/* ============================================================
   simon.heilles.org — refined minimal editorial
   Instrument Serif (display) · Instrument Sans (body) · Spline Sans Mono (meta)
   ============================================================ */

@font-face {
  font-family: "Instrument Serif";
  src: url("fonts/InstrumentSerif-400.woff2") format("woff2");
  font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "Instrument Serif";
  src: url("fonts/InstrumentSerif-400-italic.woff2") format("woff2");
  font-weight: 400; font-style: italic; font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("fonts/InstrumentSans-400.woff2") format("woff2");
  font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("fonts/InstrumentSans-400-italic.woff2") format("woff2");
  font-weight: 400; font-style: italic; font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("fonts/InstrumentSans-500.woff2") format("woff2");
  font-weight: 500; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "Instrument Sans";
  src: url("fonts/InstrumentSans-600.woff2") format("woff2");
  font-weight: 600; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "Spline Sans Mono";
  src: url("fonts/SplineSansMono-400.woff2") format("woff2");
  font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "Spline Sans Mono";
  src: url("fonts/SplineSansMono-500.woff2") format("woff2");
  font-weight: 500; font-style: normal; font-display: swap;
}

/* ---------- tokens ---------- */

:root {
  --bg: #f5f1e8;
  --bg-raised: #efe9dd;
  --ink: #191510;
  --ink-soft: #6d6557;
  --hairline: rgba(25, 21, 16, 0.16);
  --hairline-strong: rgba(25, 21, 16, 0.4);
  --accent: #b0491c;
  --accent-ink: #ffffff;
  --grain-opacity: 0.05;

  --serif: "Instrument Serif", "Iowan Old Style", Georgia, serif;
  --sans: "Instrument Sans", "Avenir Next", "Segoe UI", sans-serif;
  --mono: "Spline Sans Mono", "SFMono-Regular", Menlo, monospace;

  --w: min(1120px, calc(100vw - clamp(2.5rem, 8vw, 8rem)));
}

:root[data-theme="dark"] {
  --bg: #14110c;
  --bg-raised: #1c1812;
  --ink: #ece5d8;
  --ink-soft: #97907f;
  --hairline: rgba(236, 229, 216, 0.16);
  --hairline-strong: rgba(236, 229, 216, 0.45);
  --accent: #e0693a;
  --accent-ink: #14110c;
  --grain-opacity: 0.07;
}

/* ---------- base ---------- */

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.35s ease, color 0.35s ease;
  overflow-x: hidden;
}

::selection { background: var(--accent); color: var(--accent-ink); }

a { color: inherit; }

em { font-family: var(--serif); font-style: italic; font-size: 1.06em; }

/* film-grain overlay */
.grain {
  position: fixed; inset: -50%;
  width: 200%; height: 200%;
  pointer-events: none;
  z-index: 999;
  opacity: var(--grain-opacity);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='240' height='240'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='240' height='240' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- top bar ---------- */

.topbar {
  position: fixed; top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex; align-items: center; gap: 2rem;
  width: 100%;
  padding: 1.1rem clamp(1.25rem, 4vw, 4rem);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--hairline);
}

.monogram {
  font-family: var(--serif);
  font-size: 1.35rem;
  text-decoration: none;
  letter-spacing: 0.02em;
}
.monogram-dot { color: var(--accent); }

.topnav {
  margin-left: auto;
  display: flex; gap: clamp(1rem, 3vw, 2.25rem);
}
.topnav a {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}
.topnav a:hover { color: var(--accent); }

/* theme toggle */
.theme-toggle {
  background: none; border: none; cursor: pointer; padding: 0.25rem;
}
.theme-toggle-track {
  display: block; width: 38px; height: 20px;
  border: 1px solid var(--hairline-strong);
  border-radius: 20px;
  position: relative;
  transition: border-color 0.2s ease;
}
.theme-toggle-thumb {
  position: absolute; top: 3px; left: 4px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--ink);
  transition: transform 0.3s cubic-bezier(0.5, 0, 0.2, 1.4), background-color 0.35s ease;
}
:root[data-theme="dark"] .theme-toggle-thumb { transform: translateX(17px); }
.theme-toggle:hover .theme-toggle-track { border-color: var(--accent); }

