-size: .6rem; text-transform: uppercase; letter-spacing: .15em; color: rgba(255,255,255,.25); margin-bottom: 1rem; }
.footer-link { display: block; font-size: .82rem; color: rgba(255,255,255,.5); margin-bottom: .5rem; transition: color .2s; }
.footer-link:hover { color: var(--white); }
.footer-bottom { border-top: 1px solid var(--ink-muted); padding-top: 1.75rem; display: flex; flex-direction: column; gap: .5rem; }
@media (min-width: 640px) { .footer-bottom { flex-direction: row; justify-content: space-between; align-items: center; } }
.footer-bottom p { font-family: var(--font-mono); font-size: .62rem; color: rgba(255,255,255,.2); }

/* ── Scroll animations ───────────────────────────────────────── */
.reveal {
  opacity: 0; transform: translateY(20px);
  transition: opacity .55s ease, transform .55s ease;
}
.reveal.visible { opacity: 1; transform: none; }

/* ── Animations ──────────────────────────────────────────────── */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(1.5rem); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Custom scrollbar ────────────────────────────────────────── */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: var(--snow); }
::-webkit-scrollbar-thumb { background: var(--cloud); }
::-webkit-scrollbar-thumb:hover { background: var(--mist); }

/* ── Header actions (search button) ─────────────────────────── */
.header-actions { display: flex; align-items: center; gap: .75rem; }

.search-trigger {
  display: flex; align-items: center; justify-content: center;
  width: 34px; height: 34px;
  background: transparent; border: 1px solid rgba(255,255,255,.2);
  color: rgba(255,255,255,.6); cursor: pointer; transition: all .2s;
}
.search-trigger:hover { border-color: rgba(255,255,255,.5); color: var(--white); }
.site-header.scrolled .search-trigger { border-color: var(--cloud); color: var(--graphite); }
.site-header.scrolled .search-trigger:hover { border-color: var(--ink); color: var(--ink); }

/* ── Hero h1 fix (single line, appropriate size) ─────────────── */
.hero h1 {
  font-size: clamp(2rem, 4.5vw, 3.5rem);
  font-weight: 900; color: var(--white); letter-spacing: -.02em;
  line-height: 1.1;
  opacity: 0; animation: fadeUp .6s .2s forwards;
  white-space: nowrap;
}
@media (max-width: 600px) { .hero h1 { white-space: normal; font-size: clamp(1.8rem, 8vw, 2.6rem); } }

/* ── Projects: group toggle ──────────────────────────────────── */
.projects-group-toggle {
  display: flex; gap: .5rem; margin-bottom: 1rem;
  border-bottom: 1px solid var(--cloud); padding-bottom: 1rem;
}
.group-btn {
  font-family: var(--font-mono); font-size: .65rem; font-weight: 600;
  letter-spacing: .1em; text-transform: uppercase;
  padding: .4rem .9rem; border: none; cursor: pointer;
  background: transparent; color: var(--silver); transition: all .18s;
}
.group-btn.active { background: var(--ink); color: var(--white); }

/* ── Project highlights ──────────────────────────────────────── */
.project-highlights {
  margin: .75rem 0; padding: .75rem 0;
  border-top: 1px solid var(--fog); border-bottom: 1px solid var(--fog);
  display: flex; flex-direction: column; gap: .35rem;
}
.project-highlight-item {
  font-size: .75rem; color: var(--graphite); padding-left: .85rem;
  position: relative; line-height: 1.5;
}
.project-highlight-item::before { content: '—'; position: absolute; left: 0; color: var(--mist); }

/* ── Contact section ─────────────────────────────────────────── */
.contact-layout { display: grid; grid-template-columns: 1fr; gap: 5rem; }
@media (min-width: 900px) { .contact-layout { grid-template-columns: 5fr 7fr; } }

.contact-social-link {
  display: flex; align-items: center; gap: 1rem;
  padding: .9rem 1.1rem;
  border: 1px solid var(--cloud);
  font-size: .82rem; color: var(--graphite);
  transition: all .2s;
}
.contact-social-link:hover { border-color: var(--ink); color: var(--ink); background: var(--fog); }
.contact-social-icon { font-weight: 900; font-size: .8rem; width: 1.5rem; color: var(--ink); }
.contact-social-arrow { margin-left: auto; color: var(--mist); font-size: .9rem; transition: transform .2s; }
.contact-social-link:hover .contact-social-arrow { transform: translate(2px, -2px); color: var(--ink); }

