/* =========================================================
   RAYEN HAJJEM — PORTFOLIO
   Design system: "Datasheet / PCB substrate"
   ========================================================= */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600;700;800&family=Inter:wght@400;500;600;700;800&display=swap');

:root{
  /* --- colour tokens --- */
  --bg:            #0a0e12;
  --bg-soft:       #0d1218;
  --surface:       #10161d;
  --surface-2:     #141b23;
  --line:          #212a33;
  --line-soft:     #1a222a;
  --copper:        #c97a4a;
  --copper-bright: #e2996a;
  --signal:        #4fd8c4;
  --signal-dim:    #2c7d72;
  --amber:         #e8a33d;
  --text:          #e8edf0;
  --text-dim:      #8b97a3;
  --text-faint:    #566270;
  --danger:        #d9634f;

  --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;
  --sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --maxw: 1120px;
  --radius: 3px;
}

*, *::before, *::after{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }
html, body{ margin:0; padding:0; }

body{
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  position: relative;
  min-height: 100vh;
}

/* faint PCB grid + via dots painted on the substrate */
body::before{
  content:"";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(79,216,196,0.07) 1px, transparent 1px),
    linear-gradient(rgba(255,255,255,0.018) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.018) 1px, transparent 1px);
  background-size: 44px 44px, 44px 44px, 44px 44px;
  background-position: 0 0, 0 0, 0 0;
}

a{ color: inherit; text-decoration: none; }
img{ max-width: 100%; display:block; }
ul{ list-style: none; margin:0; padding:0; }

::selection{ background: var(--signal); color: #05201c; }

/* focus visibility */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible{
  outline: 2px solid var(--signal);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce){
  *{ animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; scroll-behavior: auto !important; }
}

/* ---------- layout shell ---------- */
.wrap{
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 28px;
  position: relative;
  z-index: 1;
}

/* ---------- eyebrow / mono labels ---------- */
.eyebrow{
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--copper);
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 14px;
}
.eyebrow::before{
  content:"";
  width: 8px; height: 8px;
  border: 1.5px solid var(--copper);
  border-radius: 1px;
  transform: rotate(45deg);
  flex-shrink: 0;
}

h1,h2,h3,h4{
  font-family: var(--mono);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text);
  margin: 0;
  text-transform: uppercase;
}
h1{ font-size: clamp(34px, 5.6vw, 58px); line-height: 1.05; letter-spacing: -0.01em; }
h2{ font-size: clamp(24px, 3.2vw, 32px); }
h3{ font-size: 17px; letter-spacing: .01em; }

p{ color: var(--text-dim); margin: 0 0 1em; max-width: 62ch; }
.lede{ font-size: 18px; color: var(--text-dim); max-width: 58ch; }

/* ---------- top nav (board header) ---------- */
.topbar{
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10,14,18,0.86);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar-inner{
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 28px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand{
  font-family: var(--mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: .04em;
  display: flex;
  align-items: baseline;
  gap: 8px;
}
.brand .part-no{ color: var(--text-faint); font-weight: 500; font-size: 11px; }
.brand .dot{ color: var(--signal); }

.navlinks{
  display: flex;
  align-items: center;
  gap: 4px;
}
.navlinks a{
  position: relative;
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--text-dim);
  padding: 10px 14px;
  transition: color .18s ease;
}
.navlinks a:hover{ color: var(--text); }
.navlinks a.active{ color: var(--signal); }
.navlinks a.active::after{
  content:"";
  position: absolute;
  left: 14px; right: 14px; bottom: 4px;
  height: 1px;
  background: var(--signal);
  box-shadow: 0 0 6px var(--signal);
}
.navlinks a.active::before{
  content:"";
  position: absolute;
  left: 50%; bottom: 2px;
  width: 4px; height: 4px;
  transform: translateX(-50%);
  background: var(--signal);
  border-radius: 50%;
  box-shadow: 0 0 6px var(--signal);
}

.navcta{
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: .08em;
  text-transform: uppercase;
  border: 1px solid var(--copper);
  color: var(--copper-bright);
  padding: 8px 14px;
  border-radius: var(--radius);
  transition: background .18s ease, color .18s ease;
}
.navcta:hover{ background: var(--copper); color: #14100c; }

