/* ===========================================================================
   Portfolio — Software Engineer & AI Engineer
   Hand-written CSS. No frameworks, no JavaScript.

   00  Design tokens
   01  Reset & base
   02  Typography primitives & utilities
   03  Layout shell & section furniture
   04  Header / navigation
   05  Buttons & links
   06  Hero + system diagram
   07  About
   08  Projects + per-project CSS visuals
   09  Expertise
   10  Experience & research
   11  Contact & footer
   12  Motion & accessibility preferences
   13  Responsive
   =========================================================================== */


/* ── 00  Design tokens ──────────────────────────────────────────────────── */
:root {
  /* palette */
  --bg:            #0B141A;
  --surface:       #101D25;
  --surface-2:     #0E1920;
  --text:          #EDEDED;
  --text-dim:      #A5B4BC;
  --cyan:          #23DEFF;
  --cyan-light:    #9AEDFF;
  --mint:          #B7FFD7;

  /* derived */
  --line:          rgba(165, 180, 188, 0.16);
  --line-strong:   rgba(165, 180, 188, 0.30);
  --line-faint:    rgba(165, 180, 188, 0.08);
  --cyan-dim:      rgba(35, 222, 255, 0.40);
  --cyan-ghost:    rgba(35, 222, 255, 0.08);
  --mint-ghost:    rgba(183, 255, 215, 0.10);

  /* type */
  --font-display: "Space Grotesk", "Helvetica Neue", Helvetica, Arial, sans-serif;
  --font-body:    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono:    "DM Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  /* rhythm */
  --shell:        1220px;
  --gutter:       clamp(20px, 5vw, 64px);
  --section-y:    clamp(72px, 10vw, 148px);
  --radius:       2px;

  /* motion */
  --ease:         cubic-bezier(0.22, 0.61, 0.36, 1);
  --fast:         160ms;
  --slow:         420ms;
}


/* ── 01  Reset & base ───────────────────────────────────────────────────── */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  background-color: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: clamp(0.95rem, 0.9rem + 0.2vw, 1.0625rem);
  font-weight: 300;
  line-height: 1.68;
  letter-spacing: 0.005em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ambient field: hairline grid + two very low-alpha accent washes */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--line-faint) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-faint) 1px, transparent 1px);
  background-size: 96px 96px;
  mask-image: radial-gradient(ellipse 120% 80% at 50% 0%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 120% 80% at 50% 0%, #000 0%, transparent 78%);
  opacity: 0.9;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(760px 420px at 88% -6%, rgba(35, 222, 255, 0.10), transparent 70%),
    radial-gradient(620px 420px at 2% 18%, rgba(183, 255, 215, 0.045), transparent 70%);
}

main,
.site-header,
.site-footer { position: relative; z-index: 1; }

img { max-width: 100%; display: block; }

::selection {
  background: rgba(35, 222, 255, 0.24);
  color: #fff;
}


/* ── 02  Typography primitives & utilities ──────────────────────────────── */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.04;
  letter-spacing: -0.028em;
  margin: 0;
  text-wrap: balance;
}

p { margin: 0 0 1.05em; }
p:last-child { margin-bottom: 0; }

.mono {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 400;
}

.dim { color: var(--text-dim); }
.sep { color: var(--line-strong); padding: 0 0.15em; }

/* placeholder marker — visible, intentional, easy to grep for */
.ph {
  border-bottom: 1px dashed rgba(183, 255, 215, 0.45);
  color: inherit;
}

.tech-line {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  line-height: 1.75;
  letter-spacing: 0.04em;
  color: var(--text-dim);
  margin-top: 0.9rem;
  word-break: break-word;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  background: var(--cyan);
  color: #04121a;
  padding: 10px 18px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-decoration: none;
}
.skip-link:focus { left: 12px; top: 12px; }


/* ── 03  Layout shell & section furniture ───────────────────────────────── */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }

.section + .section { border-top: 1px solid var(--line-faint); }

.section-head {
  display: grid;
  gap: 18px;
  margin-bottom: clamp(40px, 5vw, 72px);
}

.section-index {
  color: var(--cyan);
  margin: 0;
}

.section-title {
  font-size: clamp(1.85rem, 1.1rem + 2.6vw, 3rem);
  max-width: 20ch;
}