.contact-form { display: flex; flex-direction: column; gap: .9rem; }
.contact-form-row { display: grid; grid-template-columns: 1fr 1fr; gap: .9rem; }
@media (max-width: 600px) { .contact-form-row { grid-template-columns: 1fr; } }
.contact-field { display: flex; flex-direction: column; gap: .35rem; }
.contact-label { font-family: var(--font-mono); font-size: .62rem; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; color: var(--silver); }
.contact-input, .contact-textarea {
  border: 1px solid var(--cloud); background: var(--snow);
  color: var(--ink); padding: .7rem .9rem; font-size: .85rem;
  font-family: var(--font-sans); outline: none; transition: border-color .15s;
}
.contact-input:focus, .contact-textarea:focus { border-color: var(--ink); }
.contact-textarea { min-height: 130px; resize: vertical; line-height: 1.6; }
.contact-submit { margin-top: .5rem; align-self: flex-start; }

.contact-success {
  display: flex; flex-direction: column; align-items: flex-start;
  gap: .75rem; padding: 2.5rem;
  border: 1px solid var(--cloud); background: var(--fog);
}
.contact-success-icon { font-size: 1.5rem; color: var(--ink); }
.contact-success-title { font-size: 1.1rem; font-weight: 800; color: var(--ink); }
.contact-success p { font-size: .85rem; color: var(--graphite); line-height: 1.7; }

/* ── Search overlay ──────────────────────────────────────────── */
.search-overlay {
  position: fixed; inset: 0; z-index: 500;
  background: rgba(10,10,10,.85); backdrop-filter: blur(6px);
  display: flex; align-items: flex-start; justify-content: center;
  padding: 10vh 1.5rem 0;
  opacity: 0; pointer-events: none; transition: opacity .2s;
}
.search-overlay.open { opacity: 1; pointer-events: all; }

.search-box {
  width: 100%; max-width: 680px;
  background: var(--white); border: 1px solid var(--cloud);
  display: flex; flex-direction: column;
  transform: translateY(-1rem); transition: transform .2s;
  max-height: 70vh; overflow: hidden;
}
.search-overlay.open .search-box { transform: none; }

.search-input-wrap {
  display: flex; align-items: center; gap: .85rem;
  padding: .9rem 1.25rem;
  border-bottom: 1px solid var(--cloud);
}
.search-input-wrap svg { color: var(--silver); flex-shrink: 0; }
.search-input {
  flex: 1; border: none; outline: none;
  font-size: 1rem; font-family: var(--font-sans);
  background: transparent; color: var(--ink);
}
.search-esc {
  font-family: var(--font-mono); font-size: .6rem;
  border: 1px solid var(--cloud); padding: .15rem .4rem;
  color: var(--mist); cursor: default;
}
.search-results {
  flex: 1; overflow-y: auto; padding: .5rem 0;
  min-height: 100px;
}
.search-result-section { padding: .25rem 1.25rem .1rem; font-family: var(--font-mono); font-size: .6rem; color: var(--mist); letter-spacing: .12em; text-transform: uppercase; margin-top: .5rem; }
.search-result-item {
  display: flex; align-items: flex-start; gap: .75rem;
  padding: .65rem 1.25rem; cursor: pointer; transition: background .1s;
}
.search-result-item:hover, .search-result-item.highlighted { background: var(--fog); }
.search-result-type { font-family: var(--font-mono); font-size: .6rem; color: var(--mist); width: 5rem; flex-shrink: 0; padding-top: .15rem; }
.search-result-name { font-size: .85rem; font-weight: 700; color: var(--ink); }
.search-result-sub { font-size: .75rem; color: var(--silver); margin-top: .1rem; }
.search-empty { padding: 2rem 1.25rem; font-size: .85rem; color: var(--mist); text-align: center; }
.search-footer {
  border-top: 1px solid var(--cloud); padding: .6rem 1.25rem;
  display: flex; gap: 1.5rem;
  font-family: var(--font-mono); font-size: .6rem; color: var(--mist);
}