.menu-toggle{
  display: none;
  background: none; border: 1px solid var(--line);
  color: var(--text);
  width: 40px; height: 40px;
  border-radius: var(--radius);
  align-items: center; justify-content: center;
  cursor: pointer;
}
.menu-toggle svg{ width: 18px; height: 18px; }

@media (max-width: 820px){
  .navlinks{
    position: fixed;
    inset: 68px 0 0 0;
    background: var(--bg-soft);
    flex-direction: column;
    align-items: stretch;
    padding: 10px 20px 30px;
    border-bottom: 1px solid var(--line);
    display: none;
    gap: 0;
  }
  .navlinks.open{ display: flex; }
  .navlinks a{ padding: 16px 4px; border-bottom: 1px solid var(--line-soft); }
  .navlinks a.active::after, .navlinks a.active::before{ display:none; }
  .navcta{ display:none; }
  .menu-toggle{ display: flex; }
}

/* ---------- sections ---------- */
section{ position: relative; z-index: 1; padding: 96px 0; border-bottom: 1px solid var(--line-soft); }
section:last-of-type{ border-bottom: none; }
.section-head{ margin-bottom: 48px; max-width: 640px; }

/* ---------- hero ---------- */
.hero{
  padding: 84px 0 90px;
  position: relative;
  overflow: hidden;
}
.hero-grid{
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}
@media (max-width: 900px){ .hero-grid{ grid-template-columns: 1fr; } }

.terminal{
  font-family: var(--mono);
  font-size: 13.5px;
  color: var(--signal);
  margin-bottom: 22px;
  min-height: 20px;
}
.terminal .caret{
  display:inline-block; width:8px; height:14px;
  background: var(--signal); margin-left:2px;
  animation: blink 1s steps(1) infinite;
  vertical-align: -2px;
}
@keyframes blink{ 50%{ opacity:0; } }

.hero h1 span{ color: var(--signal); }
.hero-role{
  font-family: var(--mono);
  font-size: 14px;
  letter-spacing: .04em;
  color: var(--copper-bright);
  margin: 16px 0 20px;
  text-transform: uppercase;
}
.hero-actions{ display:flex; gap:14px; margin-top: 30px; flex-wrap: wrap; }

.btn{
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: .06em;
  text-transform: uppercase;
  padding: 13px 22px;
  border-radius: var(--radius);
  display: inline-flex; align-items:center; gap:10px;
  transition: transform .15s ease, background .18s ease, border-color .18s ease, color .18s ease;
}
.btn-primary{ background: var(--signal); color: #062824; border: 1px solid var(--signal); }
.btn-primary:hover{ transform: translateY(-2px); background: #6de5d3; }
.btn-ghost{ border: 1px solid var(--line); color: var(--text); }
.btn-ghost:hover{ border-color: var(--copper); color: var(--copper-bright); transform: translateY(-2px); }

/* ---------- portrait / chip module ---------- */
.chip-frame{
  position: relative;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 6px;
  padding: 18px;
  max-width: 320px;
  margin-left: auto;
}
.chip-frame::before, .chip-frame::after{
  content:"";
  position:absolute;
  width: 14px; height: 1px;
  background: var(--line);
  top: 30px;
}
.chip-frame::before{ left:-14px; }
.chip-frame::after{ right:-14px; }
.chip-photo{
  border-radius: 4px;
  border: 1px solid var(--line);
  filter: grayscale(.15) contrast(1.05);
  width: 100%;
}
.chip-caption{
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--text-faint);
  display:flex; justify-content: space-between;
  margin-top: 14px;
  border-top: 1px dashed var(--line);
  padding-top: 12px;
}
.chip-caption b{ color: var(--signal); font-weight: 600; }