.section-rule {
  display: block;
  height: 1px;
  width: 100%;
  background: linear-gradient(90deg, var(--line-strong), transparent 62%);
}

.panel-label {
  color: var(--cyan);
  margin: 0 0 20px;
}


/* ── 04  Header / navigation ────────────────────────────────────────────── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(11, 20, 26, 0.78);
  backdrop-filter: saturate(140%) blur(14px);
  -webkit-backdrop-filter: saturate(140%) blur(14px);
  border-bottom: 1px solid var(--line-faint);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 68px;
  padding-block: 12px;
}

.monogram {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  flex-shrink: 0;
}

.monogram-mark {
  width: 14px;
  height: 14px;
  border: 1px solid var(--cyan);
  border-radius: 50%;
  position: relative;
  flex-shrink: 0;
}
.monogram-mark::after {
  content: "";
  position: absolute;
  inset: 4px;
  background: var(--mint);
  border-radius: 50%;
}

.monogram-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.06em;
}

.monogram-sub {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-dim);
  padding-left: 10px;
  border-left: 1px solid var(--line);
}

.site-nav ul {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 30px);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav a {
  position: relative;
  display: inline-block;
  padding: 6px 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
  text-decoration: none;
  transition: color var(--fast) var(--ease);
  white-space: nowrap;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform var(--slow) var(--ease);
}

.site-nav a:hover,
.site-nav a:focus-visible { color: var(--text); }

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}

.availability {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin: 0;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-dim);
  white-space: nowrap;
  flex-shrink: 0;
}

.pulse {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--mint);
  box-shadow: 0 0 0 0 rgba(183, 255, 215, 0.55);
  animation: pulse 2.6s var(--ease) infinite;
  flex-shrink: 0;
}

@keyframes pulse {
  0%   { box-shadow: 0 0 0 0 rgba(183, 255, 215, 0.5); }
  70%  { box-shadow: 0 0 0 7px rgba(183, 255, 215, 0); }
  100% { box-shadow: 0 0 0 0 rgba(183, 255, 215, 0); }
}


/* ── 05  Buttons & links ────────────────────────────────────────────────── */
.btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--text);
  background: transparent;
  overflow: hidden;
  transition: color var(--fast) var(--ease),
              border-color var(--fast) var(--ease),
              background-color var(--fast) var(--ease),
              transform var(--fast) var(--ease);
}

.btn-arrow { transition: transform var(--slow) var(--ease); }
.btn:hover .btn-arrow { transform: translateX(5px); }

.btn-primary {
  border-color: var(--cyan-dim);
  background: var(--cyan-ghost);
  color: var(--cyan-light);
}
.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--cyan);
  border-color: var(--cyan);
  color: #04121a;
}
.btn-primary:hover .ph,
.btn-primary:focus-visible .ph { border-bottom-color: rgba(4, 18, 26, 0.5); }

.btn-ghost { color: var(--text-dim); }
.btn-ghost:hover,
.btn-ghost:focus-visible {
  color: var(--text);
  border-color: var(--text-dim);
}

.btn-lg {
  padding: 17px 28px;
  font-size: clamp(0.78rem, 0.7rem + 0.3vw, 0.9rem);
  letter-spacing: 0.06em;
  text-transform: none;
}

.inline-link {
  color: var(--cyan-light);
  text-decoration: none;
  background-image: linear-gradient(var(--cyan), var(--cyan));
  background-size: 0% 1px;
  background-position: 0 100%;
  background-repeat: no-repeat;
  transition: background-size var(--slow) var(--ease), color var(--fast) var(--ease);
  padding-bottom: 1px;
}
.inline-link:hover,
.inline-link:focus-visible {
  background-size: 100% 1px;
  color: var(--cyan);
}

/* visible, non-clickable marker for a link that isn't known yet */
.link-pending {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-dim);
  opacity: 0.75;
}
.link-pending::before {
  content: "";
  width: 14px;
  height: 1px;
  background: var(--line-strong);
}

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 1px;
}


/* ── 06  Hero + system diagram ──────────────────────────────────────────── */
.hero {
  padding-block: clamp(56px, 8vw, 120px) clamp(72px, 10vw, 140px);
  overflow: hidden;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(0, 0.96fr);
  gap: clamp(40px, 6vw, 84px);
  align-items: center;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 0 0 26px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}
.eyebrow-rule {
  display: block;
  width: clamp(28px, 5vw, 56px);
  height: 1px;
  background: var(--cyan-dim);
}

