/* ============================================================
   Zaid Mahboob — homepage
   Dark navy / sky-blue technical design. No build step, no CDN.
   (The blog uses css/styles.css + css/blog.css — untouched.)
   ============================================================ */

:root {
  /* surfaces */
  --bg:        #051424;
  --surface:   #051424;
  --surf-dim:  #041020;
  --s-lowest:  #010f1f;
  --s-low:     #0d1c2d;
  --s-cont:    #122131;
  --s-high:    #1c2b3c;
  --s-highest: #273647;
  --s-variant: #273647;
  --s-bright:  #2c3a4c;

  /* lines */
  --outline:      #909097;
  --outline-var:  #45464d;

  /* text */
  --ink:        #d4e4fa;   /* on-surface */
  --ink-var:    #c6c6cd;   /* muted */
  --primary:    #bec6e0;   /* headings + brand (lavender-grey) */
  --on-primary: #283044;
  --prim-cont:  #0f172a;
  --on-prim-cont:#aab3cd;

  /* accents */
  --secondary:   #7bd0ff;  /* sky blue */
  --on-secondary:#00354a;
  --sec-cont:    #00a6e0;
  --tertiary:    #ffb95f;  /* amber — outreach */
  --on-tertiary: #472a00;
  --gold:        #ffcf6f;
  --silver:      #c9d3de;

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

  --maxw:  1440px;
  --pad:   32px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
::selection { background: var(--secondary); color: var(--on-secondary); }

::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--outline-var); border-radius: 4px; }

.material-symbols-outlined {
  font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
  line-height: 1;
  user-select: none;
}

/* dotted engineering grid, used as a subtle overlay */
.code-grid {
  background-image: radial-gradient(circle, var(--outline-var) 1px, transparent 1px);
  background-size: 20px 20px;
}

/* ---------- shells ---------- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 var(--pad); }
.section { padding: 72px 0; border-bottom: 1px solid var(--outline-var); }

/* ---------- section header ---------- */
.sec-head { display: flex; align-items: flex-end; gap: 24px; margin-bottom: 44px; }
.sec-head__l { min-width: 0; }
.eyebrow {
  display: block; font-family: var(--mono); font-size: 12px; font-weight: 500;
  letter-spacing: .18em; text-transform: uppercase; color: var(--secondary);
  margin-bottom: 12px;
}
.sec-title {
  font-size: clamp(24px, 4vw, 32px); font-weight: 700; line-height: 1.15;
  letter-spacing: -.01em; text-transform: uppercase; color: var(--primary);
}
.sec-rule { flex: 1; height: 1px; background: var(--outline-var); margin-bottom: 8px; }

/* ---------- nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50; height: 64px;
  background: rgba(5,20,36,.82); backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--outline-var);
}
.nav__inner { max-width: var(--maxw); margin: 0 auto; padding: 0 var(--pad);
  height: 100%; display: flex; align-items: center; justify-content: space-between; }
.nav__brand { font-size: 20px; font-weight: 800; letter-spacing: -.02em; color: var(--primary); }
.nav__links { display: flex; gap: 26px; align-items: center; }
.nav__links a {
  font-size: 14px; font-weight: 600; color: var(--ink-var);
  transition: color .2s; white-space: nowrap;
}
.nav__links a:hover { color: var(--secondary); }
.nav__links a.is-active { color: var(--secondary); }
.nav__cta {
  background: var(--primary); color: var(--on-primary);
  font-size: 14px; font-weight: 600; padding: 9px 22px;
  transition: transform .1s, background .2s;
}
.nav__cta:hover { background: #d3daf0; }
.nav__cta:active { transform: scale(.96); }
@media (max-width: 900px) { .nav__links { display: none; } }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 12px; justify-content: center;
  font-size: 14px; font-weight: 600; letter-spacing: .03em; text-transform: uppercase;
  padding: 15px 34px; transition: background .2s, border-color .2s, color .2s;
  cursor: pointer;
}
.btn--primary { background: var(--secondary); color: var(--on-secondary); border: 1px solid var(--secondary); }
.btn--primary:hover { background: var(--sec-cont); border-color: var(--sec-cont); }
.btn--ghost { border: 1px solid var(--outline); color: var(--primary); background: transparent; }
.btn--ghost:hover { background: var(--s-variant); }
.btn--tertiary { background: var(--tertiary); color: var(--on-tertiary); border: 1px solid var(--tertiary); }
.btn--tertiary:hover { filter: brightness(1.08); }
.btn .material-symbols-outlined { font-size: 20px; }