/* ---------- hero ---------- */

.hero {
  width: var(--w);
  margin: 0 auto;
  padding-top: clamp(8rem, 20vh, 13rem);
  padding-bottom: clamp(4rem, 10vh, 8rem);
  min-height: 92vh;
  display: flex; flex-direction: column; justify-content: flex-end;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: 1.5rem;
}

.hero-name {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(4rem, 14vw, 11.5rem);
  line-height: 0.92;
  letter-spacing: -0.015em;
  display: flex; flex-direction: column;
}
.hero-name .accent { color: var(--accent); }

.hero-lede {
  margin-top: 2.25rem;
  max-width: 34ch;
  font-size: clamp(1.2rem, 2.2vw, 1.6rem);
  line-height: 1.45;
  color: var(--ink-soft);
}
.hero-lede em { color: var(--ink); }

.hero-links {
  margin-top: 2.5rem;
  display: flex; flex-wrap: wrap; gap: 0.6rem 0;
}
.hero-links a {
  font-family: var(--mono);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-decoration: none;
  padding: 0.35rem 1rem;
  border: 1px solid var(--hairline);
  border-right: none;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.hero-links a:last-child { border-right: 1px solid var(--hairline); }
.hero-links a:hover { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }

.hero-rule {
  margin-top: clamp(3rem, 8vh, 5.5rem);
  padding-top: 1rem;
  border-top: 1px solid var(--hairline-strong);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.5rem 1.5rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--ink-soft);
}

/* ---------- sections ---------- */

.section {
  width: var(--w);
  margin: 0 auto;
  padding: clamp(3.5rem, 9vh, 6.5rem) 0;
  border-top: 1px solid var(--hairline);
  display: grid;
  grid-template-columns: minmax(140px, 1fr) minmax(0, 3.2fr);
  gap: 2rem clamp(2rem, 6vw, 6rem);
  /* scroll reveal */
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.section.visible { opacity: 1; transform: none; }

.section-label {
  display: flex; flex-direction: column; gap: 0.4rem;
  position: sticky; top: 5.5rem; align-self: start;
}
.section-num {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--accent);
  letter-spacing: 0.1em;
}
.section-title {
  font-family: var(--serif);
  font-size: clamp(1.7rem, 3vw, 2.3rem);
  line-height: 1.05;
}

/* now */
.lede {
  font-family: var(--serif);
  font-size: clamp(1.5rem, 2.8vw, 2.1rem);
  line-height: 1.35;
  max-width: 26em;
}
.lede em { color: var(--accent); font-size: 1em; }
.inline-link {
  text-decoration: none;
  border-bottom: 2px solid var(--accent);
  transition: color 0.2s ease;
}
.inline-link:hover { color: var(--accent); }

.body-copy {
  margin-top: 1.5rem;
  max-width: 58ch;
  color: var(--ink-soft);
}

.stats {
  margin-top: 2.75rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 1px solid var(--hairline);
  border-left: 1px solid var(--hairline);
}
.stat {
  padding: 1.25rem 1.25rem 1.1rem;
  border-right: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  display: flex; flex-direction: column; gap: 0.2rem;
}
.stat-num {
  font-family: var(--serif);
  font-size: clamp(1.9rem, 3.4vw, 2.6rem);
  line-height: 1;
}
.stat-label {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.tags {
  margin-top: 2rem;
  display: flex; flex-wrap: wrap; gap: 0.5rem;
}
.tags span {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  padding: 0.3rem 0.8rem;
  border: 1px solid var(--hairline);
  border-radius: 999px;
  color: var(--ink-soft);
}

/* work timeline */
.timeline { list-style: none; }
.timeline-item {
  display: grid;
  grid-template-columns: minmax(90px, 120px) 1fr;
  gap: 1.5rem;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--hairline);
  transition: transform 0.25s ease;
}
.timeline-item:first-child { padding-top: 0.25rem; }
.timeline-item:hover { transform: translateX(6px); }
.timeline-when {
  font-family: var(--mono);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  color: var(--accent);
  padding-top: 0.35rem;
}
.timeline-what h3 {
  font-family: var(--sans);
  font-weight: 600;
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
}
.timeline-what .org { font-weight: 400; color: var(--ink-soft); }
.timeline-what p { color: var(--ink-soft); max-width: 62ch; }