.hero-title {
  font-size: clamp(2rem, 1.05rem + 5.2vw, 4.9rem);
  font-weight: 600;
  line-height: 0.98;
  letter-spacing: -0.035em;
  margin-bottom: 28px;
}

.title-accent {
  background: linear-gradient(96deg, var(--cyan) 0%, var(--cyan-light) 44%, var(--mint) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lede {
  max-width: 54ch;
  color: var(--text-dim);
  font-size: clamp(0.98rem, 0.92rem + 0.28vw, 1.1rem);
  line-height: 1.75;
  margin-bottom: 34px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: clamp(38px, 5vw, 56px);
}

.hero-meta {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line-faint);
  border-block: 1px solid var(--line-faint);
}

.hero-meta-item {
  background: var(--bg);
  padding: 16px 18px 16px 0;
}
.hero-meta-item + .hero-meta-item { padding-left: 18px; }

.hero-meta dt {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 7px;
}

.hero-meta dd {
  margin: 0;
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--text);
}

/* diagram shell */
.hero-visual { min-width: 0; }

.diagram {
  margin: 0;
  border: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(16, 29, 37, 0.92), rgba(11, 20, 26, 0.92));
  border-radius: var(--radius);
  overflow: hidden;
}

.diagram-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 11px 14px;
  border-bottom: 1px solid var(--line-faint);
  color: var(--text-dim);
}
.diagram-bar .mono { font-size: 0.625rem; letter-spacing: 0.12em; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.diagram-bar .dim { color: var(--mint); }

.diagram-stage {
  position: relative;
  aspect-ratio: 1 / 1;
  overflow: hidden;
}

.diagram-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line-faint) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-faint) 1px, transparent 1px);
  background-size: 11.11% 11.11%;
  opacity: 0.8;
}

.diagram-scan {
  position: absolute;
  left: 0;
  right: 0;
  height: 110px;
  background: linear-gradient(180deg, transparent, rgba(35, 222, 255, 0.07), transparent);
  animation: scan 7s linear infinite;
}
@keyframes scan {
  0%   { transform: translateY(-120px); }
  100% { transform: translateY(100%); }
}

/* edges */
.edge {
  position: absolute;
  height: 3px;
  margin-top: -1.5px;
  background:
    linear-gradient(90deg, rgba(35, 222, 255, 0.30), rgba(35, 222, 255, 0.14))
    center / 100% 1px no-repeat;
  transform-origin: 0 50%;
  overflow: hidden;
}
.edge::after {
  content: "";
  position: absolute;
  top: 0;
  left: -22%;
  width: 22%;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--cyan));
  animation: travel 3.4s linear infinite;
}
@keyframes travel {
  0%   { left: -22%; opacity: 0; }
  12%  { opacity: 1; }
  88%  { opacity: 1; }
  100% { left: 100%; opacity: 0; }
}

.edge-a { left: 12%; top: 50%; width: 38.2%; transform: rotate(-47.1deg); }
.edge-b { left: 12%; top: 50%; width: 38.2%; transform: rotate(47.1deg); }
.edge-c { left: 38%; top: 22%; width: 36.9%; transform: rotate(49.4deg); }
.edge-d { left: 38%; top: 78%; width: 36.9%; transform: rotate(-49.4deg); }
.edge-e { left: 62%; top: 50%; width: 31.8%; transform: rotate(-43.7deg); }
.edge-f { left: 62%; top: 50%; width: 31.8%; transform: rotate(43.7deg); }
.edge-g { left: 85%; top: 28%; width: 44%;   transform: rotate(90deg); }

.edge-a::after { animation-delay: 0s; }
.edge-b::after { animation-delay: 0.5s; }
.edge-c::after { animation-delay: 1.1s; }
.edge-d::after { animation-delay: 1.5s; }
.edge-e::after { animation-delay: 2.1s; }
.edge-f::after { animation-delay: 2.4s; }
.edge-g::after { animation-delay: 1.8s; }