/* ---------- stat strip ---------- */
.stat-strip{
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  margin-top: 64px;
}
.stat-strip div{
  padding: 20px 22px;
  border-left: 1px solid var(--line);
}
.stat-strip div:first-child{ border-left:none; }
.stat-num{ font-family: var(--mono); font-size: 26px; font-weight:700; color: var(--signal); }
.stat-label{ font-family: var(--mono); font-size: 11px; letter-spacing:.08em; text-transform:uppercase; color: var(--text-faint); margin-top:4px; }
@media (max-width: 900px){
  .stat-strip{ grid-template-columns: repeat(3,1fr); }
  .stat-strip div:nth-child(4){ border-left:none; }
}
@media (max-width: 700px){
  .stat-strip{ grid-template-columns: repeat(2,1fr); }
  .stat-strip div:nth-child(3){ border-left:none; }
  .stat-strip div:nth-child(4){ border-left:1px solid var(--line); }
}
@media (max-width: 480px){
  .stat-strip{ grid-template-columns: 1fr; }
  .stat-strip div{ border-left:none !important; border-top: 1px solid var(--line); }
  .stat-strip div:first-child{ border-top:none; }
}

/* ---------- card grid ---------- */
.grid{ display:grid; gap: 22px; }
.grid-2{ grid-template-columns: repeat(2, 1fr); }
.grid-3{ grid-template-columns: repeat(3, 1fr); }
@media (max-width: 900px){ .grid-2, .grid-3{ grid-template-columns: 1fr; } }

.card{
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 26px;
  transition: border-color .2s ease, transform .2s ease;
}
.card:hover{ border-color: var(--signal-dim); transform: translateY(-3px); }
.card-corner{ position:absolute; width:9px; height:9px; border: 1.4px solid var(--line); }
.card .card-corner:nth-of-type(1){ top:-1px; left:-1px; border-right:none; border-bottom:none; }
.card .card-corner:nth-of-type(2){ top:-1px; right:-1px; border-left:none; border-bottom:none; }

/* status LED */
.led{ width:7px; height:7px; border-radius:50%; background: var(--signal); box-shadow: 0 0 6px var(--signal); display:inline-block; }
.led.amber{ background: var(--amber); box-shadow: 0 0 6px var(--amber); }

/* project datasheet card */
.pcard{
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 28px 28px 24px;
  transition: border-color .2s ease, transform .2s ease;
}
.pcard:hover{ border-color: var(--copper); transform: translateY(-3px); }
.pcard-top{ display:flex; align-items:center; justify-content:space-between; margin-bottom: 14px; }
.pcard-id{ font-family: var(--mono); font-size: 11px; color: var(--text-faint); letter-spacing:.08em; }
.pcard-status{ display:flex; align-items:center; gap:7px; font-family: var(--mono); font-size: 10.5px; letter-spacing:.08em; text-transform:uppercase; color: var(--text-dim); }
.pcard h3{ margin-bottom: 6px; }
.pcard .date{ font-family: var(--mono); font-size:11.5px; color: var(--copper-bright); letter-spacing:.04em; margin-bottom:12px; display:block; }
.pcard p{ font-size: 14.5px; margin-bottom: 16px; }
.pins{ display:flex; flex-wrap:wrap; gap:8px; border-top: 1px dashed var(--line); padding-top: 14px; }
.pin{
  font-family: var(--mono); font-size: 11px; letter-spacing:.03em;
  color: var(--text-dim); background: var(--surface-2);
  border: 1px solid var(--line); border-radius: 3px;
  padding: 5px 9px;
}

/* ---------- timeline (education / internships) ---------- */
.tline{ position: relative; padding-left: 28px; }
.tline::before{
  content:"";
  position: absolute; left: 4px; top: 6px; bottom: 6px;
  width: 1px; background: var(--line);
}
.titem{ position: relative; padding-bottom: 30px; }
.titem:last-child{ padding-bottom: 0; }
.titem::before{
  content:"";
  position:absolute; left: -28px; top: 5px;
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--bg); border: 2px solid var(--signal);
}
.titem-meta{ font-family: var(--mono); font-size: 11.5px; color: var(--copper-bright); letter-spacing:.05em; margin-bottom: 4px; }
.titem h3{ margin-bottom: 4px; font-size: 15.5px; }
.titem p{ font-size: 14px; margin-bottom: 0; }

