/* ============================================================
   AetherNeural — ethereal + scholarly research lab
   Deep indigo / violet / near-black · hairline graphics ·
   serif display + clean sans · inline SVG/CSS art only
   ============================================================ */

:root {
  --bg: #060611;
  --bg-2: #0b0b1c;
  --bg-3: #101028;
  --surface: rgba(22, 20, 44, 0.42);
  --surface-solid: #12122a;
  --ink: #ece9f8;
  --muted: #a5a0c2;
  --faint: #6e6890;
  --line: rgba(158, 148, 235, 0.16);
  --line-strong: rgba(158, 148, 235, 0.32);
  --accent: #9d8cff;
  --accent-soft: rgba(157, 140, 255, 0.12);
  --mint: #7fe3d2;
  --mint-soft: rgba(127, 227, 210, 0.10);
  --gold: #d9c193;
  --serif: "Fraunces", "Iowan Old Style", Georgia, serif;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", "SFMono-Regular", Menlo, monospace;
  --radius: 14px;
  --max: 1120px;
  --max-wide: 1320px;
  --ease: cubic-bezier(0.22, 0.61, 0.21, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Ambient starfield / aurora washes behind everything */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(900px 520px at 12% -6%, rgba(109, 88, 246, 0.14), transparent 60%),
    radial-gradient(760px 480px at 88% 8%, rgba(127, 227, 210, 0.07), transparent 60%),
    radial-gradient(1100px 700px at 50% 115%, rgba(74, 56, 190, 0.12), transparent 62%),
    var(--bg);
}

::selection { background: rgba(157, 140, 255, 0.35); color: #fff; }

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

a { color: var(--accent); text-decoration: none; }
a:hover { color: #c3b6ff; }

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 480;
  line-height: 1.16;
  letter-spacing: -0.015em;
  margin: 0 0 0.6em;
  color: var(--ink);
}

p { margin: 0 0 1.15em; }

.container { max-width: var(--max); margin: 0 auto; padding: 0 clamp(1.25rem, 4vw, 2.5rem); }
.container--wide { max-width: var(--max-wide); }

/* ---------- Eyebrows / labels ---------- */
.eyebrow {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 1.1rem;
  display: flex;
  align-items: center;
  gap: 0.9rem;
}
.eyebrow::before {
  content: "";
  width: 2.4rem;
  height: 1px;
  background: linear-gradient(90deg, var(--accent), transparent);
}
.eyebrow--center { justify-content: center; }
.eyebrow--center::after {
  content: "";
  width: 2.4rem;
  height: 1px;
  background: linear-gradient(270deg, var(--accent), transparent);
}

/* ---------- Header / nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(6, 6, 17, 0.72);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 0 clamp(1.25rem, 4vw, 2.5rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.4rem;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.28rem;
  letter-spacing: 0.01em;
}
.brand:hover { color: var(--ink); }
.brand-mark { width: 30px; height: 30px; flex: none; }

.nav-links { display: flex; align-items: center; gap: 0.25rem; list-style: none; margin: 0; padding: 0; }
.nav-links a {
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 500;
  padding: 0.55rem 0.85rem;
  border-radius: 8px;
  position: relative;
  transition: color 0.25s var(--ease);
}
.nav-links a:hover { color: var(--ink); }
.nav-links a[aria-current="page"] { color: var(--ink); }
.nav-links a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 0.85rem;
  right: 0.85rem;
  bottom: 0.28rem;
  height: 1px;
  background: var(--accent);
}
.nav-cta a {
  border: 1px solid var(--line-strong);
  color: var(--ink);
  padding: 0.5rem 1.1rem;
  border-radius: 999px;
  margin-left: 0.6rem;
  transition: border-color 0.25s, background 0.25s;
}
.nav-cta a:hover, .nav-cta a[aria-current="page"] { border-color: var(--accent); background: var(--accent-soft); color: var(--ink); }
.nav-cta a[aria-current="page"]::after { display: none; }

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  color: var(--ink);
  width: 2.7rem;
  height: 2.7rem;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(5rem, 12vh, 8.5rem) 0 clamp(4rem, 9vh, 6.5rem);
  border-bottom: 1px solid var(--line);
}
#constellation {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.9;
}
.hero-inner { position: relative; z-index: 1; max-width: 62rem; }
.hero h1 {
  font-size: clamp(3rem, 8vw, 5.6rem);
  font-weight: 430;
  margin-bottom: 0.35em;
}
.hero h1 em {
  font-style: italic;
  background: linear-gradient(100deg, #cfc2ff 10%, var(--accent) 45%, var(--mint) 90%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-lede {
  font-family: var(--serif);
  font-size: clamp(1.25rem, 2.6vw, 1.6rem);
  line-height: 1.55;
  color: var(--muted);
  max-width: 44rem;
  font-weight: 400;
}
.hero-lede strong { color: var(--ink); font-weight: 500; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: 2.2rem; }
.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.6rem;
  margin-top: 3.2rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--line);
  font-size: 0.85rem;
  color: var(--faint);
}
.hero-meta span b { color: var(--muted); font-weight: 600; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.85rem 1.7rem;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.25s var(--ease), box-shadow 0.25s, background 0.25s, border-color 0.25s;
}
.btn-primary {
  background: linear-gradient(120deg, #7c63f5, #9d8cff);
  color: #0d0b22;
  box-shadow: 0 8px 30px rgba(124, 99, 245, 0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 38px rgba(124, 99, 245, 0.45); color: #0d0b22; }
.btn-ghost {
  border-color: var(--line-strong);
  color: var(--ink);
  background: rgba(20, 18, 44, 0.35);
}
.btn-ghost:hover { border-color: var(--accent); background: var(--accent-soft); color: var(--ink); }