/* nodes */
.node {
  position: absolute;
  transform: translate(-50%, -50%);
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 11px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(14, 25, 32, 0.94);
  font-family: var(--font-mono);
  font-size: clamp(0.56rem, 0.42rem + 0.4vw, 0.69rem);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-dim);
  white-space: nowrap;
}

.node-dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--cyan-dim);
  flex-shrink: 0;
}

.node.is-key {
  border-color: var(--cyan-dim);
  color: var(--cyan-light);
  background: rgba(16, 29, 37, 0.98);
}
.node.is-key .node-dot {
  background: var(--mint);
  animation: blink 2.4s ease-in-out infinite;
}
@keyframes blink {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.25; }
}

.node-query   { left: 12%; top: 50%; }
.node-embed   { left: 38%; top: 22%; }
.node-store   { left: 38%; top: 78%; }
.node-context { left: 62%; top: 50%; }
.node-llm     { left: 85%; top: 28%; }
.node-tools   { left: 85%; top: 72%; }

.stage-tag {
  position: absolute;
  color: var(--text-dim);
  opacity: 0.6;
  font-size: 0.6rem;
  letter-spacing: 0.1em;
}
.tag-tl { left: 14px; top: 12px; }
.tag-br { right: 14px; bottom: 12px; }

.diagram-foot {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  padding: 12px 14px;
  border-top: 1px solid var(--line-faint);
  color: var(--text-dim);
}
.diagram-foot .mono { font-size: 0.6rem; opacity: 0.8; }


/* ── 07  About ──────────────────────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.85fr);
  gap: clamp(36px, 5vw, 76px);
  align-items: start;
}

.about-narrative p { color: var(--text-dim); max-width: 62ch; }

.lead-para {
  color: var(--text) !important;
  font-size: clamp(1.05rem, 0.95rem + 0.5vw, 1.3rem);
  line-height: 1.6;
  font-weight: 300;
  letter-spacing: -0.012em;
  margin-bottom: 1.4em;
}

.about-closing {
  margin-top: 1.6em;
  padding-top: 1.4em;
  border-top: 1px solid var(--line-faint);
  color: var(--text) !important;
}

.about-profile {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(16, 29, 37, 0.7), rgba(16, 29, 37, 0.25));
  padding: clamp(22px, 2.4vw, 30px);
}

.profile-list { margin: 0; }

.profile-row {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  gap: 16px;
  padding: 11px 0;
  border-top: 1px solid var(--line-faint);
}
.profile-row:first-child { border-top: 0; padding-top: 0; }

.profile-row dt {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--cyan-light);
  line-height: 1.7;
}

.profile-row dd {
  margin: 0;
  font-size: 0.86rem;
  line-height: 1.6;
  color: var(--text-dim);
}

.profile-note {
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px solid var(--line-faint);
  font-size: 0.78rem;
  color: var(--text-dim);
}


/* ── 08  Projects ───────────────────────────────────────────────────────── */
.project-kicker {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 14px;
  color: var(--text-dim);
}

.status {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.status::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}
.status-build    { color: var(--mint); }
.status-proto    { color: var(--cyan-light); }
.status-explore  { color: var(--text-dim); }
.status-research { color: var(--cyan); }
.status-prod     { color: var(--mint); }

.project-title {
  font-size: clamp(1.35rem, 1rem + 1.3vw, 2.05rem);
  margin-bottom: 20px;
  line-height: 1.08;
}

.project-facts { margin: 0; display: grid; gap: 18px; }

.fact dt {
  color: var(--cyan);
  margin-bottom: 6px;
}
.fact dd {
  margin: 0;
  color: var(--text-dim);
  font-size: 0.92rem;
  line-height: 1.7;
  max-width: 56ch;
}

.fact-tag {
  color: var(--cyan);
  margin-right: 8px;
}

.project-problem,
.project-solution {
  color: var(--text-dim);
  font-size: 0.88rem;
  line-height: 1.7;
  margin-bottom: 0.9em;
}

.project-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px solid var(--line-faint);
}

/* -- featured ------------------------------------------------------------ */
.project-featured {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(0, 0.98fr);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(16, 29, 37, 0.78), rgba(11, 20, 26, 0.5));
  overflow: hidden;
  transition: border-color var(--slow) var(--ease);
}
.project-featured:hover { border-color: var(--line-strong); }