/* ── SIGMA chat trigger button ───────────────────────────────── */
.sigma-trigger {
  position: fixed; bottom: 2rem; right: 2rem; z-index: 400;
  display: flex; align-items: center; gap: .65rem;
  background: var(--ink); color: var(--white);
  border: none; cursor: pointer;
  padding: .75rem 1.25rem .75rem .85rem;
  font-family: var(--font-sans); transition: all .2s;
  box-shadow: 0 4px 24px rgba(0,0,0,.35);
}
.sigma-trigger:hover { background: var(--ink-mid); box-shadow: 0 4px 32px rgba(0,0,0,.5); }
.sigma-trigger-ring {
  position: absolute; inset: -4px;
  border: 1px solid rgba(255,255,255,.12);
  animation: sigma-pulse 3s ease infinite;
}
@keyframes sigma-pulse {
  0%, 100% { opacity: .5; transform: scale(1); }
  50% { opacity: 0; transform: scale(1.06); }
}
.sigma-trigger-icon {
  font-size: 1.1rem; font-weight: 900;
  font-family: var(--font-mono);
  color: rgba(255,255,255,.9);
}
.sigma-trigger-label {
  font-size: .72rem; font-weight: 600; letter-spacing: .08em;
  text-transform: uppercase; color: rgba(255,255,255,.7);
}
@media (max-width: 480px) { .sigma-trigger-label { display: none; } }

/* ── SIGMA chat overlay ──────────────────────────────────────── */
.sigma-overlay {
  position: fixed; inset: 0; z-index: 600;
  background: var(--ink);
  display: flex; flex-direction: column;
  opacity: 0; pointer-events: none;
  transition: opacity .25s;
}
.sigma-overlay.open { opacity: 1; pointer-events: all; }

.sigma-grid-bg {
  position: absolute; inset: 0; opacity: .025;
  background-image: linear-gradient(rgba(255,255,255,1) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,1) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
}

.sigma-layout {
  position: relative; z-index: 1;
  display: flex; height: 100%;
}
@media (max-width: 768px) { .sigma-layout { flex-direction: column; } }

/* ── SIGMA left panel ────────────────────────────────────────── */
.sigma-left {
  width: 320px; flex-shrink: 0;
  border-right: 1px solid rgba(255,255,255,.07);
  padding: 2rem 1.75rem;
  display: flex; flex-direction: column; gap: 1.25rem;
  overflow-y: auto;
}
@media (max-width: 768px) {
  .sigma-left { width: 100%; border-right: none; border-bottom: 1px solid rgba(255,255,255,.07); padding: 1.25rem; flex-direction: row; flex-wrap: wrap; align-items: center; gap: .75rem; }
}

.sigma-brand { display: flex; align-items: center; gap: 1rem; }
.sigma-logo {
  width: 42px; height: 42px; background: var(--white);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-mono); font-size: 1.4rem; font-weight: 900;
  color: var(--ink); flex-shrink: 0;
}
.sigma-brand-name { font-size: .95rem; font-weight: 900; color: var(--white); letter-spacing: .06em; }
.sigma-brand-sub { font-family: var(--font-mono); font-size: .6rem; color: rgba(255,255,255,.3); margin-top: .1rem; }
.sigma-status { display: flex; align-items: center; gap: .4rem; margin-left: auto; }
.sigma-status-dot { width: 6px; height: 6px; border-radius: 50%; background: #2ecc71; animation: blink 2s ease infinite; }
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:.3} }
.sigma-status span { font-family: var(--font-mono); font-size: .6rem; color: rgba(255,255,255,.3); }

.sigma-description { font-size: .8rem; color: rgba(255,255,255,.4); line-height: 1.7; }
.sigma-divider { border: none; border-top: 1px solid rgba(255,255,255,.07); }