/* ---------- chips ---------- */
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  font-family: var(--mono); font-size: 11px; letter-spacing: .02em;
  color: var(--ink-var); background: var(--s-cont);
  border: 1px solid var(--outline-var); padding: 6px 12px;
}

/* ============================================================
   HERO
   ============================================================ */
.hero { padding: 60px 0 72px; border-bottom: 1px solid var(--outline-var); }
.hero__grid {
  display: grid; grid-template-columns: 1.4fr 1fr; gap: 56px; align-items: center;
  min-height: 72vh;
}
.hero__status {
  display: inline-flex; align-items: center; gap: 12px;
  font-family: var(--mono); font-size: 12px; letter-spacing: .12em; text-transform: uppercase;
  color: var(--secondary); margin-bottom: 28px;
}
.hero__dot { width: 8px; height: 8px; border-radius: 50%; background: var(--secondary);
  box-shadow: 0 0 10px var(--secondary); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: .35; } }
.hero__name {
  font-size: clamp(52px, 9vw, 104px); font-weight: 800; line-height: .92;
  letter-spacing: -.03em; text-transform: uppercase; color: var(--primary);
  margin-bottom: 30px;
}
.hero__tag {
  font-size: clamp(16px, 1.5vw, 18px); line-height: 1.6; color: var(--ink-var);
  max-width: 40ch; border-left: 4px solid var(--secondary); padding-left: 22px;
  margin-bottom: 30px;
}
.hero__tag strong { color: var(--ink); font-weight: 600; }
.hero__chips { margin-bottom: 40px; }
.hero__cta { display: flex; flex-wrap: wrap; gap: 16px; }

.portrait {
  position: relative; aspect-ratio: 4 / 5; width: 100%;
  background: var(--s-lowest); border: 1px solid var(--outline-var); overflow: hidden;
}
.portrait img { width: 100%; height: 100%; object-fit: cover; }
.portrait__grid { position: absolute; inset: 0; opacity: .18; pointer-events: none; }
.portrait__hud {
  position: absolute; left: 0; right: 0; bottom: 0;
  background: rgba(18,33,49,.92); backdrop-filter: blur(6px);
  border-top: 1px solid var(--outline-var); padding: 18px 20px;
}
.portrait__hud .k { display: block; font-family: var(--mono); font-size: 10px;
  letter-spacing: .1em; text-transform: uppercase; color: var(--secondary); margin-bottom: 4px; }
.portrait__hud .v { display: block; font-size: 13px; color: var(--primary);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

@media (max-width: 860px) {
  .hero__grid { grid-template-columns: 1fr; gap: 40px; }
  .hero__portrait { max-width: 420px; }
}

/* ============================================================
   NOW  (current work — brief, no v‖L‖ω definition)
   ============================================================ */
.split { display: grid; grid-template-columns: 1.15fr .85fr; gap: 48px; align-items: center; }
.split--rev .split__media { order: -1; }
.prose p { color: var(--ink-var); font-size: 17px; line-height: 1.7; margin-bottom: 18px; }
.prose p:last-child { margin-bottom: 0; }
.prose strong { color: var(--ink); font-weight: 600; }
/* framed media: a controlled landscape crop, never a full-height tower */
figure.media { border: 1px solid var(--outline-var); background: var(--s-lowest); overflow: hidden; }
figure.media img {
  display: block; width: 100%;
  height: clamp(300px, 34vw, 440px);
  object-fit: cover; object-position: 50% 18%;
}
figure.media figcaption {
  font-family: var(--mono); font-size: 12px; color: var(--ink-var);
  padding: 12px 16px; border-top: 1px solid var(--outline-var); background: var(--s-cont);
}
@media (max-width: 820px) {
  .split { grid-template-columns: 1fr; gap: 28px; align-items: start; }
  .split--rev .split__media { order: 0; }
  figure.media img { height: clamp(240px, 56vw, 360px); }
}

/* ============================================================
   JOURNEY  (text + stat cards)
   ============================================================ */
.stats { display: grid; gap: 12px; }
.stat { background: var(--s-high); border-left: 4px solid var(--secondary); padding: 20px 22px; }
.stat--gold   { border-left-color: var(--gold); }
.stat--silver { border-left-color: var(--silver); }
.stat__k { display: block; font-size: 30px; font-weight: 800; color: var(--primary); letter-spacing: -.01em; }
.stat__v { display: block; font-size: 13px; color: var(--ink-var); margin-top: 4px; }
.stat__v sup { font-size: .7em; }