.featured-visual {
  border-right: 1px solid var(--line-faint);
  padding: clamp(20px, 2.4vw, 32px);
  display: flex;
}

.featured-body { padding: clamp(26px, 3vw, 44px); min-width: 0; }

/* -- two-up cards -------------------------------------------------------- */
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(18px, 2vw, 28px);
  margin-top: clamp(18px, 2vw, 28px);
}

.project-card {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(16, 29, 37, 0.42);
  overflow: hidden;
  transition: border-color var(--slow) var(--ease), transform var(--slow) var(--ease);
}
.project-card:hover {
  border-color: var(--line-strong);
  transform: translateY(-3px);
}

.card-visual {
  padding: clamp(18px, 2vw, 26px);
  border-bottom: 1px solid var(--line-faint);
}

.card-body { padding: clamp(22px, 2.4vw, 32px); min-width: 0; }

/* -- wide / horizontal --------------------------------------------------- */
.project-wide {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 0;
  margin-top: clamp(18px, 2vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(16, 29, 37, 0.3);
  overflow: hidden;
  transition: border-color var(--slow) var(--ease);
}
.project-wide:hover { border-color: var(--line-strong); }

.wide-visual {
  padding: clamp(20px, 2.4vw, 32px);
  border-right: 1px solid var(--line-faint);
  display: flex;
}
.wide-body { padding: clamp(24px, 2.8vw, 40px); min-width: 0; }

.project-wide.is-reversed .wide-visual {
  order: 2;
  border-right: 0;
  border-left: 1px solid var(--line-faint);
}
.project-wide.is-reversed .wide-body { order: 1; }

/* -- shared visual chrome ------------------------------------------------ */
.viz {
  position: relative;
  flex: 1;
  width: 100%;
  min-height: 210px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 16px;
  border: 1px solid var(--line-faint);
  border-radius: var(--radius);
  background: rgba(11, 20, 26, 0.72);
  overflow: hidden;
}

.viz-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, var(--line-faint) 1px, transparent 1px),
    linear-gradient(to bottom, var(--line-faint) 1px, transparent 1px);
  background-size: 28px 28px;
  opacity: 0.7;
  pointer-events: none;
}

.viz-label,
.viz-foot {
  position: relative;
  margin: 0;
  font-size: 0.58rem;
  letter-spacing: 0.14em;
  color: var(--text-dim);
}
.viz-label { color: var(--cyan); }
.viz-foot {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-top: auto;
  padding-top: 10px;
  border-top: 1px solid var(--line-faint);
  opacity: 0.8;
}

/* retrieval pipeline (featured) */
.viz-rag { gap: 18px; min-height: 300px; }

.rag-flow {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.rag-step {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 7px 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--text-dim);
  background: rgba(16, 29, 37, 0.9);
  white-space: nowrap;
}
.rag-step.is-store { border-color: var(--cyan-dim); color: var(--cyan-light); }
.rag-step.is-out   { border-color: rgba(183, 255, 215, 0.4); color: var(--mint); }

.rag-link {
  flex: 1 1 14px;
  min-width: 14px;
  height: 1px;
  background: var(--line-strong);
  position: relative;
  overflow: hidden;
}
.rag-link::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  transform: translateX(-100%);
  animation: slide 2.6s linear infinite;
}
.rag-link:nth-of-type(4)::after { animation-delay: 0.4s; }
.rag-link:nth-of-type(6)::after { animation-delay: 0.8s; }
.rag-link:nth-of-type(8)::after { animation-delay: 1.2s; }
@keyframes slide {
  0%   { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.rag-chunks {
  position: relative;
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 6px;
}
.chunk {
  height: 26px;
  border: 1px solid var(--line-faint);
  border-radius: 1px;
  background: rgba(165, 180, 188, 0.05);
}
.chunk.is-hit {
  border-color: var(--cyan-dim);
  background: var(--cyan-ghost);
  animation: hit 3.6s ease-in-out infinite;
}
.chunk.is-hit:nth-of-type(6)  { animation-delay: 0.6s; }
.chunk.is-hit:nth-of-type(10) { animation-delay: 1.2s; }
@keyframes hit {
  0%, 100% { background: var(--cyan-ghost); }
  50%      { background: rgba(35, 222, 255, 0.22); }
}

