/* ============================================================
   POB — design tokens
   ============================================================ */
:root {
  --crimson: #C3011E;
  --crimson-dim: #7A0113;

  /* dark theme (default) */
  --bg: #0D0D0D;
  --bg-panel: #131313;
  --bg-panel-alt: #1A1A1A;
  --border: #333333;
  --border-soft: #232323;
  --text: #FFFFFF;
  --text-dim: #9A9A9A;
  --text-faint: #6E6E6E;
  --offset: #232323;
  --grid-line: rgba(255, 255, 255, 0.035);

  --font-display: 'Silkscreen', 'Courier New', monospace;
  --font-mono: 'JetBrains Mono', 'IBM Plex Mono', ui-monospace, monospace;

  --unit: 8px;
  --gap: clamp(16px, 2.4vw, 32px);
  --max: 1240px;
  --edge: clamp(20px, 5vw, 64px);
}

:root[data-theme="light"] {
  --bg: #FFFFFF;
  --bg-panel: #F5F5F3;
  --bg-panel-alt: #EBEBE8;
  --border: #CFCECA;
  --border-soft: #E3E2DE;
  --text: #0D0D0D;
  --text-dim: #55534E;
  --text-faint: #8A887F;
  --offset: #CFCECA;
  --grid-line: rgba(13, 13, 13, 0.05);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  transition: background 0.2s ease, color 0.2s ease;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; margin: 0; padding: 0; }
h1, h2, h3, h4 { margin: 0; font-weight: 400; }

::selection { background: var(--crimson); color: #FFFFFF; }

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============================================================
   Background grid — faint structural lattice
   ============================================================ */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 30%, transparent 85%);
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 30%, transparent 85%);
}

.container {
  position: relative;
  z-index: 1;
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--edge);
}

/* ============================================================
   Utility: technical annotation labels
   ============================================================ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
  border: 1px solid var(--border);
  padding: 4px 10px;
}
.tag::before { content: '//'; color: var(--crimson); }

.section-index {
  font-family: var(--font-display);
  font-size: 13px;
  color: var(--crimson);
  letter-spacing: 0.05em;
}

/* ============================================================
   PCB trace dividers
   ============================================================ */
.trace {
  position: relative;
  width: 100%;
  height: 24px;
  z-index: 1;
}
.trace svg { width: 100%; height: 100%; overflow: visible; }
.trace-line { stroke: var(--border); stroke-width: 1.5; fill: none; }
.trace-node { fill: var(--bg); stroke: var(--crimson); stroke-width: 1.5; }

/* ============================================================
   Nav
   ============================================================ */
.site-nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 92%, transparent);
  border-bottom: 1px solid var(--border-soft);
}
.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.nav-logo {
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: 0.02em;
  display: flex;
  align-items: center;
  gap: 8px;
}
.nav-logo img { image-rendering: pixelated; }

.nav-links {
  display: flex;
  gap: clamp(16px, 3vw, 40px);
  font-size: 12px;
  letter-spacing: 0.08em;
}
.nav-links a {
  color: var(--text-dim);
  position: relative;
  padding: 4px 2px;
  transition: color 0.15s ease;
}
.nav-links a .idx { color: var(--crimson); margin-right: 4px; }
.nav-links a:hover, .nav-links a.is-active { color: var(--text); }

.nav-right { display: flex; align-items: center; gap: 12px; }

.nav-gh {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--text-dim);
  transition: border-color 0.15s ease, color 0.15s ease, transform 0.15s ease;
}
.nav-gh:hover {
  border-color: var(--crimson);
  color: var(--text);
  transform: translate(-1px, -1px);
}

/* Theme toggle — DIP-switch style */
.theme-toggle {
  display: flex;
  border: 1px solid var(--border);
}
.theme-btn {
  width: 30px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
  background: transparent;
  color: var(--text-faint);
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}
.theme-btn svg { width: 13px; height: 13px; fill: currentColor; overflow: visible; }
.theme-btn:first-child { border-right: 1px solid var(--border); }
.theme-btn[aria-pressed="true"] {
  background: var(--crimson);
  color: #FFFFFF;
}
.theme-btn:not([aria-pressed="true"]):hover { color: var(--text); }

