:root {
  --green: #2E7D32;
  --green-dark: #1f5b28;
  --charcoal: #263238;
  --slate: #607D8B;
  --warm-white: #FAFAF7;
  --copper: #B87333;
  --white: #ffffff;
  --border: rgba(38, 50, 56, 0.14);
  --shadow: 0 14px 32px rgba(38, 50, 56, 0.08);
  --serif: "Cormorant Garamond", Georgia, "Times New Roman", serif;
  --sans: "Source Sans 3", "Segoe UI", Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--charcoal);
  background: var(--warm-white);
  font-family: var(--sans);
  line-height: 1.6;
}

a {
  color: inherit;
}

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

.container {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

/* =========================
   HEADER + NAVIGATION
   ========================= */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(250, 250, 247, 0.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.site-header.scrolled {
  border-bottom-color: var(--border);
  box-shadow: 0 6px 24px rgba(38, 50, 56, 0.06);
}

.nav-wrap {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  min-width: 0;
}

.brand img {
  width: 50px;
  height: auto;
  object-fit: contain;
  flex-shrink: 0;
}

.brand-copy {
  display: grid;
  line-height: 1.05;
}

.brand-copy strong {
  font-family: var(--serif);
  color: var(--green-dark);
  font-size: 1.9rem;
  font-weight: 600;
  line-height: 1;
}

.brand-copy small {
  max-width: 310px;
  margin-top: 6px;
  color: var(--charcoal);
  font-size: 0.78rem;
  line-height: 1.3;
}

.main-nav {
  display: flex;
  gap: 32px;
  align-items: center;
}

.main-nav a {
  text-decoration: none;
  font-size: 0.93rem;
  font-weight: 600;
  position: relative;
}

.main-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: -8px;
  height: 2px;
  background: var(--green);
  transition: right 0.2s ease;
}

.main-nav a:hover::after,
.main-nav a:focus-visible::after {
  right: 0;
}

.menu-toggle {
  display: none;
  border: 0;
  background: transparent;
  font-size: 1.5rem;
  color: var(--green-dark);
}

/* =========================
   HERO
   ========================= */

.hero {
  position: relative;
  overflow: hidden;
  min-height: 520px;
  display: grid;
  align-items: center;
  border-bottom: 1px solid var(--border);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    var(--warm-white) 0 54%,
    rgba(250, 250, 247, 0.4) 100%
  );
}

.hero-lines {
  position: absolute;
  width: 66%;
  height: 78%;
  right: -8%;
  bottom: -17%;
  opacity: 0.42;
  background: repeating-radial-gradient(
    ellipse at 30% 60%,
    transparent 0 18px,
    rgba(46, 125, 50, 0.1) 19px 20px,
    transparent 21px 36px
  );
  transform: rotate(-8deg);
}

.hero-grid {
  position: relative;
  z-index: 2;
}

.hero-copy {
  max-width: 760px;
  padding: 66px 0 76px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--green);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.78rem;
  font-weight: 600;
}

.eyebrow.light {
  color: #cfe3d1;
}

h1,
h2,
h3 {
  font-family: var(--serif);
  color: var(--green-dark);
  line-height: 1.05;
  margin-top: 0;
}

h1 {
  font-size: clamp(3.15rem, 5vw, 5rem);
  max-width: 800px;
  margin-bottom: 22px;
  font-weight: 500;
  line-height: 1.03;
}

h2 {
  font-size: clamp(2.4rem, 4.2vw, 3.8rem);
  margin-bottom: 16px;
  font-weight: 600;
}

h3 {
  font-size: 1.72rem;
  margin-bottom: 10px;
  font-weight: 600;
}

.hero-lede {
  max-width: 620px;
  font-size: 1.08rem;
  line-height: 1.6;
  margin: 0 0 28px;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 18px;
  padding: 13px 20px;
  border-radius: 5px;
  text-decoration: none;
  font-weight: 600;
  transition:
    transform 0.2s ease,
    background 0.2s ease,
    box-shadow 0.2s ease;
}

.button.primary {
  background: var(--green-dark);
  color: white;
  box-shadow: 0 8px 18px rgba(31, 91, 40, 0.16);
}

.button.primary:hover {
  transform: translateY(-2px);
  background: var(--green);
  box-shadow: 0 12px 24px rgba(31, 91, 40, 0.2);
}

/* =========================
   GENERAL SECTIONS
   ========================= */

.section {
  padding: 84px 0;
}

.section.alt {
  background: #f5f3ed;
}

.section-heading {
  max-width: 760px;
  margin: 0 auto 42px;
  text-align: center;
}