/* ---------- skills ---------- */
.skillrow{ display:flex; justify-content: space-between; align-items:baseline; padding: 14px 0; border-bottom: 1px solid var(--line-soft); }
.skillrow:last-child{ border-bottom:none; }
.skillrow .label{ font-family: var(--mono); font-size: 12px; letter-spacing:.08em; text-transform: uppercase; color: var(--text-faint); width: 120px; flex-shrink:0; }
.skilltags{ display:flex; flex-wrap:wrap; gap:8px; justify-content:flex-end; flex:1; }
.tag{ font-family: var(--mono); font-size: 12px; color: var(--text-dim); border: 1px solid var(--line); border-radius: 3px; padding: 5px 10px; }
@media (max-width: 700px){
  .skillrow{ flex-direction: column; align-items: flex-start; gap: 10px; }
  .skilltags{ justify-content: flex-start; }
}

/* ---------- certification cards ---------- */
.cert-card{ padding: 24px 24px 22px; }
.cert-top{ display:flex; align-items:center; justify-content:space-between; margin-bottom: 14px; }
.cert-issuer{ font-family: var(--mono); font-size: 10.5px; letter-spacing:.1em; text-transform:uppercase; color: var(--copper-bright); }
.cert-card h3{ text-transform:none; font-size: 16px; line-height:1.35; margin-bottom: 10px; }
.cert-meta{ font-family: var(--mono); font-size: 11.5px; color: var(--text-faint); border-top: 1px dashed var(--line); padding-top: 12px; display:flex; flex-wrap:wrap; gap: 6px 12px; }
.cert-meta b{ color: var(--signal); font-weight: 600; }

/* ---------- transmission form (contact) ---------- */
.form-card{ padding: 30px 30px 28px; }
.form-card h3{ margin-bottom: 6px; }
.form-card > p{ font-size: 14px; margin-bottom: 22px; }
.field{ margin-bottom: 18px; }
.field label{
  display:block; font-family: var(--mono); font-size: 11px; letter-spacing:.1em;
  text-transform: uppercase; color: var(--text-faint); margin-bottom: 8px;
}
.field input, .field textarea{
  width: 100%;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14.5px;
  padding: 12px 14px;
  transition: border-color .18s ease;
}
.field input::placeholder, .field textarea::placeholder{ color: var(--text-faint); }
.field input:focus, .field textarea:focus{
  outline: none; border-color: var(--signal);
}
.field textarea{ resize: vertical; min-height: 120px; font-family: var(--sans); }
.field-row{ display:grid; grid-template-columns: 1fr 1fr; gap: 18px; }
@media (max-width: 620px){ .field-row{ grid-template-columns: 1fr; } }
.form-status{ font-family: var(--mono); font-size: 12px; color: var(--signal); margin-top: 14px; min-height: 16px; }

/* ---------- badges (certifications / languages) ---------- */
.badgewrap{ display:flex; flex-wrap:wrap; gap:10px; }
.badge{
  font-family: var(--mono); font-size: 12px; letter-spacing:.03em;
  border: 1px solid var(--line); border-radius: 3px;
  padding: 9px 13px; color: var(--text-dim);
  display:flex; align-items:center; gap:8px;
}
.badge .led{ width:5px; height:5px; }

/* ---------- contact / pinout ---------- */
.pinout{ border: 1px solid var(--line); border-radius: 6px; overflow: hidden; }
.pinrow{
  display:grid; grid-template-columns: 90px 1fr auto;
  align-items:center; gap: 16px;
  padding: 22px 24px; border-bottom: 1px solid var(--line);
  transition: background .18s ease;
}
.pinrow:last-child{ border-bottom:none; }
.pinrow:hover{ background: var(--surface); }
.pinrow .pnum{ font-family: var(--mono); color: var(--text-faint); font-size: 12px; }
.pinrow .pname{ font-family: var(--mono); font-size: 12px; letter-spacing:.08em; text-transform:uppercase; color: var(--text-faint); }
.pinrow .pval{ font-size: 16px; color: var(--text); }
.pinrow .parrow{ font-family: var(--mono); color: var(--signal); opacity:0; transition: opacity .18s ease, transform .18s ease; }
.pinrow:hover .parrow{ opacity:1; transform: translateX(3px); }
@media (max-width: 620px){
  .pinrow{ grid-template-columns: 1fr; gap:4px; }
  .pinrow .parrow{ display:none; }
}