.sigma-suggestions-label { font-family: var(--font-mono); font-size: .6rem; letter-spacing: .15em; text-transform: uppercase; color: rgba(255,255,255,.2); }
.sigma-suggestions { display: flex; flex-direction: column; gap: .4rem; }
.sigma-suggest {
  background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.07);
  color: rgba(255,255,255,.55); font-size: .75rem; font-family: var(--font-sans);
  padding: .6rem .85rem; text-align: left; cursor: pointer; transition: all .15s;
  line-height: 1.4;
}
.sigma-suggest:hover { background: rgba(255,255,255,.08); color: var(--white); border-color: rgba(255,255,255,.15); }

.sigma-restriction {
  display: flex; align-items: flex-start; gap: .65rem;
  padding: .75rem; background: rgba(255,255,255,.03); border: 1px solid rgba(255,255,255,.06);
}
.sigma-restriction-icon { color: rgba(255,255,255,.2); font-size: .75rem; flex-shrink: 0; }
.sigma-restriction p { font-size: .72rem; color: rgba(255,255,255,.25); line-height: 1.5; }

/* ── SIGMA right chat panel ──────────────────────────────────── */
.sigma-right {
  flex: 1; display: flex; flex-direction: column; overflow: hidden;
}

.sigma-topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid rgba(255,255,255,.07);
  background: rgba(255,255,255,.02);
  flex-shrink: 0;
}
.sigma-topbar-title { font-family: var(--font-mono); font-size: .7rem; letter-spacing: .15em; text-transform: uppercase; color: rgba(255,255,255,.4); }
.sigma-topbar-limit { font-family: var(--font-mono); font-size: .62rem; color: rgba(255,255,255,.2); margin-top: .15rem; }
.sigma-close {
  width: 32px; height: 32px; background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.1); color: rgba(255,255,255,.5);
  font-size: 1.2rem; cursor: pointer; transition: all .15s; line-height: 1;
  display: flex; align-items: center; justify-content: center;
}
.sigma-close:hover { background: rgba(255,255,255,.12); color: var(--white); }

.sigma-messages {
  flex: 1; overflow-y: auto; padding: 1.5rem;
  display: flex; flex-direction: column; gap: 1rem;
  scroll-behavior: smooth;
}
.sigma-messages::-webkit-scrollbar { width: 3px; }
.sigma-messages::-webkit-scrollbar-track { background: transparent; }
.sigma-messages::-webkit-scrollbar-thumb { background: rgba(255,255,255,.1); }

.sigma-msg { display: flex; flex-direction: column; gap: .4rem; max-width: 82%; }
.sigma-msg--agent { align-self: flex-start; }
.sigma-msg--user { align-self: flex-end; align-items: flex-end; }

.sigma-msg-badge {
  font-family: var(--font-mono); font-size: .58rem; letter-spacing: .15em;
  color: rgba(255,255,255,.25); padding: .1rem .4rem;
  border: 1px solid rgba(255,255,255,.1); display: inline-block;
  align-self: flex-start;
}
.sigma-msg--user .sigma-msg-badge { color: rgba(255,255,255,.2); border-color: rgba(255,255,255,.08); align-self: flex-end; }

.sigma-msg-text {
  font-size: .83rem; line-height: 1.7; padding: .85rem 1rem;
  white-space: pre-wrap; word-break: break-word;
}
.sigma-msg--agent .sigma-msg-text {
  background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.08);
  color: rgba(255,255,255,.8); font-family: var(--font-mono);
  font-size: .78rem;
}
.sigma-msg--user .sigma-msg-text {
  background: var(--white); color: var(--ink);
  font-family: var(--font-sans);
}

/* Typing indicator */
.sigma-typing { display: flex; align-items: center; gap: .35rem; padding: .85rem 1rem; background: rgba(255,255,255,.04); border: 1px solid rgba(255,255,255,.08); align-self: flex-start; max-width: 80px; }
.sigma-typing span { width: 5px; height: 5px; border-radius: 50%; background: rgba(255,255,255,.3); animation: sigma-dot 1.4s ease infinite; }
.sigma-typing span:nth-child(2) { animation-delay: .2s; }
.sigma-typing span:nth-child(3) { animation-delay: .4s; }
@keyframes sigma-dot { 0%,80%,100%{transform:scale(.6);opacity:.3} 40%{transform:scale(1);opacity:1} }