/* ============================================================
   Buttons — hard-edged pixel offset shadow, no blur/glow
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 13px 22px;
  border: 1.5px solid var(--text);
  background: transparent;
  color: var(--text);
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease, color 0.12s ease, border-color 0.12s ease;
}
.btn-primary {
  background: var(--crimson);
  border-color: var(--crimson);
  color: #FFFFFF;
  box-shadow: 4px 4px 0 0 var(--offset);
}
.btn-primary:hover { transform: translate(-2px, -2px); box-shadow: 6px 6px 0 0 var(--offset); }
.btn-ghost { box-shadow: 4px 4px 0 0 var(--offset); }
.btn-ghost:hover {
  border-color: var(--crimson);
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 0 var(--offset);
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  padding: 148px 0 96px;
  position: relative;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: clamp(32px, 6vw, 80px);
  align-items: center;
}
@media (max-width: 880px) {
  .hero-grid { grid-template-columns: 1fr; }
}

.prompt-line {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.prompt-line .sym { color: var(--crimson); }
.cursor {
  display: inline-block;
  width: 8px;
  height: 15px;
  background: var(--crimson);
  animation: blink 1.1s steps(1) infinite;
  vertical-align: -2px;
}
@keyframes blink { 50% { opacity: 0; } }

.hero-wordmark {
  width: min(100%, 420px);
  height: auto;
  margin-bottom: 20px;
}

.hero-role {
  font-family: var(--font-display);
  font-size: clamp(16px, 2vw, 20px);
  color: var(--crimson);
  margin: 0 0 16px;
  letter-spacing: 0.02em;
}

.hero-desc {
  max-width: 46ch;
  color: var(--text-dim);
  font-size: 14.5px;
  margin-bottom: 32px;
}
.hero-desc b { color: var(--text); font-weight: 500; }

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 36px;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 16px; }

/* Terminal window mock */
.term-window {
  border: 1px solid var(--border);
  background: var(--bg-panel);
  position: relative;
}
.term-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border-soft);
  background: var(--bg-panel-alt);
}
.term-dots { display: flex; gap: 6px; }
.term-dots span { width: 8px; height: 8px; border: 1px solid var(--text-faint); }
.term-dots span:nth-child(1) { border-color: var(--crimson); }
.term-title { font-size: 11px; color: var(--text-faint); letter-spacing: 0.08em; }
.term-body { padding: 20px 18px; font-size: 13px; }
.term-row { display: flex; gap: 10px; margin-bottom: 9px; }
.term-row:last-child { margin-bottom: 0; }
.term-key { color: var(--text-faint); min-width: 76px; flex-shrink: 0; }
.term-val { color: var(--text); }
.term-val.accent { color: var(--crimson); }
.term-prompt { color: var(--text-faint); }
.term-cmd { color: var(--text); }

/* ============================================================
   Section shell
   ============================================================ */
.section { padding: 88px 0; position: relative; }
.section-head {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 48px;
}
.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(20px, 2.6vw, 28px);
  letter-spacing: 0.02em;
}
.section-head .line {
  flex: 1;
  height: 1px;
  background: var(--border-soft);
}

.reveal { opacity: 0; transform: translateY(14px); transition: opacity 0.5s ease, transform 0.5s ease; }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ============================================================
   About
   ============================================================ */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap);
}
@media (max-width: 880px) { .about-grid { grid-template-columns: 1fr; } }

.about-copy p { color: var(--text-dim); margin: 0 0 16px; font-size: 14.5px; }
.about-copy p:last-child { margin-bottom: 0; }
.about-copy .lead { color: var(--text); font-size: 16px; }
.about-copy a { color: var(--text); text-decoration: underline; text-decoration-color: var(--border); }

.info-panel {
  border: 1px solid var(--border);
  background: var(--bg-panel);
}
.info-panel-head {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border-soft);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--text-faint);
  text-transform: uppercase;
}
.info-row {
  display: flex;
  justify-content: space-between;
  padding: 13px 16px;
  border-bottom: 1px solid var(--border-soft);
  font-size: 13px;
}
.info-row:last-child { border-bottom: none; }
.info-row .k { color: var(--text-faint); }
.info-row .v { color: var(--text); text-align: right; }
.info-row .v.accent { color: var(--crimson); }
.led {
  display: inline-block;
  width: 7px; height: 7px;
  background: var(--crimson);
  margin-right: 6px;
  animation: pulse 2.2s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.35; } }

