/* ── Reset ── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* ── Custom Properties ── */
:root {
  --bg-primary: #0B0F14;
  --bg-secondary: #11161C;
  --text-primary: #E6EDF3;
  --text-secondary: #9AA4AF;
  --text-muted: #6B7280;
  --accent: #2BC4A5;
  --divider: rgba(255,255,255,0.06);
  --radius: 12px;
  --container: 1200px;
  --space: 8px;
}

/* ── Base ── */
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'Red Hat Display', -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  font-weight: 400;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ── Typography ── */
h1 {
  font-size: 56px;
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.2;
}

h3 {
  font-size: 20px;
  font-weight: 500;
  line-height: 1.2;
}

small, .text-small {
  font-size: 14px;
}

/* ── Layout ── */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding-left: calc(var(--space) * 3);
  padding-right: calc(var(--space) * 3);
}

.section {
  padding: 100px 0;
  border-bottom: 1px solid var(--divider);
}

/* ── Fade-in animation ── */
.fade-in {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Focus ── */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* ── Links ── */
a {
  color: inherit;
  text-decoration: none;
}

/* ── Buttons ── */
.btn {
  display: inline-block;
  padding: calc(var(--space) * 1.5) calc(var(--space) * 4);
  font-family: 'Red Hat Display', -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 16px;
  font-weight: 500;
  line-height: 1.6;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
  text-align: center;
}

.btn-primary {
  background-color: var(--accent);
  color: var(--bg-primary);
}

.btn-primary:hover {
  background-color: #24a68c;
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border-color: rgba(255,255,255,0.12);
}

.btn-secondary:hover {
  border-color: rgba(255,255,255,0.28);
  background-color: rgba(255,255,255,0.04);
}

/* ── Label ── */
.label {
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: calc(var(--space) * 2);
}

/* ═══════════════════════════════
   HEADER / NAV
   ═══════════════════════════════ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background-color: rgba(11,15,20,0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--divider);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: calc(var(--space) * 1.25);
}

.logo-img {
  display: block;
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.logo-text {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
}

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

.nav-links {
  display: flex;
  gap: calc(var(--space) * 4);
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  font-weight: 400;
  color: var(--text-secondary);
  transition: color 0.2s ease;
}

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

/* ═══════════════════════════════
   HERO
   ═══════════════════════════════ */
.hero {
  min-height: 90vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--divider);
  padding-top: 64px;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 78% 48%, rgba(43,196,165,0.12), transparent 30%),
    linear-gradient(90deg, rgba(11,15,20,0) 0%, rgba(43,196,165,0.035) 100%);
  pointer-events: none;
}

.hero .container {
  position: relative;
  z-index: 1;
  width: 100%;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(360px, 0.96fr);
  gap: calc(var(--space) * 8);
  align-items: center;
  width: 100%;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 640px;
}

.hero-content h1 {
  margin-bottom: calc(var(--space) * 3);
}

.hero-content p {
  font-size: 18px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: calc(var(--space) * 5);
}

.hero-buttons {
  display: flex;
  gap: calc(var(--space) * 2);
}

/* ═══════════════════════════════
   HERO SIGNAL VISUAL
   ═══════════════════════════════ */
.hero-visual {
  position: relative;
  min-height: 520px;
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}

.signal-visual {
  position: relative;
  width: min(43vw, 540px);
  min-width: 360px;
  aspect-ratio: 1;
  isolation: isolate;
  transform-style: preserve-3d;
}

.signal-visual::before {
  content: '';
  position: absolute;
  inset: 10%;
  border-radius: 50%;
  background:
    radial-gradient(circle, rgba(43,196,165,0.2), rgba(43,196,165,0.035) 38%, transparent 68%),
    radial-gradient(circle at 62% 38%, rgba(126,231,255,0.16), transparent 32%);
  box-shadow:
    0 0 80px rgba(43,196,165,0.16),
    inset 0 0 50px rgba(43,196,165,0.08);
  opacity: 0.9;
}

.signal-visual::after {
  content: '';
  position: absolute;
  inset: 58% 6% 12%;
  z-index: 1;
  border: 1px solid rgba(43,196,165,0.12);
  border-radius: 50%;
  background:
    linear-gradient(rgba(43,196,165,0.13) 1px, transparent 1px),
    linear-gradient(90deg, rgba(43,196,165,0.13) 1px, transparent 1px);
  background-size: 28px 28px;
  -webkit-mask-image: radial-gradient(ellipse at center, #000 0%, #000 52%, transparent 74%);
  mask-image: radial-gradient(ellipse at center, #000 0%, #000 52%, transparent 74%);
  opacity: 0.32;
  transform: perspective(620px) rotateX(68deg) rotateZ(-12deg);
}

.signal-canvas {
  position: absolute;
  inset: 0;
  z-index: 3;
  display: block;
  width: 100%;
  height: 100%;
  filter: drop-shadow(0 0 24px rgba(43,196,165,0.14));
}

.signal-ring {
  position: absolute;
  z-index: 2;
  border: 1px solid rgba(43,196,165,0.16);
  border-radius: 50%;
  box-shadow: inset 0 0 28px rgba(43,196,165,0.05);
  transform: rotateX(64deg) rotateZ(-12deg);
  animation: signalRing 9s ease-in-out infinite;
}

.signal-ring-outer {
  inset: 5%;
}

.signal-ring-inner {
  inset: 22%;
  opacity: 0.55;
  animation-duration: 7.5s;
  animation-direction: reverse;
}