.sigma-input-wrap {
  display: flex; align-items: flex-end; gap: .65rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid rgba(255,255,255,.07);
  background: rgba(255,255,255,.02); flex-shrink: 0;
}
.sigma-input {
  flex: 1; background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.1); color: var(--white);
  padding: .7rem 1rem; font-size: .83rem;
  font-family: var(--font-mono); outline: none; resize: none;
  line-height: 1.5; max-height: 120px; overflow-y: auto;
  transition: border-color .15s;
}
.sigma-input:focus { border-color: rgba(255,255,255,.25); }
.sigma-input::placeholder { color: rgba(255,255,255,.2); }
.sigma-send {
  width: 40px; height: 40px; flex-shrink: 0;
  background: var(--white); border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  color: var(--ink); transition: all .15s;
}
.sigma-send:hover { background: var(--fog); }
.sigma-send:disabled { background: rgba(255,255,255,.15); color: rgba(255,255,255,.3); cursor: not-allowed; }

/* Stop generation button */
.sigma-stop {
  width: 40px; height: 40px; flex-shrink: 0;
  background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.15);
  cursor: pointer; display: flex; align-items: center; justify-content: center;
  color: rgba(255,255,255,.6); transition: all .15s;
}
.sigma-stop:hover { background: rgba(255,80,80,.25); border-color: rgba(255,80,80,.4); color: #ff6b6b; }

/* ============================================================
   Admin styles
   ============================================================ */
.admin-layout { display: flex; min-height: 100vh; background: #111; }

.admin-sidebar {
  width: 220px; background: var(--ink); flex-shrink: 0;
  display: flex; flex-direction: column; overflow: hidden;
  transition: width .2s;
}
.admin-sidebar-logo { padding: 1.25rem 1rem; border-bottom: 1px solid var(--ink-muted); }
.admin-sidebar-logo .name { font-size: .82rem; font-weight: 800; color: var(--white); }
.admin-sidebar-logo .sub { font-family: var(--font-mono); font-size: .62rem; color: rgba(255,255,255,.3); margin-top: .1rem; }

.admin-nav { flex: 1; padding: .75rem 0; overflow-y: auto; }
.admin-nav-link {
  display: flex; align-items: center; gap: .75rem;
  padding: .65rem 1rem; font-size: .78rem; color: rgba(255,255,255,.5);
  cursor: pointer; transition: all .15s; border: none; background: none;
  width: 100%; text-align: left; font-family: var(--font-sans);
  border-left: 2px solid transparent;
  text-decoration: none;
}
.admin-nav-link:hover { color: var(--white); background: var(--ink-mid); }
.admin-nav-link.active { color: var(--white); background: var(--ink-muted); border-left-color: var(--white); }
.admin-nav-icon { font-size: .75rem; opacity: .6; width: 1rem; text-align: center; }

.admin-footer-links { border-top: 1px solid var(--ink-muted); padding: .5rem 0; }

.admin-main { flex: 1; display: flex; flex-direction: column; overflow: hidden; }
.admin-topbar {
  background: #1a1a1a; border-bottom: 1px solid #2a2a2a;
  padding: .9rem 2rem; display: flex; align-items: center; justify-content: space-between;
}
.admin-topbar h1 { font-size: .9rem; font-weight: 700; color: var(--white); }
.admin-topbar p { font-size: .65rem; font-family: var(--font-mono); color: rgba(255,255,255,.3); margin-top: .1rem; }
.admin-status { display: flex; align-items: center; gap: .5rem; font-family: var(--font-mono); font-size: .62rem; color: rgba(255,255,255,.3); }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: #2ecc71; }

.admin-content { flex: 1; overflow-y: auto; padding: 2rem; }
.admin-section-panel { max-width: 820px; }