/* ============================================================
   EXPERIENCE  (card grid)
   ============================================================ */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card {
  background: var(--s-cont); border: 1px solid var(--outline-var);
  padding: 28px; transition: border-color .2s, background .2s;
}
.card:hover { border-color: var(--secondary); }
.card__top { display: flex; justify-content: space-between; align-items: flex-start; gap: 12px; margin-bottom: 16px; }
.badge {
  font-family: var(--mono); font-size: 10px; font-weight: 600; letter-spacing: .08em;
  text-transform: uppercase; padding: 4px 8px;
}
.badge--now { background: rgba(123,208,255,.12); color: var(--secondary); }
.badge--past { background: var(--s-variant); color: var(--ink-var); }
.card__when { font-family: var(--mono); font-size: 12px; color: var(--ink-var); }
.card__org { font-size: 20px; font-weight: 700; color: var(--primary); }
.card__role { font-size: 14px; font-weight: 600; color: var(--secondary); margin: 4px 0 14px; }
.card__desc { font-size: 14px; color: var(--ink-var); line-height: 1.6; }
.card__desc + .card__desc { margin-top: 12px; }
.card__desc strong { color: var(--ink); font-weight: 600; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 20px; }
.tags span { font-size: 11px; font-weight: 500; color: var(--ink-var); background: var(--s-variant); padding: 4px 9px; }

/* projects */
.proj__title { font-size: 20px; font-weight: 700; color: var(--primary); margin-bottom: 12px; }
.proj__desc { font-size: 14px; color: var(--ink-var); line-height: 1.6; margin-bottom: 24px; }
.proj__hash { font-family: var(--mono); font-size: 11px; letter-spacing: .02em; text-transform: uppercase; color: var(--secondary); }

@media (max-width: 820px) { .grid-2, .grid-3 { grid-template-columns: 1fr; } }

/* ============================================================
   LAB  (spec sheet)
   ============================================================ */
.spec { background: var(--s-lowest); border: 1px solid var(--outline-var); }
.spec__head {
  background: var(--s-variant); padding: 14px 20px;
  font-size: 14px; font-weight: 600; letter-spacing: .04em; text-transform: uppercase; color: var(--primary);
  border-bottom: 1px solid var(--outline-var);
}
.spec__row {
  display: grid; grid-template-columns: 240px 1fr; gap: 16px; padding: 16px 20px;
  border-bottom: 1px solid rgba(69,70,77,.4); transition: background .2s;
}
.spec__row:last-child { border-bottom: none; }
.spec__row:hover { background: var(--s-variant); }
.spec__k { font-weight: 700; color: var(--secondary); font-size: 14px; }
.spec__v { color: var(--ink); font-size: 15px; }
@media (max-width: 620px) { .spec__row { grid-template-columns: 1fr; gap: 4px; } }

/* ============================================================
   RESEARCH
   ============================================================ */
.metrics { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin-bottom: 32px; }
.metric { background: var(--s-high); border-left: 4px solid var(--secondary); padding: 22px; }
.metric__k { font-size: 34px; font-weight: 800; color: var(--primary); line-height: 1; }
.metric__v { font-size: 12px; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-var); margin-top: 8px; }
.metric--link { display: flex; align-items: center; background: var(--secondary); border: none; transition: background .2s; }
.metric--link:hover { background: var(--sec-cont); }
.metric--link .metric__v { color: var(--on-secondary); font-weight: 700; margin: 0; }
@media (max-width: 720px) { .metrics { grid-template-columns: 1fr 1fr; } }

.pubs { display: flex; flex-direction: column; gap: 12px; margin-bottom: 44px; }
.pub {
  display: grid; grid-template-columns: 70px 1fr auto; gap: 20px; align-items: center;
  background: var(--s-cont); border: 1px solid var(--outline-var); padding: 20px 24px;
  transition: background .2s, border-color .2s;
}
.pub:hover { background: var(--s-variant); border-color: var(--outline); }
.pub__year { font-family: var(--mono); font-size: 14px; color: var(--secondary); font-weight: 500; }
.pub__title { font-size: 16px; font-weight: 600; color: var(--primary); line-height: 1.35; }
.pub__venue { font-size: 13px; color: var(--ink-var); margin-top: 4px; }
.pub__doi { font-family: var(--mono); font-size: 12px; color: var(--secondary); white-space: nowrap; }
.pub__doi:hover { text-decoration: underline; }
@media (max-width: 640px) {
  .pub { grid-template-columns: 1fr; gap: 8px; }
  .pub__doi { justify-self: start; }
}

.skills h3 { font-size: 14px; font-weight: 600; letter-spacing: .14em; text-transform: uppercase;
  color: var(--ink-var); margin-bottom: 20px; }
.skills__grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px; }
.skillcat__k { display: block; font-family: var(--mono); font-size: 11px; letter-spacing: .1em;
  text-transform: uppercase; color: var(--secondary); margin-bottom: 10px; }
.skillcat__items { display: flex; flex-wrap: wrap; gap: 7px; }
.skillcat__items span { font-size: 12px; color: var(--ink-var); background: var(--s-cont);
  border: 1px solid var(--outline-var); padding: 4px 9px; }