/* ═══════════════════════════════
   ABOUT
   ═══════════════════════════════ */
.about {
  background-color: var(--bg-secondary);
}

.about-inner {
  width: min(100%, 700px);
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

.about-inner .label {
  margin-bottom: calc(var(--space) * 2);
}

.about-inner h2 {
  margin-bottom: calc(var(--space) * 3);
}

.about-inner p {
  color: var(--text-secondary);
}

/* ═══════════════════════════════
   FOCUS ACCORDION
   ═══════════════════════════════ */
.focus-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: calc(var(--space) * 6);
}

.focus-accordion {
  border-bottom: 1px solid var(--divider);
}

.focus-accordion:first-child {
  border-top: 1px solid var(--divider);
}

.focus-accordion summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: calc(var(--space) * 3) 0;
  cursor: pointer;
  list-style: none;
  transition: color 0.2s ease;
}

.focus-accordion summary::-webkit-details-marker {
  display: none;
}

.focus-accordion summary::marker {
  display: none;
  content: '';
}

.focus-accordion summary h3 {
  color: var(--text-primary);
  transition: color 0.2s ease;
}

.focus-accordion summary:hover h3 {
  color: var(--accent);
}

.accordion-icon {
  position: relative;
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  margin-left: calc(var(--space) * 2);
}

.accordion-icon::before,
.accordion-icon::after {
  content: '';
  position: absolute;
  background-color: var(--text-muted);
  transition: transform 0.25s ease;
}

.accordion-icon::before {
  top: 50%;
  left: 0;
  width: 16px;
  height: 1.5px;
  transform: translateY(-50%);
}

.accordion-icon::after {
  top: 0;
  left: 50%;
  width: 1.5px;
  height: 16px;
  transform: translateX(-50%);
}

.focus-accordion[open] .accordion-icon::after {
  transform: translateX(-50%) rotate(90deg);
  opacity: 0;
}

.focus-accordion p {
  padding: 0 0 calc(var(--space) * 3) 0;
  color: var(--text-secondary);
  max-width: 640px;
  line-height: 1.6;
}

/* ═══════════════════════════════
   COMMUNITY LINKS
   ═══════════════════════════════ */
.community-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: calc(var(--space) * 3);
  margin-top: calc(var(--space) * 6);
}

.community-card {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: calc(var(--space) * 1.5);
  border: 1px solid var(--divider);
  border-radius: var(--radius);
  padding: calc(var(--space) * 6) calc(var(--space) * 4);
  font-size: 20px;
  font-weight: 500;
  color: var(--text-primary);
  transition: background-color 0.25s ease, border-color 0.25s ease;
  text-align: center;
}

.community-icon {
  flex-shrink: 0;
  opacity: 0.85;
}

.community-card:hover {
  background-color: rgba(255,255,255,0.025);
  border-color: rgba(255,255,255,0.12);
}

/* ═══════════════════════════════
   FOOTER
   ═══════════════════════════════ */
.site-footer {
  padding: calc(var(--space) * 5) 0;
  border-top: 1px solid var(--divider);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: calc(var(--space) * 4);
}

.footer-left {
  font-size: 14px;
  color: var(--text-muted);
  font-weight: 500;
}

.footer-right {
  font-size: 13px;
  color: var(--text-muted);
  max-width: 480px;
  text-align: right;
  line-height: 1.5;
}

/* ═══════════════════════════════
   ANIMATIONS
   ═══════════════════════════════ */
@keyframes signalRing {
  0%,
  100% {
    opacity: 0.52;
    transform: rotateX(64deg) rotateZ(-12deg) scale(0.98);
  }

  50% {
    opacity: 0.85;
    transform: rotateX(64deg) rotateZ(-12deg) scale(1.02);
  }
}

/* ═══════════════════════════════
   RESPONSIVE — TABLET
   ═══════════════════════════════ */
@media (max-width: 900px) {
  .nav-links {
    display: none;
  }

  .hero-grid {
    grid-template-columns: 1fr;
    gap: calc(var(--space) * 4);
  }

  .hero-content {
    max-width: 680px;
  }

  .hero-visual {
    min-height: 360px;
  }

  .signal-visual {
    width: min(72vw, 430px);
    min-width: 0;
  }

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

/* ═══════════════════════════════
   RESPONSIVE — MOBILE
   ═══════════════════════════════ */
@media (max-width: 640px) {
  h1 {
    font-size: 32px;
  }

  h2 {
    font-size: 24px;
  }

  .section {
    padding: 60px 0;
  }

  .container {
    padding-left: calc(var(--space) * 2.5);
    padding-right: calc(var(--space) * 2.5);
  }

  .hero {
    min-height: auto;
    padding-top: calc(64px + 60px);
    padding-bottom: 60px;
  }

  .hero-grid {
    display: block;
  }

  .hero-visual {
    display: none;
  }

  .hero::before {
    opacity: 0.45;
  }

  .hero-content h1 {
    max-width: 330px;
  }

  .hero-content p {
    font-size: 16px;
    max-width: 330px;
  }

  .hero-buttons {
    flex-direction: column;
    max-width: 340px;
  }

  .hero-buttons .btn {
    width: 100%;
  }

  .footer-inner {
    flex-direction: column;
    gap: calc(var(--space) * 2);
  }

  .footer-right {
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .fade-in,
  .signal-ring {
    animation: none;
    transition: none;
  }
}