/* Admin form elements */
.a-label { display: block; font-size: .68rem; font-weight: 600; text-transform: uppercase; letter-spacing: .08em; color: rgba(255,255,255,.4); margin-bottom: .4rem; }
.a-input, .a-textarea, .a-select {
  width: 100%; background: #1a1a1a; border: 1px solid #2a2a2a;
  color: var(--white); padding: .6rem .75rem; font-size: .82rem;
  font-family: var(--font-sans); outline: none;
  transition: border-color .15s;
}
.a-input:focus, .a-textarea:focus, .a-select:focus { border-color: rgba(255,255,255,.4); }
.a-textarea { resize: vertical; min-height: 80px; font-size: .78rem; line-height: 1.6; }
.a-select { cursor: pointer; }
.a-field { margin-bottom: 1rem; }
.a-row { display: grid; gap: .75rem; }
.a-row-2 { grid-template-columns: 1fr 1fr; }
.a-row-3 { grid-template-columns: 1fr 1fr 1fr; }
.a-checkbox { display: flex; align-items: center; gap: .5rem; cursor: pointer; }
.a-checkbox input { cursor: pointer; accent-color: white; }
.a-checkbox span { font-size: .78rem; color: rgba(255,255,255,.6); }

.a-card { background: #1a1a1a; border: 1px solid #2a2a2a; padding: 1.25rem; margin-bottom: .6rem; }
.a-card-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem; }
.a-card-title { font-size: .85rem; font-weight: 700; color: var(--white); line-height: 1.3; }
.a-card-sub { font-size: .72rem; color: rgba(255,255,255,.35); margin-top: .1rem; }
.a-card-actions { display: flex; gap: .25rem; flex-shrink: 0; }
.a-btn { font-size: .7rem; font-weight: 600; padding: .35rem .7rem; border: none; cursor: pointer; font-family: var(--font-sans); transition: all .15s; letter-spacing: .04em; }
.a-btn-edit { background: #2a2a2a; color: rgba(255,255,255,.7); }
.a-btn-edit:hover { background: #333; color: white; }
.a-btn-delete { background: transparent; color: rgba(255,255,255,.3); }
.a-btn-delete:hover { background: #c0392b; color: white; }
.a-btn-save { background: white; color: black; }
.a-btn-save:hover { background: #e8e8e8; }
.a-btn-cancel { background: transparent; color: rgba(255,255,255,.4); border: 1px solid #2a2a2a; }
.a-btn-cancel:hover { color: white; border-color: rgba(255,255,255,.3); }
.a-btn-add { background: white; color: black; font-size: .72rem; padding: .45rem 1rem; border: none; cursor: pointer; font-family: var(--font-sans); font-weight: 700; }
.a-btn-add:hover { background: #e8e8e8; }

.a-section-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1.25rem; }
.a-section-count { font-family: var(--font-mono); font-size: .65rem; color: rgba(255,255,255,.3); }

.a-add-form { background: #161616; border: 1px solid #2a2a2a; padding: 1.5rem; margin-bottom: 1rem; display: none; }
.a-add-form.open { display: block; }
.a-edit-form { background: #161616; border: 1px solid rgba(255,255,255,.1); padding: 1.5rem; margin-top: .5rem; }
.a-form-actions { display: flex; gap: .5rem; margin-top: 1.25rem; padding-top: 1rem; border-top: 1px solid #2a2a2a; }

.a-badge { font-family: var(--font-mono); font-size: .58rem; background: white; color: black; padding: .1rem .4rem; margin-left: .4rem; }

/* Toast */
#toast {
  position: fixed; bottom: 1.5rem; right: 1.5rem; z-index: 9999;
  background: white; color: var(--ink); padding: .75rem 1.25rem;
  font-size: .8rem; font-weight: 600;
  box-shadow: 0 4px 24px rgba(0,0,0,.25);
  opacity: 0; transform: translateY(.5rem);
  transition: all .25s;
  pointer-events: none;
}
#toast.show { opacity: 1; transform: none; }

