:root {
  --ink: #162831;
  --text: #31434b;
  --muted: #607178;
  --paper: #ffffff;
  --soft: #f3f6f4;
  --line: #d4dfdc;
  --accent: #007b84;
  --accent-dark: #075760;
  --cyan: #00a7c4;
  --gold: #e5a51a;
  --coral: #c84f3f;
  --blue: #2d68a0;
  --header-height: 66px;
  --page-width: 1120px;
  --serif: Georgia, "Times New Roman", serif;
  --sans: Aptos, "Segoe UI", Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
}

body {
  margin: 0;
  color: var(--text);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--accent-dark);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--accent);
}

a:focus-visible,
button:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 3px;
}

/* Hero */

.identity-hero {
  position: relative;
  display: grid;
  min-height: 340px;
  overflow: hidden;
  color: #fff;
  background: var(--ink);
  isolation: isolate;
}

.hero-image,
.hero-overlay {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-image {
  z-index: -2;
  object-fit: cover;
  object-position: center 46%;
}

.hero-overlay {
  z-index: -1;
  background: rgba(7, 26, 37, 0.58);
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: flex-end;
  padding-top: 72px;
  padding-bottom: 46px;
}

.section-kicker {
  margin: 0 0 12px;
  font-size: 13px;
  font-weight: 800;
  line-height: 1.3;
  text-transform: uppercase;
}


.identity-hero h1 {
  max-width: 820px;
  margin: 0;
  color: #fff;
  font-family: var(--serif);
  font-size: 56px;
  font-weight: 700;
  line-height: 1.08;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.28);
}

.hero-role {
  max-width: 680px;
  margin: 12px 0 0;
  color: rgba(255, 255, 255, 0.94);
  font-size: 21px;
  font-weight: 500;
  line-height: 1.4;
  text-shadow: 0 1px 8px rgba(0, 0, 0, 0.34);
}

/* Profile */

.profile-section {
  background: #fff;
  border-bottom: 1px solid var(--line);
}

.profile-intro {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: 48px;
  align-items: start;
  padding-top: 48px;
  padding-bottom: 52px;
}

.profile-photo {
  margin: 0;
}

.profile-photo img {
  width: 190px;
  height: auto;
  border: 1px solid #bac8c5;
  border-radius: 6px;
  box-shadow: 10px 10px 0 #dce9e4;
}

.profile-copy {
  max-width: 800px;
}

.profile-copy p {
  max-width: 68ch;
  margin: 0 0 16px;
}

.profile-copy .profile-lead {
  color: var(--ink);
  font-family: var(--serif);
  font-size: 24px;
  line-height: 1.45;
}

.profile-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin-top: 26px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 16px;
  gap: 9px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 4px;
  transition: background-color 160ms ease, color 160ms ease, border-color 160ms ease, transform 160ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button-primary {
  color: #fff;
  background: var(--accent-dark);
  border-color: var(--accent-dark);
}

.button-primary:hover {
  color: #fff;
  background: var(--accent);
  border-color: var(--accent);
}

.button-secondary {
  color: var(--accent-dark);
  background: #fff;
  border-color: #8eaead;
}

.button-secondary:hover {
  color: var(--ink);
  background: var(--soft);
  border-color: var(--accent-dark);
}

.text-action {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 8px 4px;
  gap: 8px;
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.profile-links a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #50636a;
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
}

.profile-links a:hover {
  color: var(--accent-dark);
}

/* Shared section heading */

.section-heading {
  max-width: 700px;
  margin-bottom: 38px;
}

.section-kicker {
  color: var(--accent);
}

.section-heading h2 {
  margin: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 38px;
  font-weight: 700;
  line-height: 1.15;
}

.section-heading > p:last-child {
  max-width: 60ch;
  margin: 12px 0 0;
  color: var(--muted);
}

/* Research */

.research-section {
  padding: 66px 0 72px;
  background: var(--soft);
}

.research-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 46px 54px;
}

.research-item {
  --item-accent: var(--accent);
  position: relative;
  padding: 20px 0 0;
  border-top: 3px solid var(--item-accent);
}


.research-spectral {
  --item-accent: var(--blue);
}

.research-proof {
  --item-accent: var(--coral);
}

.research-koopman {
  --item-accent: #a66f00;
}

.research-learning {
  --item-accent: #7d5677;
}


.research-number {
  display: block;
  margin-bottom: 13px;
  color: var(--item-accent);
  font-size: 13px;
  font-weight: 800;
}