/* ---------- footer ---------- */
footer{ padding: 46px 0 60px; position: relative; z-index:1; }
.footer-inner{ display:flex; justify-content: space-between; align-items:center; flex-wrap:wrap; gap:16px; border-top: 1px solid var(--line); padding-top: 26px; }
.footer-inner p{ margin:0; font-family: var(--mono); font-size: 11.5px; color: var(--text-faint); letter-spacing:.03em; }
.footer-links{ display:flex; gap: 18px; }
.footer-links a{ font-family: var(--mono); font-size: 11.5px; color: var(--text-dim); letter-spacing:.04em; }
.footer-links a:hover{ color: var(--signal); }

/* ---------- page header (non-home pages) ---------- */
.pagehead{ padding: 64px 0 40px; }
.pagehead .lede{ margin-top: 14px; }

/* ---------- reveal on scroll ---------- */
.reveal{ opacity:0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in{ opacity:1; transform: translateY(0); }

/* ---------- publications ---------- */
.pub-card{
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 28px;
  transition: border-color .2s ease, transform .2s ease;
}
.pub-card:hover{ border-color: var(--signal-dim); transform: translateY(-2px); }
.pub-top{ display:flex; align-items:center; justify-content:space-between; gap:16px; flex-wrap:wrap; margin-bottom: 12px; }
.pub-date{ font-family: var(--mono); font-size: 11.5px; letter-spacing:.08em; color: var(--copper-bright); }
.pub-status{ display:flex; align-items:center; gap:7px; font-family: var(--mono); font-size: 10.5px; letter-spacing:.08em; text-transform:uppercase; color: var(--text-dim); }
.pub-card h3{ text-transform: none; font-size: 19px; line-height:1.3; margin-bottom: 10px; }
.pub-authors{ font-family: var(--mono); font-size: 12.5px; color: var(--text-dim); margin-bottom: 14px; }
.pub-authors b{ color: var(--text); font-weight:600; }
.pub-meta{ display:flex; flex-wrap:wrap; gap:8px; margin-bottom: 16px; }
.pub-link{
  font-family: var(--mono); font-size: 12px; letter-spacing:.05em; text-transform:uppercase;
  color: var(--signal); border: 1px solid var(--signal-dim); border-radius: 3px;
  padding: 8px 13px; display:inline-flex; align-items:center; gap:8px;
  transition: background .18s ease, color .18s ease;
}
.pub-link:hover{ background: var(--signal); color: #062824; }

.pub-stub-list{ border: 1px solid var(--line); border-radius: 6px; overflow: hidden; margin-top: 18px; }
.pub-stub{
  display:grid; grid-template-columns: 130px 1fr auto;
  align-items:center; gap: 16px;
  padding: 16px 22px; border-bottom: 1px solid var(--line);
  font-family: var(--mono);
}
.pub-stub:last-child{ border-bottom:none; }
.pub-stub .pdate{ font-size: 12px; color: var(--text-dim); }
.pub-stub .ptitle{ font-size: 12.5px; color: var(--text-faint); letter-spacing:.02em; text-transform:uppercase; }
.pub-stub .ppending{ font-size: 10.5px; color: var(--text-faint); border: 1px dashed var(--line); border-radius: 3px; padding: 4px 8px; letter-spacing:.06em; text-transform:uppercase; }
@media (max-width: 620px){
  .pub-stub{ grid-template-columns: 1fr; gap:6px; }
}

/* form (about/contact quick copy) */
.copyline{ display:flex; align-items:center; gap:10px; }
.copybtn{
  font-family: var(--mono); font-size: 11px; color: var(--text-faint);
  border: 1px solid var(--line); border-radius: 3px; padding: 4px 8px;
  cursor: pointer; background: transparent; transition: color .15s ease, border-color .15s ease;
}
.copybtn:hover{ color: var(--signal); border-color: var(--signal-dim); }