/* ============================================================
   AI FOR KIDS band
   ============================================================ */
.kids { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.kids__eyebrow { color: var(--tertiary); }
.kids__title { font-size: clamp(22px, 3vw, 30px); font-weight: 700; color: var(--primary); margin-bottom: 20px; }
.kids__lede { font-size: 17px; color: var(--ink-var); line-height: 1.6; margin-bottom: 30px; }
.kids__cards { display: grid; gap: 16px; }
.feat { display: flex; align-items: center; gap: 22px; background: var(--s-cont);
  border: 1px solid var(--outline-var); padding: 22px 24px; }
.feat .material-symbols-outlined { font-size: 44px; color: var(--tertiary); flex-shrink: 0; }
.feat__t { font-size: 18px; font-weight: 700; color: var(--primary); }
.feat__d { font-size: 14px; color: var(--ink-var); margin-top: 3px; }
@media (max-width: 820px) { .kids { grid-template-columns: 1fr; gap: 32px; } }

/* ============================================================
   WRITING / BLOG
   ============================================================ */
.writing__lede { font-size: 17px; color: var(--ink-var); line-height: 1.6; max-width: 68ch; margin-bottom: 32px; }
.writing__lede a { color: var(--secondary); }
.wgrid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.wcard { background: var(--s-cont); border: 1px solid var(--outline-var); padding: 26px;
  display: flex; flex-direction: column; transition: border-color .2s, background .2s; }
.wcard:hover { border-color: var(--secondary); background: var(--s-variant); }
.wcard__tag { font-family: var(--mono); font-size: 11px; letter-spacing: .04em; color: var(--ink-var); margin-bottom: 14px; }
.wcard--feat .wcard__tag { color: var(--secondary); }
.wcard__title { font-size: 18px; font-weight: 700; color: var(--primary); line-height: 1.25; margin-bottom: 10px; }
.wcard__desc { font-size: 14px; color: var(--ink-var); line-height: 1.6; flex: 1; }
.wcard__go { font-family: var(--mono); font-size: 12px; color: var(--secondary); margin-top: 18px; }
@media (max-width: 900px) { .wgrid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .wgrid { grid-template-columns: 1fr; } }

/* ============================================================
   CONTACT
   ============================================================ */
.contact-band { position: relative; background: var(--prim-cont);
  border: 1px solid var(--outline); padding: 64px 40px; overflow: hidden; }
.contact-band__grid { position: absolute; inset: 0; opacity: .1; }
.contact-band__inner { position: relative; z-index: 1; text-align: center; }
.contact-band__title { font-size: clamp(28px, 4vw, 40px); font-weight: 800; text-transform: uppercase;
  letter-spacing: -.01em; color: var(--primary); margin-bottom: 18px; }
.contact-band__lede { font-size: 18px; color: var(--on-prim-cont); line-height: 1.6;
  max-width: 60ch; margin: 0 auto 36px; }
.contact-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 14px; }
.clink { display: flex; flex-direction: column; align-items: flex-start; gap: 4px;
  background: var(--s-lowest); border: 1px solid var(--outline-var); padding: 16px 22px;
  min-width: 200px; text-align: left; transition: border-color .2s; }
.clink:hover { border-color: var(--secondary); }
.clink__k { font-family: var(--mono); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; color: var(--secondary); }
.clink__v { font-size: 15px; color: var(--ink); }
@media (max-width: 560px) { .contact-band { padding: 44px 22px; } .clink { min-width: 0; width: 100%; } }

/* ---------- footer ---------- */
.footer { background: var(--surf-dim); border-top: 1px solid var(--outline-var); }
.footer__inner { max-width: var(--maxw); margin: 0 auto; padding: 40px var(--pad);
  display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px; }
.footer__brand { font-weight: 800; letter-spacing: -.02em; color: var(--primary); }
.footer__meta { font-family: var(--mono); font-size: 11px; letter-spacing: .06em;
  text-transform: uppercase; color: var(--ink-var); }
.footer__links { display: flex; gap: 22px; }
.footer__links a { font-family: var(--mono); font-size: 11px; text-transform: uppercase;
  letter-spacing: .06em; color: var(--ink-var); transition: color .2s; }
.footer__links a:hover { color: var(--secondary); }

/* ---------- reveal ---------- */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; scroll-behavior: auto !important; }
  .reveal { opacity: 1; transform: none; transition: none; }
}