.section-heading.left {
  text-align: left;
  margin: 0 0 32px;
}

.section-heading p:last-child {
  margin-bottom: 0;
}

/* =========================
   RESEARCH
   ========================= */

.research-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.research-card {
  background: rgba(255, 255, 255, 0.62);
  border: 1px solid var(--border);
  padding: 32px 28px;
  border-radius: 8px;
  min-height: 305px;
  transition:
    transform 0.25s ease,
    border-color 0.25s ease,
    box-shadow 0.25s ease;
}

.research-card:hover {
  transform: translateY(-4px);
  border-color: rgba(46, 125, 50, 0.45);
  box-shadow: var(--shadow);
}

.research-card p {
  min-height: 88px;
}

.research-card > a {
  color: var(--green-dark);
  font-weight: 600;
  text-decoration: none;
}

.icon-shell {
  width: 70px;
  height: 70px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: #edf4eb;
  margin-bottom: 22px;
}

.icon-shell svg {
  width: 46px;
  height: 46px;
  fill: none;
  stroke: var(--green-dark);
  stroke-width: 2.6;
  stroke-linecap: round;
  stroke-linejoin: round;
  overflow: visible;
}

/* Sustainable Materials animation */

.microstructure svg path {
  stroke-dasharray: 260;
  stroke-dashoffset: 0;
}

.research-card:hover .microstructure svg path {
  animation: draw-network 0.8s ease forwards;
}

.research-card:hover .microstructure svg circle {
  animation: node-pulse 0.8s ease;
}

@keyframes draw-network {
  from {
    stroke-dashoffset: 260;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes node-pulse {
  50% {
    transform: scale(1.18);
    transform-origin: center;
  }
}

/* Resilient Infrastructure animation */

.truss-icon .truss-line {
  stroke-dasharray: 240;
  stroke-dashoffset: 0;
}

.research-card:hover .truss-icon .truss-line {
  animation: draw-truss 0.85s ease forwards;
}

@keyframes draw-truss {
  from {
    stroke-dashoffset: 240;
  }
  to {
    stroke-dashoffset: 0;
  }
}

/* Engineering Innovation animation */

.innovation-icon .bulb-outline {
  stroke-dasharray: 220;
  stroke-dashoffset: 0;
}

.innovation-icon .bulb-base {
  stroke-dasharray: 50;
  stroke-dashoffset: 0;
}

.innovation-icon .bulb-rays {
  stroke-dasharray: 80;
  stroke-dashoffset: 0;
}

.innovation-icon .bulb-filament {
  stroke-dasharray: 180;
  stroke-dashoffset: 0;
}

.innovation-icon .bulb-stem {
  stroke-dasharray: 60;
  stroke-dashoffset: 0;
}

.research-card:hover .innovation-icon .bulb-outline {
  animation: draw-bulb-outline 0.85s ease forwards;
}

.research-card:hover .innovation-icon .bulb-base {
  animation: draw-bulb-base 0.85s ease forwards;
}

.research-card:hover .innovation-icon .bulb-filament {
  animation: draw-bulb-filament 0.85s ease forwards;
}

.research-card:hover .innovation-icon .bulb-stem {
  animation: draw-bulb-stem 0.85s ease forwards;
}

.research-card:hover .innovation-icon .bulb-rays {
  animation: pulse-bulb-rays 0.85s ease forwards;
}

@keyframes draw-bulb-outline {
  from {
    stroke-dashoffset: 220;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes draw-bulb-base {
  from {
    stroke-dashoffset: 50;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes draw-bulb-filament {
  from {
    stroke-dashoffset: 180;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes draw-bulb-stem {
  from {
    stroke-dashoffset: 60;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes pulse-bulb-rays {
  0% {
    opacity: 0.2;
    stroke-dashoffset: 80;
  }
  50% {
    opacity: 1;
  }
  100% {
    opacity: 1;
    stroke-dashoffset: 0;
  }
}

/* =========================
   PEOPLE
   ========================= */

.people-grid {
  display: grid;
  grid-template-columns: 0.72fr 1.28fr;
  gap: 64px;
  align-items: start;
}

.people-photo {
  width: 100%;
  max-width: 430px;
  justify-self: center;
}

.people-photo img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  object-position: center top;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.people-copy {
  padding-top: 4px;
}

.people-copy .role {
  color: var(--copper);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 600;
  margin-top: -4px;
}

.bio-placeholder {
  max-width: 760px;
  margin-bottom: 0;
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.profile-links a {
  text-decoration: none;
  border-bottom: 1px solid var(--green);
  padding: 5px 0;
  margin-right: 18px;
  font-weight: 600;
}