/* Admin login */
.admin-login { min-height: 100vh; background: var(--ink); display: flex; align-items: center; justify-content: center; padding: 2rem; }
.login-box { width: 100%; max-width: 360px; }
.login-header { margin-bottom: 2.5rem; }
.login-header .pre { font-family: var(--font-mono); font-size: .62rem; letter-spacing: .3em; text-transform: uppercase; color: rgba(255,255,255,.25); margin-bottom: 1rem; }
.login-header h1 { font-size: 2rem; font-weight: 900; color: var(--white); letter-spacing: -.03em; }
.login-header p { font-size: .78rem; color: rgba(255,255,255,.35); margin-top: .35rem; }
.login-error { background: rgba(192,57,43,.2); border: 1px solid rgba(192,57,43,.4); color: #e74c3c; font-size: .78rem; padding: .65rem .85rem; margin-bottom: 1rem; }
.login-back { display: block; text-align: center; margin-top: 2rem; font-family: var(--font-mono); font-size: .62rem; color: rgba(255,255,255,.2); }
.login-back:hover { color: rgba(255,255,255,.5); }

/* ============================================================
   Mobile & Tablet Responsive
   ============================================================ */

/* ── Mobile nav toggle button ──────────────────────────────── */
.nav-toggle {
  display: none;
  flex-direction: column; justify-content: center; gap: 5px;
  width: 34px; height: 34px;
  background: transparent; border: none; cursor: pointer;
  padding: 4px; flex-shrink: 0;
}
@media (max-width: 768px) { .nav-toggle { display: flex; } }

.nav-toggle-bar {
  display: block; width: 22px; height: 1.5px;
  background: var(--white);
  transition: transform .25s ease, opacity .2s ease, background .25s;
  transform-origin: center;
}
.site-header.scrolled .nav-toggle-bar { background: var(--ink); }
.nav-toggle.open .nav-toggle-bar:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav-toggle.open .nav-toggle-bar:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-toggle.open .nav-toggle-bar:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

/* ── Mobile nav drawer ─────────────────────────────────────── */
.mobile-nav {
  position: absolute; top: 64px; left: 0; right: 0;
  background: rgba(10,10,10,.98); backdrop-filter: blur(12px);
  border-top: 1px solid rgba(255,255,255,.07);
  display: none;
  opacity: 0; transform: translateY(-6px);
  transition: opacity .2s ease, transform .2s ease;
  pointer-events: none;
}
@media (max-width: 768px) { .mobile-nav { display: block; } }
.mobile-nav.open { opacity: 1; transform: none; pointer-events: all; }
.site-header.scrolled .mobile-nav {
  background: rgba(250,250,250,.97);
  border-top-color: var(--cloud);
}

.mobile-nav .container {
  display: flex; flex-direction: column; padding-top: 1rem; padding-bottom: 1.5rem;
}
.mobile-nav a {
  display: block;
  font-size: 1rem; font-weight: 700; letter-spacing: -.01em;
  color: rgba(255,255,255,.65);
  padding: .8rem 0;
  border-bottom: 1px solid rgba(255,255,255,.06);
  transition: color .15s, padding-left .15s;
}
.mobile-nav a:last-child { border-bottom: none; }
.mobile-nav a:hover, .mobile-nav a.active { color: var(--white); padding-left: .5rem; }
.site-header.scrolled .mobile-nav a { color: var(--graphite); border-bottom-color: var(--cloud); }
.site-header.scrolled .mobile-nav a:hover,
.site-header.scrolled .mobile-nav a.active { color: var(--ink); }

/* ── Section padding ───────────────────────────────────────── */
@media (max-width: 768px) { .section { padding: 4rem 0; } }
@media (max-width: 480px) { .section { padding: 3rem 0; } }

/* ── Hero ──────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .hero { padding: 7rem 0 5rem; }
  .hero-pre span { font-size: .6rem; }
  .hero-role p { font-size: .82rem; }
  .hero-tagline { font-size: .9rem; margin-bottom: 2rem; }
  .hero-actions { gap: .75rem; }
  .hero-scroll { display: none; }
}

/* ── Impact strip ──────────────────────────────────────────── */
@media (max-width: 599px) {
  .impact-grid { grid-template-columns: repeat(2, 1fr); }
  .impact-cell { padding: 1.5rem 1.1rem; }
  .impact-metric { font-size: clamp(1.5rem, 7vw, 2rem); }
}

/* ── About section ─────────────────────────────────────────── */
@media (max-width: 768px) {
  .about-grid { gap: 2.5rem; }
  .profile-card { padding: 1.25rem; }
  .profile-meta-row { flex-direction: column; gap: .1rem; }
  .profile-meta-row .meta-val { text-align: left; }
}

