:root {
  --ink: #202124;
  --muted: #5f6368;
  --line: #e0e3e7;
  --soft: #f8fafd;
  --blue: #4285f4;
  --green: #34a853;
  --yellow: #fbbc04;
  --red: #ea4335;
  --charcoal: #1d1d1d;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: #fff;
  overflow-x: hidden;
}

button {
  font: inherit;
}

a {
  color: inherit;
}

.scroll-meter {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 20;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--blue), var(--green), var(--yellow), var(--red));
  transform: scaleX(0);
  transform-origin: left;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 76px;
  padding: 12px clamp(20px, 5vw, 64px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(16px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  text-decoration: none;
}

.brand strong,
.brand small {
  display: block;
}

.brand strong {
  font-size: 18px;
}

.brand small {
  margin-top: 2px;
  color: var(--muted);
  font-size: 13px;
}

.mark {
  position: relative;
  display: block;
  width: 42px;
  height: 32px;
}

.arm {
  position: absolute;
  width: 24px;
  height: 11px;
  border-radius: 10px;
  outline: 2px solid var(--ink);
}

.red {
  left: 3px;
  top: 6px;
  background: var(--red);
  transform: rotate(-35deg);
}

.blue {
  left: 3px;
  bottom: 6px;
  background: var(--blue);
  transform: rotate(35deg);
}

.green {
  right: 3px;
  top: 6px;
  background: var(--green);
  transform: rotate(35deg);
}

.yellow {
  right: 3px;
  bottom: 6px;
  background: var(--yellow);
  transform: rotate(-35deg);
}

nav {
  display: flex;
  gap: 22px;
}

nav a {
  position: relative;
  color: var(--muted);
  font-size: 15px;
  font-weight: 700;
  text-decoration: none;
}

nav a:hover,
nav a.is-active {
  color: var(--blue);
}

nav a.is-active::after {
  position: absolute;
  right: 0;
  bottom: -9px;
  left: 0;
  height: 3px;
  border-radius: 99px;
  background: var(--blue);
  content: "";
}

.hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(420px, 1.05fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: center;
  padding: clamp(42px, 7vw, 86px) clamp(20px, 5vw, 64px) 46px;
  min-height: min(820px, calc(100vh - 76px));
  background:
    linear-gradient(115deg, rgba(66, 133, 244, 0.08), transparent 34%),
    linear-gradient(245deg, rgba(52, 168, 83, 0.08), transparent 30%),
    #fff;
}

.hero::after {
  position: absolute;
  right: clamp(20px, 5vw, 64px);
  bottom: 0;
  left: clamp(20px, 5vw, 64px);
  height: 1px;
  background: linear-gradient(90deg, var(--blue), var(--green), var(--yellow), var(--red));
  content: "";
}

.hero-copy,
.hero-art,
.about-grid > *,
.split > *,
.contact-panel > * {
  min-width: 0;
}

.eyebrow,
.section-label {
  margin: 0 0 12px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 660px;
  margin-bottom: 22px;
  font-size: clamp(43px, 6vw, 76px);
  line-height: 1.02;
  letter-spacing: 0;
  overflow-wrap: break-word;
}

h2 {
  margin-bottom: 18px;
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.08;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 20px;
  line-height: 1.24;
}

.lead {
  max-width: 620px;
  color: var(--muted);
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.52;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  max-width: 620px;
  margin-top: 26px;
}

.stat-button {
  min-width: 0;
  padding: 14px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
  text-align: left;
  cursor: pointer;
}

.stat-button strong,
.stat-button span {
  display: block;
}

.stat-button strong {
  font-size: 22px;
}

.stat-button span {
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  overflow-wrap: anywhere;
}

.stat-button:hover,
.stat-button:focus-visible,
.topic-chip:hover,
.topic-chip:focus-visible,
.filter-button:hover,
.filter-button:focus-visible {
  border-color: var(--blue);
  outline: none;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-weight: 800;
  text-decoration: none;
}

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

.button.secondary {
  background: #fff;
  color: var(--ink);
}

.button.large {
  align-self: center;
  min-width: 220px;
}

.hero-art img,
.banner img {
  display: block;
  width: 100%;
  height: auto;
}

.hero-art {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid rgba(32, 33, 36, 0.88);
  border-radius: 8px;
  background: var(--charcoal);
  box-shadow: 0 30px 90px rgba(32, 33, 36, 0.22);
  transform: perspective(900px) rotateX(var(--tilt-x, 0deg)) rotateY(var(--tilt-y, 0deg));
  transition: transform 180ms ease, box-shadow 180ms ease;
}

.hero-art::before {
  position: absolute;
  inset: 0;
  z-index: 2;
  border: 10px solid transparent;
  border-image: linear-gradient(135deg, var(--blue), var(--green), var(--yellow), var(--red)) 1;
  opacity: 0.9;
  pointer-events: none;
  content: "";
}