.credentials-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 42px;
  margin-top: 36px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.credentials-block h3 {
  font-size: 1.5rem;
  margin-bottom: 18px;
}

.credentials-block p {
  margin: 0 0 16px;
  font-size: 0.95rem;
  line-height: 1.5;
}

.credentials-block strong {
  color: var(--charcoal);
  font-weight: 600;
}

/* =========================
   PUBLICATIONS + NEWS
   ========================= */

.split-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
}

.publication-list,
.news-list {
  display: grid;
  gap: 10px;
}

.publication-item {
  display: grid;
  grid-template-columns: 54px 1fr;
  gap: 18px;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
}

.publication-item h3,
.news-item h3 {
  color: var(--charcoal);
  font-family: var(--sans);
  font-size: 1.05rem;
  line-height: 1.3;
  margin-bottom: 5px;
}

.publication-item p,
.news-item p {
  margin: 0;
  color: var(--slate);
}

.doc-icon {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  background: #f2efe8;
  color: var(--green-dark);
  border-radius: 5px;
  font-size: 1.4rem;
}

.news-item {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 20px;
  padding: 18px 0;
  border-bottom: 1px solid var(--border);
}

.news-item time {
  color: var(--green-dark);
  font-family: var(--serif);
  font-size: 1.45rem;
}

/* =========================
   CONTACT
   ========================= */

.contact-section {
  background: var(--green-dark);
  color: white;
  padding: 72px 0;
}

.contact-section h2 {
  color: white;
}

.contact-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 72px;
}

.contact-placeholder {
  border-left: 1px solid rgba(255, 255, 255, 0.25);
  padding-left: 40px;
}

.contact-placeholder p {
  margin: 0 0 18px;
}

.contact-section a {
  color: white;
  text-underline-offset: 3px;
}

/* =========================
   FOOTER
   ========================= */

.site-footer {
  background: #173f20;
  color: rgba(255, 255, 255, 0.82);
  padding: 28px 0;
}

.footer-grid {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-brand img {
  width: 38px;
  height: auto;
  object-fit: contain;
  filter: brightness(0) invert(1);
}

.footer-brand div {
  display: grid;
}

.footer-brand strong {
  font-family: var(--serif);
  color: white;
  font-size: 1.35rem;
}

.footer-brand span {
  font-size: 0.82rem;
  max-width: 300px;
}

.site-footer p {
  margin: 0;
  font-size: 0.86rem;
}

/* =========================
   SCROLL REVEAL
   ========================= */

.reveal {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* =========================
   ACCESSIBILITY
   ========================= */

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

  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* =========================
   TABLET
   ========================= */

@media (max-width: 880px) {
  .brand-copy small {
    display: none;
  }

  .menu-toggle {
    display: block;
  }

  .main-nav {
    position: absolute;
    left: 20px;
    right: 20px;
    top: 76px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    background: var(--warm-white);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav a {
    padding: 12px;
  }

  .main-nav a::after {
    display: none;
  }

  .hero {
    min-height: 510px;
  }

  .research-grid,
  .people-grid,
  .split-grid,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .people-grid,
  .split-grid,
  .contact-grid {
    gap: 42px;
  }

  .research-card p {
    min-height: auto;
  }

  .people-photo {
    max-width: 360px;
  }

  .credentials-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .contact-placeholder {
    border-left: 0;
    padding-left: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.25);
    padding-top: 28px;
  }

  .footer-grid {
    align-items: flex-start;
    flex-direction: column;
  }
}

/* =========================
   MOBILE
   ========================= */

@media (max-width: 560px) {
  .container {
    width: min(100% - 28px, 1180px);
  }

  .nav-wrap {
    min-height: 68px;
  }

  .brand img {
    width: 40px;
  }

  .brand-copy strong {
    font-size: 1.5rem;
  }

  h1 {
    font-size: clamp(2.8rem, 13vw, 3.5rem);
    line-height: 1.04;
  }

  h2 {
    font-size: 2.5rem;
  }

  .hero {
    min-height: 500px;
  }

  .hero-copy {
    padding: 54px 0 64px;
  }

  .hero-lines {
    width: 100%;
    right: -38%;
    opacity: 0.34;
  }

  .section {
    padding: 64px 0;
  }

  .research-card {
    min-height: auto;
  }

  .people-photo {
    max-width: 100%;
  }

  .credentials-grid {
    margin-top: 30px;
    padding-top: 24px;
  }
}