/* agent loop */
.agent-steps {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 16px;
  display: grid;
  gap: 8px;
}
.agent-steps::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line-strong);
}

.agent-step {
  position: relative;
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.06em;
  color: var(--text-dim);
  padding: 5px 9px;
  border: 1px solid transparent;
  border-radius: var(--radius);
}
.agent-step::before {
  content: "";
  position: absolute;
  left: -16px;
  top: 12px;
  width: 7px;
  height: 7px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: var(--bg);
}
.agent-step .mono { color: rgba(165, 180, 188, 0.5); margin-right: 6px; font-size: 0.6rem; }

.agent-step.is-active {
  border-color: var(--cyan-dim);
  background: var(--cyan-ghost);
  color: var(--cyan-light);
}
.agent-step.is-active::before {
  border-color: var(--cyan);
  background: var(--cyan);
  animation: blink 2.2s ease-in-out infinite;
}

.agent-loop {
  position: absolute;
  right: 18px;
  top: 54px;
  width: 34px;
  height: 108px;
  border: 1px solid var(--line);
  border-left: 0;
  border-radius: 0 40px 40px 0;
  opacity: 0.8;
}
.agent-loop::after {
  content: "";
  position: absolute;
  right: -3px;
  top: -3px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--mint);
  animation: blink 2.2s ease-in-out infinite;
}

/* kubernetes cluster */
.cluster-pods {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 7px;
}
.pod {
  aspect-ratio: 1 / 1;
  border: 1px solid var(--line-faint);
  border-radius: 1px;
  background: rgba(165, 180, 188, 0.04);
  position: relative;
}
.pod::after {
  content: "";
  position: absolute;
  inset: 35%;
  border-radius: 50%;
  background: rgba(165, 180, 188, 0.22);
}
.pod:nth-child(3n)::after  { background: var(--cyan-dim); }
.pod:nth-child(5n)::after  { background: rgba(183, 255, 215, 0.35); }
.pod.is-warn {
  border-color: rgba(35, 222, 255, 0.45);
  background: var(--cyan-ghost);
}
.pod.is-warn::after {
  background: var(--cyan);
  animation: blink 1.9s ease-in-out infinite;
}
.pod.is-warn:nth-child(12)::after { animation-delay: 0.7s; }

/* defect-likelihood matrix */
.matrix {
  position: relative;
  display: grid;
  grid-template-columns: repeat(8, minmax(0, 1fr));
  gap: 4px;
}
.cell {
  aspect-ratio: 1 / 1;
  border-radius: 1px;
  background: rgba(165, 180, 188, 0.07);
}
.cell:nth-child(3n)  { background: rgba(35, 222, 255, 0.12); }
.cell:nth-child(4n)  { background: rgba(35, 222, 255, 0.2); }
.cell:nth-child(7n)  { background: rgba(183, 255, 215, 0.24); }
.cell:nth-child(11n) { background: rgba(35, 222, 255, 0.42); }
.cell:nth-child(13n) { background: rgba(165, 180, 188, 0.04); }
.cell:nth-child(17n) {
  background: var(--cyan);
  animation: fade 4.2s ease-in-out infinite;
}
@keyframes fade {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.35; }
}

/* component-system wireframe */
.wire {
  position: relative;
  display: grid;
  gap: 8px;
  flex: 1;
}
.wire-bar {
  height: 16px;
  border: 1px solid var(--line);
  border-radius: 1px;
  background: rgba(165, 180, 188, 0.06);
}
.wire-main {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 8px;
  flex: 1;
}
.wire-side {
  border: 1px solid var(--line-faint);
  border-radius: 1px;
  background:
    repeating-linear-gradient(
      180deg,
      rgba(165, 180, 188, 0.14) 0 2px,
      transparent 2px 12px
    );
  min-height: 92px;
}
.wire-cards {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}
.wire-card {
  border: 1px solid var(--line-faint);
  border-radius: 1px;
  min-height: 42px;
  background:
    linear-gradient(180deg, rgba(165, 180, 188, 0.1) 0 6px, transparent 6px),
    rgba(165, 180, 188, 0.03);
}
.wire-card.is-live {
  border-color: var(--cyan-dim);
  background:
    linear-gradient(180deg, rgba(35, 222, 255, 0.28) 0 6px, transparent 6px),
    var(--cyan-ghost);
  animation: hit 4s ease-in-out infinite;
}


