/* ----------------------------------
   VisualAcoustic.ai Shared Styles
---------------------------------- */

:root{
  --bg:#000;
  --panel:#111;
  --txt:#fff;
  --brand:#ffcc00;
  --accent:#98d2e3;
  --accent2:#76b8ca;
  --shadow:0 0 10px rgba(0,0,0,0.5);
}

* {
  box-sizing: border-box;
}

a:link,
a:visited {
  color: var(--brand);
}

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--txt);
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.6;
  font-size: 16px;          /* base size; media queries adjust slightly */
}

/* ------------------------------
   TOP NAVIGATION BAR
------------------------------ */
.navbar {
  background: #000;
  border-bottom: 1px solid #333;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 20px;
  position: sticky;
  top: 0;
  z-index: 9999;
}

.navbar a {
  color: var(--brand);
  text-decoration: none;
  margin-left: 25px;
  font-size: 1.05rem;
}
.navbar a:hover {
  color: #fff;
}

.nav-left img {
  height: 55px;
  vertical-align: middle;
}

/* ------------------------------
   PAGE FRAME
------------------------------ */
.container {
  max-width: 950px;
  margin: 40px auto;
  padding: 25px;
  background: var(--panel);
  border-radius: 10px;
  box-shadow: var(--shadow);
  position: relative;
  z-index: 10;
}

h1, h2, h3 {
  color: var(--brand);
}

.hero {
  text-align: center;
  padding: 60px 20px 40px;
  position: relative;
  z-index: 10;
}

.hero h1 {
  font-size: 1.7rem;
  margin-bottom: 10px;
}

.hero p {
  font-size: 1.1rem;
  color: var(--accent2);
}

/* -----------------------------------------------
   FULL-SCREEN ANIMATED AI BACKGROUND LAYER
------------------------------------------------ */
.va-ai-bg {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
  background: radial-gradient(
      circle at 10% 20%,
      #10172f 0,
      #020617 55%,
      #000000 100%
  );
}

/* Fullscreen particle canvas */
#vaParticleCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

/* SVG clusters sitting above particles but behind content */
.va-ai-clusters {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.35;
}

.va-ai-clusters circle,
.va-ai-clusters line {
  fill: #38bdf8;
  stroke: #38bdf8;
  stroke-width: 0.5;
}

/* Subtle breathing animation for cluster dots */
.cluster circle {
  animation: vaDotPulse 4s ease-in-out infinite;
}

.cluster-head circle:nth-child(odd),
.cluster-graph circle:nth-child(even) {
  animation-delay: 2s;
}

@keyframes vaDotPulse {
  0%, 100% { opacity: 0.4; r: 1.8; }
  50%      { opacity: 1;   r: 2.4; }
}

/* All real page content MUST sit above background */
.va-ai-content,
footer {
  position: relative;
  z-index: 10;
}

/* Optional subtle highlight overlay */
.va-ai-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(
      circle at 80% 10%,
      rgba(56, 189, 248, 0.08),
      transparent 60%
  );
  pointer-events: none;
  mix-blend-mode: screen;
}

/* ----------------------------------
   RESPONSIVE TWEAKS (MOBILE / TABLET)
---------------------------------- */

/* Tablets and small laptops */
@media (max-width: 900px) {
  .container {
    margin: 30px 16px;
    padding: 20px;
  }

  .hero {
    padding: 40px 16px 24px;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .hero p {
    font-size: 1.05rem;
  }

  .navbar {
    padding: 10px 14px;
  }

  .navbar a {
    margin-left: 16px;
    font-size: 0.98rem;
  }
}

/* Phones */
@media (max-width: 600px) {
  body {
    font-size: 15px;  /* slightly smaller base, but viewport is correct now */
  }

  .navbar {
    flex-wrap: wrap;
    gap: 8px;
    padding: 8px 10px;
  }

  .nav-left img {
    height: 42px;
  }

  .navbar a {
    margin-left: 10px;
    font-size: 0.95rem;
  }

  .container {
    margin: 20px 10px;
    padding: 16px;
  }

  .hero {
    padding: 32px 12px 16px;
  }

  .hero h1 {
    font-size: 1.35rem;
  }

  .hero p {
    font-size: 0.98rem;
  }
}