/* ---------- Sections ---------- */
.section { padding: clamp(4rem, 9vh, 6.5rem) 0; position: relative; }
.section + .section { border-top: 1px solid var(--line); }
.section-head { max-width: 46rem; margin-bottom: 3rem; }
.section-head h2 { font-size: clamp(1.9rem, 4vw, 2.7rem); margin-bottom: 0.4em; }
.section-head p { color: var(--muted); font-size: 1.08rem; margin: 0; }
.section-foot { margin-top: 2.6rem; }

/* ---------- Cards / grids ---------- */
.grid { display: grid; gap: 1.4rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  padding: 1.9rem 1.7rem;
  transition: transform 0.3s var(--ease), border-color 0.3s, box-shadow 0.3s;
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line-strong), transparent);
  opacity: 0.8;
}
.card:hover {
  transform: translateY(-4px);
  border-color: var(--line-strong);
  box-shadow: 0 18px 44px rgba(5, 4, 18, 0.55), 0 0 0 1px rgba(157, 140, 255, 0.06);
}
.card-index {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--faint);
  margin-bottom: 1rem;
  display: block;
}
.card h3 { font-size: 1.32rem; margin-bottom: 0.55em; }
.card h3 a { color: var(--ink); }
.card h3 a:hover { color: var(--accent); }
.card p { color: var(--muted); font-size: 0.98rem; margin-bottom: 1rem; }
.card .card-link {
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-top: 0.4rem;
}
.card-icon { width: 44px; height: 44px; margin-bottom: 1.2rem; }

/* Status pills */
.status {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  padding: 0.32rem 0.85rem;
  border-radius: 999px;
  border: 1px solid;
  margin-bottom: 1.1rem;
}
.status::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: currentColor; }
.status-active { color: var(--mint); border-color: rgba(127, 227, 210, 0.4); background: var(--mint-soft); }
.status-active::before { animation: pulse 2.4s ease-in-out infinite; }
.status-exploratory { color: var(--gold); border-color: rgba(217, 193, 147, 0.4); background: rgba(217, 193, 147, 0.08); }
.status-archived { color: var(--faint); border-color: var(--line-strong); background: rgba(110, 104, 144, 0.08); }

@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.35; } }

/* Tech tags */
.tags { display: flex; flex-wrap: wrap; gap: 0.5rem; margin: 1.1rem 0 0; padding: 0; list-style: none; }
.tags li {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.28rem 0.65rem;
  background: rgba(10, 10, 26, 0.5);
}

/* ---------- Research deep-dive ---------- */
.research-area {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  padding: clamp(1.8rem, 4vw, 3rem);
  margin-bottom: 2rem;
  position: relative;
  overflow: hidden;
}
.research-area::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--accent), var(--mint));
  opacity: 0.55;
}
.research-area h2 { font-size: clamp(1.6rem, 3.4vw, 2.2rem); }
.research-area .q-list { list-style: none; margin: 1.4rem 0 0; padding: 0; }
.research-area .q-list li {
  padding: 0.9rem 0 0.9rem 1.6rem;
  border-top: 1px dashed var(--line);
  color: var(--muted);
  position: relative;
  font-size: 1rem;
}
.research-area .q-list li::before {
  content: "◇";
  position: absolute;
  left: 0.25rem;
  color: var(--accent);
  font-size: 0.8rem;
  top: 1.15rem;
}
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 2.4rem; margin-top: 1.8rem; }
.two-col h4 {
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.9rem;
}
.two-col p, .two-col li { color: var(--muted); font-size: 0.98rem; }
.two-col ul { margin: 0; padding-left: 1.1rem; }
.two-col li { margin-bottom: 0.6rem; }

/* ---------- Notes ---------- */
.note-card .note-date {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  color: var(--faint);
  text-transform: uppercase;
  display: block;
  margin-bottom: 0.9rem;
}
.note-card h3 { font-size: 1.45rem; }
.note-body { max-width: 46rem; }
.note-body p { color: #c9c4e2; }
.note-body h3 { margin-top: 2.2rem; font-size: 1.4rem; }
.note-body blockquote {
  margin: 1.8rem 0;
  padding: 1.2rem 1.6rem;
  border-left: 2px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 10px 10px 0;
  font-family: var(--serif);
  font-style: italic;
  font-size: 1.15rem;
  color: var(--ink);
}
.note-rule { border: none; border-top: 1px solid var(--line); margin: 2.6rem 0; }
.note-nav { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3rem; padding-top: 1.6rem; border-top: 1px solid var(--line); }
.note-nav a { font-size: 0.92rem; font-weight: 600; }