/* ── 09  Expertise ──────────────────────────────────────────────────────── */
.expertise-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-faint);
  border: 1px solid var(--line-faint);
}

.expertise-col {
  background: var(--bg);
  padding: clamp(22px, 2.4vw, 32px);
  transition: background-color var(--slow) var(--ease);
}
.expertise-col:hover { background: rgba(16, 29, 37, 0.6); }

.col-index {
  color: var(--cyan);
  opacity: 0.7;
  margin: 0 0 14px;
}

.col-title {
  font-size: 1.1rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.skill-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 9px;
}
.skill-list li {
  position: relative;
  padding-left: 16px;
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--text-dim);
  transition: color var(--fast) var(--ease);
}
.skill-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 7px;
  height: 1px;
  background: var(--cyan-dim);
  transition: width var(--slow) var(--ease), background-color var(--fast) var(--ease);
}
.expertise-col:hover .skill-list li { color: var(--text); }
.expertise-col:hover .skill-list li::before { width: 11px; background: var(--cyan); }

.expertise-note {
  margin: 26px 0 0;
  color: var(--text-dim);
  opacity: 0.7;
  font-size: 0.64rem;
  letter-spacing: 0.1em;
  text-transform: none;
}


/* ── 10  Experience & research ──────────────────────────────────────────── */
.timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-faint);
}

.timeline-item {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: clamp(20px, 3vw, 48px);
  padding: clamp(24px, 3vw, 38px) 0;
  border-bottom: 1px solid var(--line-faint);
  transition: background-color var(--slow) var(--ease);
}
.timeline-item:hover { background: rgba(16, 29, 37, 0.35); }

.timeline-period {
  margin: 0;
  padding-top: 5px;
  color: var(--cyan);
  letter-spacing: 0.12em;
  align-self: start;
}

.timeline-body { min-width: 0; }

.timeline-role {
  font-size: clamp(1.1rem, 0.95rem + 0.6vw, 1.45rem);
  font-weight: 500;
  margin-bottom: 8px;
  line-height: 1.22;
}
.timeline-role .at {
  color: var(--text-dim);
  font-weight: 400;
  font-family: var(--font-body);
  font-size: 0.75em;
  padding: 0 2px;
}

.timeline-type {
  color: var(--text-dim);
  opacity: 0.75;
  margin: 0 0 12px;
  font-size: 0.62rem;
}

.timeline-body p { color: var(--text-dim); font-size: 0.9rem; max-width: 62ch; }

.timeline-note {
  margin-top: 24px;
  font-size: 0.8rem;
  color: var(--text-dim);
  opacity: 0.8;
}


/* ── 11  Contact & footer ───────────────────────────────────────────────── */
.section-contact {
  border-top: 1px solid var(--line-faint);
  background:
    radial-gradient(900px 420px at 50% 120%, rgba(35, 222, 255, 0.09), transparent 70%);
}

.contact-inner {
  display: grid;
  justify-items: start;
  gap: 0;
}

.contact-title {
  font-size: clamp(2.1rem, 1.1rem + 4vw, 4.1rem);
  line-height: 1;
  margin: 18px 0 26px;
  letter-spacing: -0.035em;
}

.contact-lede {
  max-width: 56ch;
  color: var(--text-dim);
  font-size: clamp(0.98rem, 0.92rem + 0.28vw, 1.08rem);
  margin-bottom: 34px;
}

.contact-cta { margin-bottom: clamp(36px, 5vw, 56px); }

.contact-links {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  width: 100%;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line-faint);
  border-block: 1px solid var(--line-faint);
}

.contact-link {
  display: grid;
  gap: 8px;
  background: var(--bg);
  padding: 20px 18px 20px 0;
  text-decoration: none;
  color: var(--text);
  transition: background-color var(--fast) var(--ease);
  word-break: break-word;
}
.contact-links li + li .contact-link { padding-left: 18px; }
.contact-link:hover { background: rgba(16, 29, 37, 0.8); }

