/* CARS · AeroSECURE — dc34-site's layout and headline scale, re-themed light in the ERAU
   colors sampled from the deck's diagrams (blue #0052a0, navy #1a2a55, gold #f9c900). */

:root {
  --bg: #f5f7fb;
  --surface: #fff;
  --navy: #1a2a55;
  --blue: #0052a0;
  --gold: #f9c900;
  --ink: #1a2a55; /* headlines */
  --text: #2f3b5c; /* body copy */
  --gray: #5f6880; /* secondary copy */
  --line: rgba(26, 42, 85, 0.12);
  --accent-line: rgba(0, 82, 160, 0.35);
  --wrap: 72rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  line-height: 1.5;
}

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

a {
  color: inherit;
}

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.muted {
  color: var(--gray);
}

.accent {
  color: var(--blue);
}

/* ---------- nav ---------- */

#nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  transition: background-color 0.3s, border-color 0.3s;
  border-bottom: 1px solid transparent;
}

#nav.scrolled {
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(20px);
  border-bottom-color: var(--line);
}

.nav-inner {
  height: 3.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--ink);
  text-decoration: none;
}

.nav-brand span {
  color: var(--gray);
  font-weight: 400;
}

.nav-links {
  display: flex;
  gap: 1.25rem;
  font-size: 0.875rem;
}

@media (max-width: 700px) {
  .nav-links a:not(.accent) {
    display: none;
  }
}

.nav-links a {
  color: var(--gray);
  text-decoration: none;
  transition: color 0.2s;
}

.nav-links a.accent {
  color: var(--blue);
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--ink);
}

.aerie-shot {
  margin-top: 1.75rem;
  aspect-ratio: 3 / 2;
}

.aerie-heading {
  margin-top: 2rem;
  color: var(--ink);
  font-weight: 600;
}

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

.lockup {
  width: clamp(15rem, 40vw, 30rem);
  margin: 0 auto 1.25rem;
}

.hero-logo {
  width: 100%;
  height: auto;
  display: block;
}

/* Quiet subtitle under the wordmark — present, not competing with it. */
.lockup-lab {
  margin: 0.45rem 0 0;
  font-size: clamp(0.55rem, 1.1vw, 0.68rem);
  font-weight: 400;
  letter-spacing: 0.2em;
  text-indent: 0.2em; /* balance the trailing letterspace */
  text-transform: uppercase;
  color: var(--gray);
  white-space: nowrap;
}

/* ---------- type ---------- */

.headline,
.headline-xl {
  font-weight: 800;
  margin: 0 0 1rem;
}

.headline {
  font-size: clamp(2.5rem, 6vw, 5rem);
  line-height: 1.05;
  letter-spacing: -0.03em;
}

.headline-xl {
  font-size: clamp(3rem, 8vw, 7rem);
  line-height: 1;
  letter-spacing: -0.04em;
}

.subheadline {
  font-size: clamp(1.1rem, 2vw, 1.5rem);
  color: var(--gray);
  max-width: 56rem;
  margin: 0 0 1rem;
}

.eyebrow {
  color: var(--blue);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin: 0 0 1rem;
}

.label {
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gray);
  margin: 0 0 1.25rem;
}

.tlp {
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gray);
  margin: 1.5rem 0 0;
}

.badge {
  display: inline-block;
  border: 1px solid rgba(197, 164, 74, 0.4);
  color: var(--gold);
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  border-radius: 999px;
  padding: 0.25rem 0.75rem;
  margin: 0 0 1rem;
}

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

.hero {
  padding: 5rem 0 2.25rem;
}

.talk {
  padding: 3rem 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 4rem;
}

@media (min-width: 768px) {
  .hero {
    padding: 6.5rem 0 3rem;
  }
  .talk {
    padding: 4rem 0;
  }
}

.talk.centered,
.hero {
  text-align: center;
}

.talk.centered .subheadline,
.talk.centered .prose,
.hero .subheadline,
.hero .prose,
.hero .slide-grid {
  margin-left: auto;
  margin-right: auto;
}

.prose {
  max-width: 56rem;
  margin: 1.5rem 0 0;
}

.prose p {
  color: var(--text);
  font-size: 1.125rem;
  line-height: 1.7;
  margin: 0 0 1.5rem;
  text-align: left;
}

/* ---------- slide links ---------- */

.slides-block {
  margin-top: 1.75rem;
  scroll-margin-top: 6rem;
}

.slide-grid {
  display: grid;
  gap: 0.75rem;
  max-width: 62rem;
}

@media (min-width: 640px) {
  .slide-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.slide-card {
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 0.75rem;
  padding: 1.25rem;
  transition: border-color 0.2s;
}

.slide-card:hover {
  border-color: var(--accent-line);
}

.slide-card-name {
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 0.75rem;
}

.slide-card-links {
  display: flex;
  gap: 1rem;
  font-size: 0.875rem;
}

.slide-card-links a {
  text-decoration: none;
  transition: color 0.2s;
}

.slide-card-links a:hover {
  color: var(--ink);
}

/* Compact timeline used inside a talk section (wider year labels, smaller text). */
.timeline.compact {
  max-width: 56rem;
  margin-top: 1.5rem;
  font-size: 0.9375rem;
}