/* ── Experience ────────────────────────────────────────────── */
@media (max-width: 768px) {
  .exp-layout { gap: 2rem; }
  .exp-sidebar-inner { position: static; }
  .exp-index { display: none; }
  .exp-timeline { padding-left: 1rem; }
  .exp-card { padding: 1.1rem; }
  .exp-role { font-size: .95rem; }
}

/* ── Projects ──────────────────────────────────────────────── */
@media (max-width: 768px) {
  .projects-group-toggle { flex-wrap: wrap; }
  .projects-filter { overflow-x: auto; flex-wrap: nowrap; padding-bottom: .5rem; -webkit-overflow-scrolling: touch; }
  .filter-btn { white-space: nowrap; flex-shrink: 0; }
}

/* ── Education + Certs ─────────────────────────────────────── */
@media (max-width: 768px) {
  .edu-certs-grid { gap: 2.5rem; }
  .edu-row { gap: .85rem; }
  .cert-row { flex-wrap: wrap; gap: .35rem; }
}

/* ── Contact ───────────────────────────────────────────────── */
@media (max-width: 768px) {
  .contact-layout { gap: 3rem; }
}

/* ── Search overlay ────────────────────────────────────────── */
@media (max-width: 600px) {
  .search-overlay { padding: 4vh .75rem 0; align-items: flex-start; }
  .search-box { max-height: 80vh; }
  .search-result-type { display: none; }
  .search-footer { display: none; }
}

/* ── SIGMA trigger ─────────────────────────────────────────── */
@media (max-width: 480px) {
  .sigma-trigger { bottom: 1.25rem; right: 1.25rem; padding: .65rem .85rem; }
}

/* ── SIGMA overlay ─────────────────────────────────────────── */
@media (max-width: 768px) {
  .sigma-layout { flex-direction: column; }
  .sigma-left {
    width: 100%; border-right: none;
    border-bottom: 1px solid rgba(255,255,255,.07);
    padding: 1rem 1.25rem;
    flex-direction: row; flex-wrap: wrap;
    align-items: center; gap: .75rem;
    flex-shrink: 0;
  }
  .sigma-description,
  .sigma-divider,
  .sigma-suggestions-label,
  .sigma-suggestions,
  .sigma-restriction { display: none; }
  .sigma-brand { flex-shrink: 0; }
  .sigma-status { margin-left: 0; }
  .sigma-messages { padding: 1rem; }
  .sigma-input-wrap { padding: .75rem 1rem; }
  .sigma-msg { max-width: 90%; }
  .sigma-topbar { padding: .75rem 1rem; }
}

/* ── Admin responsive ──────────────────────────────────────── */
@media (max-width: 768px) {
  .admin-layout { flex-direction: column; }
  .admin-sidebar {
    width: 100%; flex-direction: row; height: auto;
    overflow-x: auto; border-bottom: 1px solid var(--ink-muted);
  }
  .admin-sidebar-logo { padding: .75rem 1rem; border-bottom: none; border-right: 1px solid var(--ink-muted); flex-shrink: 0; }
  .admin-nav { display: flex; flex-direction: row; padding: 0; overflow-x: auto; flex: 1; }
  .admin-nav-link {
    flex-direction: column; gap: .2rem; padding: .6rem .75rem;
    font-size: .62rem; white-space: nowrap; border-left: none;
    border-bottom: 2px solid transparent; min-width: max-content;
  }
  .admin-nav-link.active { border-bottom-color: var(--white); border-left-color: transparent; }
  .admin-footer-links { display: none; }
  .admin-topbar { padding: .75rem 1rem; }
  .admin-content { padding: 1.25rem; }
  .a-row-2, .a-row-3 { grid-template-columns: 1fr; }
}

/* ── General tap target minimum ────────────────────────────── */
@media (max-width: 768px) {
  .btn, .filter-btn, .group-btn,
  .sigma-suggest, .contact-social-link { min-height: 44px; }
  .sigma-send, .sigma-stop, .sigma-close,
  .search-trigger, .nav-toggle { min-height: 44px; min-width: 44px; }
}