.hero-video iframe {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 178%;
  height: 100%;
  border: 0;
  transform: translate(-50%, -50%);
}

.section {
  padding: clamp(48px, 7vw, 88px) clamp(20px, 5vw, 64px);
  border-top: 1px solid var(--line);
}

.about-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.8fr) minmax(360px, 1.2fr);
  gap: clamp(28px, 5vw, 72px);
}

.about-grid p,
.contact-panel p {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.62;
}

.principles {
  display: grid;
  gap: 14px;
}

.principles article,
.event-card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.dot {
  display: block;
  width: 30px;
  height: 5px;
  margin-bottom: 18px;
  border-radius: 99px;
}

.blue-dot {
  background: var(--blue);
}

.green-dot {
  background: var(--green);
}

.yellow-dot {
  background: var(--yellow);
}

.banner {
  padding: 0 clamp(20px, 5vw, 64px) clamp(48px, 7vw, 88px);
}

.banner img {
  overflow: hidden;
  border-radius: 8px;
  background: var(--charcoal);
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}

.text-link {
  color: var(--blue);
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: -6px 0 24px;
}

.filter-button,
.topic-chip {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: #fff;
  font-weight: 800;
  cursor: pointer;
}

.filter-button.is-active {
  border-color: var(--blue);
  color: #fff;
  background: var(--blue);
}

.event-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.event-card p {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.55;
}

.event-card {
  transform: perspective(900px) rotateX(var(--tilt-x, 0deg)) rotateY(var(--tilt-y, 0deg));
  transition: opacity 180ms ease, transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.event-card:hover {
  border-color: #c8d7f6;
  box-shadow: 0 18px 42px rgba(32, 33, 36, 0.08);
}

.event-card.is-hidden {
  display: none;
}

.tag {
  display: inline-flex;
  margin-bottom: 16px;
  padding: 5px 9px;
  border-radius: 8px;
  color: #7a5900;
  background: #fff3c4;
  font-size: 13px;
  font-weight: 800;
}

.split {
  display: grid;
  grid-template-columns: minmax(260px, 0.55fr) minmax(360px, 1fr);
  gap: 36px;
  align-items: start;
  background: var(--soft);
}

.topic-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.topic-list span {
  display: none;
}

.topic-chip.is-active {
  border-color: var(--green);
  color: #fff;
  background: var(--green);
}

.lab-copy {
  max-width: 480px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.58;
}

.lab-card {
  margin-top: 18px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.lab-card span {
  display: inline-flex;
  margin-bottom: 14px;
  padding: 5px 9px;
  border-radius: 8px;
  color: #0f5f2b;
  background: #dff4e6;
  font-size: 13px;
  font-weight: 800;
}

.lab-card p {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.55;
}

.contact-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 32px;
  align-items: center;
}

.contact-lines {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 22px;
  margin-top: 22px;
}

.contact-lines a {
  color: var(--blue);
  font-weight: 800;
  text-decoration: none;
}

.join-card {
  display: grid;
  gap: 12px;
  width: min(100%, 340px);
}

.join-card img {
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

.toast {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 30;
  padding: 12px 14px;
  border-radius: 8px;
  color: #fff;
  background: var(--charcoal);
  box-shadow: 0 14px 42px rgba(32, 33, 36, 0.18);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 160ms ease, transform 160ms ease;
  pointer-events: none;
}

.toast.is-visible {
  opacity: 1;
  transform: translateY(0);
}

footer {
  display: flex;
  gap: 24px;
  justify-content: space-between;
  padding: 30px clamp(20px, 5vw, 64px);
  color: #c8ccd1;
  background: var(--charcoal);
}

footer strong,
footer span {
  display: block;
}

footer span {
  margin-top: 4px;
}

footer p {
  max-width: 560px;
  margin: 0;
  line-height: 1.5;
}

@media (max-width: 900px) {
  .hero,
  .about-grid,
  .split,
  .contact-panel {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    overflow: hidden;
  }

  .event-grid {
    grid-template-columns: 1fr;
  }

  .button.large {
    justify-self: start;
  }

  .hero-stats {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 14px;
  }

  nav {
    width: 100%;
    justify-content: space-between;
    gap: 10px;
  }

  .hero {
    padding-top: 34px;
    width: 100%;
  }

  h1 {
    font-size: 33px;
    line-height: 1.1;
  }

  h2 {
    font-size: 28px;
  }

  .lead,
  .about-grid p,
  .contact-panel p {
    font-size: 16px;
  }

  .hero-copy,
  .hero-art,
  .section > *,
  footer > * {
    max-width: 340px;
  }

  .hero-art img {
    width: 340px;
    max-width: 100%;
  }

  .button {
    padding-inline: 14px;
  }

  .filter-button,
  .topic-chip {
    flex: 1 1 130px;
  }

  footer,
  .section-heading {
    align-items: flex-start;
    flex-direction: column;
  }
}