.timeline.compact .tl-row {
  padding: 0.5rem 0;
}

@media (min-width: 640px) {
  .timeline.compact .tl-row {
    grid-template-columns: 8.5rem 1fr;
    gap: 1.25rem;
  }
}

.timeline.compact .tl-year {
  font-size: 0.875rem;
  font-weight: 600;
}

.tl-heading {
  margin: 0 0 0.25rem;
  font-size: 0.75rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gray);
}

/* ---------- "why" list ---------- */

.why {
  max-width: 56rem;
  margin: 1.75rem auto 0;
  text-align: left;
  border-left: 2px solid var(--accent-line);
  padding-left: 1.5rem;
}

.why-lead {
  margin: 0 0 0.85rem;
  color: var(--text);
  font-size: 1.125rem;
  line-height: 1.6;
}

.why-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.4rem 2rem;
}

@media (min-width: 700px) {
  .why-list {
    grid-template-columns: 1fr 1fr;
  }
}

.why-list li {
  position: relative;
  padding-left: 1.1rem;
  color: var(--gray);
  line-height: 1.5;
}

.why-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--blue);
}

/* The closing point is the summary one — give it the full width. */
.why-list li:last-child {
  grid-column: 1 / -1;
  color: var(--text);
}

/* ---------- facts ---------- */

.fact-grid {
  display: grid;
  gap: 1.5rem;
  margin-top: 1.75rem;
  max-width: 62rem;
  text-align: left;
}

@media (min-width: 640px) {
  .fact-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.talk.centered .fact-grid {
  margin-left: auto;
  margin-right: auto;
}

.fact {
  border-left: 2px solid var(--accent-line);
  padding-left: 1rem;
}

.fact-value {
  font-size: clamp(1.5rem, 3vw, 1.875rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0;
}

.fact-unit {
  font-size: 0.875rem;
  color: var(--gray);
  margin: 0.25rem 0 0;
}

/* ---------- research timeline ---------- */

.timeline {
  margin-top: 1.75rem;
  max-width: 62rem;
  margin-left: auto;
  margin-right: auto;
  text-align: left;
}

.tl-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.25rem;
  padding: 0.85rem 0;
  border-top: 1px solid var(--line);
}

@media (min-width: 640px) {
  .tl-row {
    grid-template-columns: 6rem 1fr;
    gap: 1.5rem;
  }
}

.tl-year {
  margin: 0;
  font-weight: 700;
  color: var(--blue);
  letter-spacing: -0.01em;
}

.tl-items p {
  margin: 0 0 0.35rem;
  color: var(--text);
  line-height: 1.5;
}

.tl-items p:last-child {
  margin-bottom: 0;
}

/* Slide diagrams are drawn on white — give them a light card instead of
   dropping a bright rectangle straight onto the dark page. */
.diagram {
  margin: 1.75rem auto 0;
  background: #fff;
  border-radius: 1rem;
  padding: 1rem;
  overflow-x: auto;
}

.diagram img {
  width: 100%;
  min-width: 34rem;
  height: auto;
}

/* Screenshots, unlike photos, must not be cropped — keep their own proportions. */
.photo-grid.screens {
  align-items: start; /* don't stretch figures to the tallest in the row */
}

.photo-grid.screens .media {
  aspect-ratio: auto;
  background: var(--surface);
}

.photo-grid.screens .media img {
  height: auto;
}

/* Image-only closer — the grid supplies its own top spacing. */
.closing .photo-grid {
  margin-top: 0;
}

/* ---------- media ---------- */

.photo-grid {
  display: grid;
  gap: 1rem;
  margin-top: 1.75rem;
}

@media (min-width: 640px) {
  .photo-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .photo-grid .media.wide {
    grid-column: span 2;
  }
}

.media {
  margin: 0;
  border-radius: 1rem;
  overflow: hidden;
  border: 1px solid var(--line);
  aspect-ratio: 4 / 3;
}

.media.wide {
  aspect-ratio: 16 / 9;
}

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero .media.wide {
  margin-top: 2rem;
}

.hero .hero-shot {
  margin-top: 1.75rem;
}

.hero .caption {
  margin-bottom: 1.75rem;
}

.media.team {
  margin-top: 1.75rem;
}

.caption {
  font-size: 0.875rem;
  color: var(--gray);
  margin: 1rem 0 0;
}

/* ---------- callout + actions ---------- */

.callout {
  margin-top: 1.75rem;
  max-width: 56rem;
  text-align: left;
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 1rem;
  padding: 2rem;
}

.talk.centered .callout {
  margin-left: auto;
  margin-right: auto;
}

.callout.with-image {
  max-width: 68rem;
  display: grid;
  gap: 2rem;
  align-items: center;
}

@media (min-width: 800px) {
  .callout.with-image {
    grid-template-columns: 1.3fr 1fr;
  }
}

.callout-figure {
  margin: 0;
  border-radius: 0.75rem;
  overflow: hidden;
  border: 1px solid var(--line);
}