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

.project-card {
  position: relative;
  border: 1px solid var(--border);
  background: var(--bg-panel);
  padding: 22px;
  display: flex;
  flex-direction: column;
  min-height: 240px;
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}
.project-card:hover {
  border-color: var(--crimson);
  transform: translate(-3px, -3px);
  box-shadow: 5px 5px 0 0 var(--offset);
}
.project-node {
  position: absolute;
  width: 7px; height: 7px;
  background: var(--bg);
  border: 1.5px solid var(--border);
}
.project-card:hover .project-node { border-color: var(--crimson); }
.project-node.tl { top: -4px; left: -4px; }
.project-node.tr { top: -4px; right: -4px; }
.project-node.bl { bottom: -4px; left: -4px; }
.project-node.br { bottom: -4px; right: -4px; }

.project-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.project-idx { font-family: var(--font-display); font-size: 11px; color: var(--text-faint); }
.project-fork { font-size: 10px; letter-spacing: 0.08em; color: var(--text-faint); border: 1px solid var(--border-soft); padding: 2px 6px; }

.project-title {
  font-family: var(--font-display);
  font-size: 17px;
  margin-bottom: 10px;
  letter-spacing: 0.01em;
}
.project-desc { color: var(--text-dim); font-size: 13.5px; flex: 1; margin-bottom: 18px; }

.project-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 16px; }
.chip {
  font-size: 10.5px;
  letter-spacing: 0.05em;
  color: var(--text-dim);
  border: 1px solid var(--border-soft);
  padding: 3px 8px;
}

.project-link {
  font-size: 12.5px;
  color: var(--text);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border-top: 1px solid var(--border-soft);
  padding-top: 12px;
  transition: color 0.15s ease, gap 0.15s ease;
}
.project-link .arrow { color: var(--crimson); }
.project-link:hover { color: var(--crimson); }

/* ============================================================
   Stack
   ============================================================ */
.stack-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 1px;
  background: var(--border-soft);
  border: 1px solid var(--border-soft);
}
.stack-chip {
  background: var(--bg-panel);
  padding: 20px 14px;
  text-align: center;
  position: relative;
}
.stack-chip .pin {
  position: absolute;
  width: 10px;
  height: 2px;
  background: var(--border);
}
.stack-chip .pin.l { left: -10px; top: 50%; transform: translateY(-50%); }
.stack-chip .pin.r { right: -10px; top: 50%; transform: translateY(-50%); }
.stack-chip-label {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.03em;
  color: var(--text-dim);
}
.stack-chip:hover .stack-chip-label { color: var(--text); }
.stack-chip:hover { background: var(--bg-panel-alt); }

/* ============================================================
   Contact
   ============================================================ */
.contact-panel {
  border: 1px solid var(--border);
  background: var(--bg-panel);
}
.contact-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border-soft);
  transition: background 0.15s ease;
}
.contact-row:last-child { border-bottom: none; }
.contact-row:hover { background: var(--bg-panel-alt); }
.contact-left { display: flex; align-items: center; gap: 14px; }
.contact-cmd { color: var(--text-faint); font-size: 13px; }
.contact-target { font-size: 14.5px; color: var(--text); font-family: var(--font-mono); }
.contact-arrow { color: var(--crimson); font-size: 15px; transition: transform 0.15s ease; }
.contact-row:hover .contact-arrow { transform: translateX(4px); }

/* ============================================================
   Footer
   ============================================================ */
.site-footer { padding: 40px 0 56px; }
.footer-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 11.5px;
  color: var(--text-faint);
  letter-spacing: 0.04em;
}
.footer-status { display: flex; align-items: center; gap: 8px; }
.footer-status .led { animation: pulse 2.2s ease-in-out infinite; }

/* ============================================================
   Responsive nav collapse
   ============================================================ */
@media (max-width: 720px) {
  .nav-links { display: none; }
}