.contact-link-label {
  color: var(--text-dim);
  font-size: 0.62rem;
}
.contact-link-value {
  font-family: var(--font-display);
  font-size: clamp(0.9rem, 0.82rem + 0.3vw, 1.05rem);
  letter-spacing: -0.015em;
  color: var(--text);
  transition: color var(--fast) var(--ease);
  justify-self: start;
}
.contact-link:hover .contact-link-value,
.contact-link:focus-visible .contact-link-value { color: var(--cyan-light); }

.contact-note {
  color: var(--text-dim);
  opacity: 0.6;
  text-transform: none;
  letter-spacing: 0.06em;
  font-size: 0.68rem;
}

.site-footer {
  border-top: 1px solid var(--line-faint);
  padding-block: 28px;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px 28px;
}

.footer-identity {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 500;
}

.footer-meta {
  margin: 0;
  color: var(--text-dim);
  opacity: 0.65;
  font-size: 0.62rem;
  text-transform: none;
  letter-spacing: 0.08em;
}

.footer-top { margin: 0; font-size: 0.8rem; }


/* ── 12  Motion & accessibility preferences ─────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .project-card:hover { transform: none; }
}


/* ── 13  Responsive ─────────────────────────────────────────────────────── */

/* laptop */
@media (max-width: 1080px) {
  .hero-grid { grid-template-columns: minmax(0, 1fr); gap: 48px; }
  .hero-visual { max-width: 540px; width: 100%; }
  .hero-title { max-width: 14ch; }

  .project-featured { grid-template-columns: minmax(0, 1fr); }
  .featured-visual { border-right: 0; border-bottom: 1px solid var(--line-faint); }

  .expertise-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* tablet */
@media (max-width: 900px) {
  .about-grid { grid-template-columns: minmax(0, 1fr); }

  .project-grid { grid-template-columns: minmax(0, 1fr); }

  .project-wide,
  .project-wide.is-reversed { grid-template-columns: minmax(0, 1fr); }
  .wide-visual,
  .project-wide.is-reversed .wide-visual {
    order: 1;
    border-right: 0;
    border-left: 0;
    border-bottom: 1px solid var(--line-faint);
  }
  .wide-body,
  .project-wide.is-reversed .wide-body { order: 2; }

  .timeline-item { grid-template-columns: minmax(0, 1fr); gap: 10px; }
  .timeline-period { padding-top: 0; }
}

/* small tablet / large phone */
@media (max-width: 760px) {
  .header-inner {
    flex-wrap: wrap;
    row-gap: 10px;
    padding-block: 10px;
  }
  .monogram-sub { display: none; }
  .site-nav {
    order: 3;
    width: 100%;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
    border-top: 1px solid var(--line-faint);
    padding-top: 8px;
  }
  .site-nav::-webkit-scrollbar { display: none; }
  .site-nav ul { gap: 18px; padding-bottom: 2px; }

  html { scroll-padding-top: 116px; }

  .hero-meta { grid-template-columns: minmax(0, 1fr); }
  .hero-meta-item,
  .hero-meta-item + .hero-meta-item {
    padding: 13px 0;
    border-top: 1px solid var(--line-faint);
  }
  .hero-meta-item:first-child { border-top: 0; }

  .contact-links { grid-template-columns: minmax(0, 1fr); }
  .contact-link,
  .contact-links li + li .contact-link {
    padding: 16px 0;
    border-top: 1px solid var(--line-faint);
  }
  .contact-links li:first-child .contact-link { border-top: 0; }

  .agent-loop { display: none; }
}

/* phone */
@media (max-width: 560px) {
  .expertise-grid { grid-template-columns: minmax(0, 1fr); }

  .profile-row { grid-template-columns: minmax(0, 1fr); gap: 4px; }

  .hero-actions .btn { flex: 1 1 100%; justify-content: center; }

  .rag-chunks { grid-template-columns: repeat(4, minmax(0, 1fr)); }

  .footer-inner { justify-content: flex-start; }

  .section-title { max-width: none; }
}

/* very small phone */
@media (max-width: 380px) {
  :root { --gutter: 16px; }

  .availability { display: none; }

  .node {
    font-size: 0.52rem;
    padding: 5px 7px;
    gap: 5px;
  }

  .viz { padding: 12px; }

  .btn { width: 100%; justify-content: center; }
}