/* project cards */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 1px;
  background: var(--hairline);
  border: 1px solid var(--hairline);
}
.card {
  background: var(--bg);
  padding: 1.6rem 1.5rem 1.75rem;
  text-decoration: none;
  display: flex; flex-direction: column; gap: 0.75rem;
  transition: background-color 0.25s ease;
}
.card:hover { background: var(--bg-raised); }
.card-top { display: flex; justify-content: space-between; align-items: baseline; }
.card-kicker {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.card-arrow {
  color: var(--accent);
  font-size: 1.1rem;
  transition: transform 0.25s ease;
}
.card:hover .card-arrow { transform: translate(4px, -4px); }
.card h3 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: 1.7rem;
  line-height: 1.1;
}
.card p { color: var(--ink-soft); font-size: 0.95rem; }

/* research */
.pub {
  display: block;
  text-decoration: none;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--hairline);
}
.pub:first-child { padding-top: 0.25rem; }
.pub-kicker {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
}
.pub-title {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.3rem, 2.4vw, 1.75rem);
  line-height: 1.25;
  margin: 0.6rem 0 0.5rem;
  max-width: 30em;
  transition: color 0.2s ease;
}
.pub:hover .pub-title { color: var(--accent); }
.pub-meta { color: var(--ink-soft); font-size: 0.95rem; max-width: 60ch; }

/* education */
.edu { list-style: none; }
.edu li {
  display: grid;
  grid-template-columns: minmax(90px, 120px) 1fr;
  gap: 1.5rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--hairline);
}
.edu li:first-child { padding-top: 0.25rem; }
.edu-year {
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--accent);
  letter-spacing: 0.06em;
}
.edu-what { color: var(--ink-soft); }
.edu-what strong { font-weight: 600; color: var(--ink); }

.toolbox { margin-top: 2.25rem; }

/* ---------- footer ---------- */

.footer {
  margin-top: clamp(2rem, 6vh, 4rem);
  border-top: 1px solid var(--hairline-strong);
  padding: clamp(4rem, 10vh, 7rem) 0 2.5rem;
  width: var(--w);
  margin-left: auto; margin-right: auto;
  text-align: center;
}
.footer-big {
  font-family: var(--serif);
  font-size: clamp(2.4rem, 6vw, 4.5rem);
  line-height: 1.1;
  margin-bottom: 2rem;
}
.footer-big em { color: var(--accent); font-size: 1em; }
.cta {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.85rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  padding: 0.9rem 2.2rem;
  border: 1px solid var(--ink);
  border-radius: 999px;
  transition: background-color 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}
.cta:hover { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }

.footer-links {
  margin-top: 3rem;
  display: flex; justify-content: center; flex-wrap: wrap; gap: 1.75rem;
}
.footer-links a {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  color: var(--ink-soft);
  transition: color 0.2s ease;
}
.footer-links a:hover { color: var(--accent); }

.footer-small {
  margin-top: 2.5rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
}

/* ---------- load reveal ---------- */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  animation: rise 0.9s cubic-bezier(0.2, 0.6, 0.2, 1) forwards;
}
.d1 { animation-delay: 0.08s; }
.d2 { animation-delay: 0.18s; }
.d3 { animation-delay: 0.32s; }
.d4 { animation-delay: 0.44s; }
.d5 { animation-delay: 0.56s; }

@keyframes rise {
  to { opacity: 1; transform: none; }
}

/* ---------- responsive ---------- */

@media (max-width: 760px) {
  .topnav { display: none; }
  .theme-toggle { margin-left: auto; }

  .hero { min-height: 78vh; }
  .hero-name { font-size: clamp(3.4rem, 17vw, 5.5rem); }

  .section {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  .section-label {
    position: static;
    flex-direction: row; align-items: baseline; gap: 0.9rem;
  }

  .stats { grid-template-columns: 1fr; border-left: 1px solid var(--hairline); }
  .timeline-item, .edu li { grid-template-columns: 1fr; gap: 0.35rem; }
}

/* ---------- reduced motion ---------- */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { animation: none; opacity: 1; transform: none; }
  .section { opacity: 1; transform: none; transition: none; }
  * { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}