.research-proof .research-number {
  color: #a23d31;
}

.research-koopman .research-number {
  color: #765000;
}

.research-item h3 {
  margin: 0 0 11px;
  font-family: var(--serif);
  font-size: 23px;
  font-weight: 700;
  line-height: 1.3;
}

.research-item h3 a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  color: var(--ink);
  text-decoration: none;
}

.research-item h3 i {
  flex: 0 0 auto;
  color: var(--item-accent);
  font-size: 14px;
  transition: transform 160ms ease;
}

.research-item h3 a:hover {
  color: var(--accent-dark);
}

.research-item h3 a:hover i {
  transform: translateX(4px);
}

.research-item p {
  max-width: 52ch;
  margin: 0;
  color: #53666d;
}

/* Background timeline */

.background-section {
  padding: 72px 0 78px;
  background: #fff;
}

.background-layout {
  display: grid;
  grid-template-columns: minmax(240px, 0.75fr) minmax(0, 1.5fr);
  gap: 84px;
  align-items: start;
}

.background-heading {
  position: sticky;
  top: calc(var(--header-height) + 36px);
  margin: 0;
}

.timeline {
  position: relative;
}

.timeline::before {
  position: absolute;
  top: 10px;
  bottom: 10px;
  left: 111px;
  width: 1px;
  content: "";
  background: var(--line);
}

.timeline-item {
  display: grid;
  grid-template-columns: 92px 18px minmax(0, 1fr);
  gap: 14px;
  min-height: 88px;
  padding-bottom: 26px;
}

.timeline-label {
  padding-top: 1px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 800;
  text-align: right;
  text-transform: uppercase;
}

.timeline-marker {
  position: relative;
  z-index: 1;
  width: 11px;
  height: 11px;
  margin: 6px auto 0;
  background: #fff;
  border: 3px solid var(--accent);
  border-radius: 50%;
}

.timeline-content h3 {
  margin: 0 0 5px;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 20px;
  line-height: 1.35;
}

.timeline-content p {
  max-width: 52ch;
  margin: 0;
  color: #5c6d73;
}

.timeline-content a {
  font-weight: 650;
}

@media (max-width: 920px) {
  .identity-hero {
    min-height: 300px;
  }

  .identity-hero h1 {
    font-size: 46px;
  }

  .hero-role {
    font-size: 19px;
  }

  .profile-intro {
    grid-template-columns: 160px minmax(0, 1fr);
    gap: 38px;
  }

  .profile-photo img {
    width: 160px;
  }

  .profile-copy .profile-lead {
    font-size: 22px;
  }

  .background-layout {
    grid-template-columns: 1fr;
    gap: 42px;
  }

  .background-heading {
    position: static;
  }
}

@media (max-width: 700px) {
  body {
    font-size: 16px;
  }

  .hero-content {
    padding-top: 58px;
    padding-bottom: 34px;
  }

  .identity-hero h1 {
    font-size: 40px;
  }

  .hero-role {
    max-width: 28ch;
    font-size: 18px;
  }

  .profile-intro {
    grid-template-columns: 1fr;
    gap: 34px;
    padding-top: 38px;
    padding-bottom: 44px;
  }

  .profile-photo {
    width: max-content;
    max-width: 100%;
    justify-self: center;
  }

  .profile-photo img {
    width: 156px;
  }

  .profile-copy .profile-lead {
    font-size: 21px;
  }

  .research-grid {
    grid-template-columns: 1fr;
    gap: 38px;
  }

  .section-heading h2 {
    font-size: 33px;
  }
}

@media (max-width: 520px) {
  .identity-hero {
    min-height: 280px;
  }

  .hero-image {
    object-position: 52% center;
  }

  .identity-hero h1 {
    font-size: 36px;
  }


  .profile-actions {
    align-items: stretch;
  }

  .profile-actions .button {
    flex: 1 1 auto;
  }

  .research-section,
  .background-section {
    padding-top: 54px;
    padding-bottom: 58px;
  }

  .research-item h3 {
    font-size: 21px;
  }

  .timeline::before {
    left: 82px;
  }

  .timeline-item {
    grid-template-columns: 65px 16px minmax(0, 1fr);
    gap: 10px;
  }

  .timeline-label {
    font-size: 11px;
  }

  .timeline-content h3 {
    font-size: 18px;
  }
}

@media print {
  .profile-actions,
  .profile-links {
    display: none;
  }

  .identity-hero {
    min-height: 0;
    color: var(--ink);
    background: #fff;
  }

  .hero-image,
  .hero-overlay {
    display: none;
  }

  .hero-content {
    padding: 20px 0;
  }

  .identity-hero h1,
  .hero-role {
    color: var(--ink);
    text-shadow: none;
  }
}