/* ---------- Page hero (inner pages) ---------- */
.page-hero {
  padding: clamp(3.6rem, 8vh, 5.5rem) 0 clamp(2.6rem, 6vh, 4rem);
  border-bottom: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}
.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(700px 340px at 20% 0%, rgba(109, 88, 246, 0.16), transparent 65%);
  pointer-events: none;
}
.page-hero h1 { font-size: clamp(2.4rem, 5.5vw, 3.8rem); position: relative; }
.page-hero .lede { color: var(--muted); font-size: 1.15rem; max-width: 46rem; position: relative; margin-bottom: 0; }

/* ---------- About ---------- */
.principle { border-left: 1px solid var(--line-strong); padding: 0.4rem 0 0.4rem 1.6rem; margin-bottom: 2rem; }
.principle h3 { font-size: 1.25rem; margin-bottom: 0.4em; }
.principle p { color: var(--muted); margin: 0; font-size: 0.99rem; }

/* ---------- Contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1.25fr; gap: 2.5rem; align-items: start; }
.contact-details { list-style: none; margin: 1.6rem 0 0; padding: 0; }
.contact-details li { padding: 1rem 0; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.98rem; }
.contact-details li b { display: block; color: var(--ink); font-weight: 600; font-size: 0.8rem; letter-spacing: 0.18em; text-transform: uppercase; margin-bottom: 0.35rem; }
.form-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  padding: clamp(1.6rem, 3.5vw, 2.6rem);
}
.field { margin-bottom: 1.3rem; }
.field label { display: block; font-size: 0.82rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: 0.5rem; }
.field input, .field select, .field textarea {
  width: 100%;
  background: rgba(8, 8, 20, 0.65);
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1rem;
  padding: 0.8rem 1rem;
  transition: border-color 0.25s, box-shadow 0.25s;
}
.field textarea { min-height: 9rem; resize: vertical; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(157, 140, 255, 0.18);
}
.form-note { font-size: 0.85rem; color: var(--faint); margin-top: 1rem; }
.form-success {
  display: none;
  border: 1px solid rgba(127, 227, 210, 0.4);
  background: var(--mint-soft);
  border-radius: var(--radius);
  padding: 2.2rem;
  text-align: center;
}
.form-success.show { display: block; }
.form-success h3 { font-size: 1.5rem; margin-bottom: 0.5em; }
.form-success p { color: var(--muted); margin: 0; }

/* ---------- CTA band ---------- */
.cta-band {
  border: 1px solid var(--line);
  border-radius: calc(var(--radius) + 6px);
  background:
    radial-gradient(600px 300px at 50% 120%, rgba(124, 99, 245, 0.22), transparent 70%),
    var(--surface);
  padding: clamp(2.6rem, 6vw, 4.5rem) clamp(1.8rem, 5vw, 4rem);
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-band h2 { font-size: clamp(1.8rem, 4vw, 2.6rem); margin-bottom: 0.5em; }
.cta-band p { color: var(--muted); max-width: 38rem; margin: 0 auto 1.8rem; }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); padding: 3.4rem 0 2rem; margin-top: 2rem; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 2.4rem; margin-bottom: 2.6rem; }
.footer-grid h4 {
  font-family: var(--sans);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--faint);
  margin-bottom: 1rem;
}
.footer-grid ul { list-style: none; margin: 0; padding: 0; }
.footer-grid li { margin-bottom: 0.55rem; }
.footer-grid a { color: var(--muted); font-size: 0.94rem; }
.footer-grid a:hover { color: var(--ink); }
.footer-brand p { color: var(--faint); font-size: 0.92rem; max-width: 22rem; }
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--line);
  font-size: 0.82rem;
  color: var(--faint);
}
.footer-bottom p { margin: 0; }

/* ---------- Hairline divider motif ---------- */
.hairline { display: flex; align-items: center; gap: 1rem; margin: 0 0 2.4rem; color: var(--faint); }
.hairline::before, .hairline::after { content: ""; flex: 1; height: 1px; background: var(--line); }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity 0.8s var(--ease), transform 0.8s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: 0.1s; }
.reveal[data-delay="2"] { transition-delay: 0.2s; }
.reveal[data-delay="3"] { transition-delay: 0.3s; }

/* ---------- Skip link / a11y ---------- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #0d0b22;
  padding: 0.7rem 1.2rem;
  border-radius: 0 0 10px 0;
  font-weight: 700;
  z-index: 100;
}
.skip-link:focus { left: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .two-col { grid-template-columns: 1fr; gap: 1.6rem; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  body { font-size: 1rem; }
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute;
    top: 4.4rem;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    background: rgba(8, 8, 20, 0.98);
    border-bottom: 1px solid var(--line);
    padding: 0.8rem 1.25rem 1.4rem;
    gap: 0.2rem;
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 0.8rem 0.6rem; font-size: 1.02rem; }
  .nav-cta a { margin: 0.4rem 0 0; text-align: center; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .note-nav { flex-direction: column; }
}

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}