.callout-figure img {
  width: 100%;
  height: auto;
  display: block;
}

.callout h3 {
  font-size: 1.25rem;
  margin: 0 0 0.75rem;
  color: var(--ink);
}

.callout p {
  color: var(--gray);
  margin: 0;
  line-height: 1.7;
}

.talk-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1.5rem;
}

.talk.centered .talk-actions {
  justify-content: center;
}

.btn {
  border-radius: 999px;
  padding: 0.625rem 1.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  background: var(--blue);
  color: #fff;
  transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.btn:hover {
  background: var(--navy);
}

.btn.ghost {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink);
}

.btn.ghost:hover {
  border-color: var(--blue);
  color: var(--blue);
}

.presenters {
  font-size: 0.875rem;
  color: var(--gray);
  margin: 1.5rem 0 0;
}

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

footer {
  border-top: 1px solid var(--line);
  padding: 4rem 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .footer-inner {
    flex-direction: row;
    align-items: flex-end;
    justify-content: space-between;
  }
}

.footer-org {
  font-weight: 600;
  color: var(--ink);
  margin: 0;
}

.footer-inner p {
  margin: 0;
  font-size: 0.875rem;
}

/* ---------- scroll reveal ----------
   Matches the promo site's rule: motion only above 1024px. */

@media (min-width: 1025px) {
  .reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
  }

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

  /* stagger siblings inside a grid without any JS bookkeeping */
  .slide-grid .reveal:nth-child(2),
  .fact-grid .reveal:nth-child(2),
  .photo-grid .reveal:nth-child(2) {
    transition-delay: 0.12s;
  }

  .slide-grid .reveal:nth-child(3),
  .fact-grid .reveal:nth-child(3),
  .photo-grid .reveal:nth-child(3) {
    transition-delay: 0.24s;
  }

  .photo-grid .reveal:nth-child(4) {
    transition-delay: 0.36s;
  }

  .prose .reveal:nth-child(2) {
    transition-delay: 0.15s;
  }

  .prose .reveal:nth-child(3) {
    transition-delay: 0.3s;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ---------- scrollbar ---------- */

::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--surface);
}

::-webkit-scrollbar-thumb {
  background: var(--navy);
  border-radius: 3px;
}

/* ---------- AeroSECURE additions ---------- */

/* Small slide diagrams: don't stretch them to the full column or force a scroll. */
.diagram.narrow {
  max-width: 28rem;
}

.diagram.narrow img {
  min-width: 0;
}

.photo-grid.cards figcaption {
  padding: 0.85rem 1rem 1rem;
  text-align: left;
}

.photo-grid.cards figcaption strong {
  display: block;
  color: var(--ink);
}

.photo-grid.cards figcaption span {
  display: block;
  margin-top: 0.25rem;
  font-size: 0.875rem;
  color: var(--gray);
  line-height: 1.5;
}

@media (min-width: 900px) {
  .photo-grid.cards {
    grid-template-columns: repeat(3, 1fr);
  }
}

.hero .talk-actions {
  justify-content: center;
}

/* The consortium's full name is much longer than DC34's lab line — let it wrap
   under the logo instead of running off the right edge. */
.lockup-lab {
  white-space: normal;
  line-height: 1.7;
}

/* Hero intro is two short lines; centered reads better under a centered headline. */
.hero .prose p {
  text-align: center;
}

/* Section figures (the OV-1) are full graphics, not photos — never crop them. */
.talk .media.wide.figure {
  aspect-ratio: auto;
}

.talk .media.wide.figure img {
  height: auto;
}

/* Cards: one image shape per grid so rows line up, and stretch to equal heights. */
.photo-grid.cards {
  align-items: stretch;
}

.photo-grid.cards .media img {
  aspect-ratio: 16 / 10;
  height: auto;
  object-fit: cover;
}

/* ---------- light theme: navy hero band ----------
   The AeroSECURE wordmark is white, so the hero stays dark — in ERAU navy. */

.hero {
  background: var(--navy);
}

.hero .headline-xl {
  color: #fff;
}

.hero .eyebrow {
  color: var(--gold);
}

.hero .lockup-lab,
.hero .presenters {
  color: rgba(255, 255, 255, 0.6);
}

.hero .prose p {
  color: rgba(255, 255, 255, 0.85);
}

.hero .btn:hover {
  background: #fff;
  color: var(--navy);
}

.hero .btn.ghost {
  border-color: rgba(255, 255, 255, 0.35);
  color: #fff;
}

.hero .btn.ghost:hover {
  border-color: var(--gold);
  color: var(--gold);
}

/* Diagrams and cards sit on white with a hairline, instead of glowing on dark. */
.diagram,
.photo-grid.cards .media {
  border: 1px solid var(--line);
  box-shadow: 0 1px 3px rgba(26, 42, 85, 0.06);
}

.photo-grid.cards .media {
  background: var(--surface);
}

/* Gold for decoration only — it fails contrast as text on white. */
.fact,
.why {
  border-left-color: var(--gold);
}

.why-list li::before {
  background: var(--gold);
}

/* Navy text can't sit transparent over the navy hero — keep the bar solid from the top. */
#nav {
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(20px);
  border-bottom-color: var(--line);
}