@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&display=swap');

:root {
  --bg: #0b0d11;
  --bg-2: #050607;
  --text: #e2e4e9;
  --muted: #a5a8b3;
  --accent: #5ea1ff;        /* sky blue */
  --accent-2: #00bcd4;      /* cyan */
  --accent-light: #9cd8ff;
  --card-bg: rgba(20, 24, 32, 0.65);
  --border: rgba(255, 255, 255, 0.06);
  --shadow: 0 0 20px rgba(0, 0, 0, 0.3);
}

* { box-sizing: border-box; }
html, body { height: 100%; }

body {
  margin: 0;
  font-family: 'Inter', system-ui, sans-serif;
  background: radial-gradient(circle at top left, var(--bg), var(--bg-2));
  color: var(--text);
  line-height: 1.6;
  overflow-x: hidden;
  scroll-behavior: smooth;
}

/* Global aurora glow trail */
#fx-canvas {
  position: fixed;
  inset: 0;
  width: 100vw; height: 100vh;
  pointer-events: none;
  z-index: 0;
  mix-blend-mode: screen;
  opacity: 0.3;
}

/* Smooth cyan floating particles (behind content, above glow trail) */
#particle-canvas {
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  pointer-events: none;
  z-index: 1;
  opacity: 0.35;
}

/* ====== HERO ====== */
.hero {
  position: relative;
  display: grid;
  place-items: center;
  height: 42vh;
  min-height: 260px;
  perspective: 1000px;
  overflow: hidden;
  z-index: 2;
}

.hero-bg {
  position: absolute; inset: 0;
  transform-style: preserve-3d;
  transition: transform 0.12s ease-out;
  filter: saturate(1.05);
}

/* Aurora bands (aurora/AI vibe) */
.hero-bg .layer {
  position: absolute;
  top: 50%; left: 50%;
  width: 160vmax;
  height: 50vmax;
  transform: translate(-50%, -50%);
  border-radius: 1200px;
  filter: blur(30px);
  opacity: 0.18;
  pointer-events: none;
}

.hero-bg .l1 {
  background: linear-gradient(90deg,
    rgba(0,0,0,0) 0%,
    rgba(144,188,255,.55) 18%,
    rgba(0,188,212,.50) 50%,
    rgba(144,188,255,.45) 82%,
    rgba(0,0,0,0) 100%);
  transform: translate(-50%, -46%) rotate(18deg) translateZ(-120px);
  animation: aurora1 14s ease-in-out infinite alternate;
}
.hero-bg .l2 {
  background: linear-gradient(90deg,
    rgba(0,0,0,0) 0%,
    rgba(0,188,212,.45) 20%,
    rgba(160,210,255,.35) 52%,
    rgba(0,188,212,.40) 80%,
    rgba(0,0,0,0) 100%);
  transform: translate(-50%, -54%) rotate(-12deg) translateZ(-220px);
  animation: aurora2 17s ease-in-out infinite alternate;
}
.hero-bg .l3 {
  background: linear-gradient(90deg,
    rgba(0,0,0,0) 0%,
    rgba(160,210,255,.30) 25%,
    rgba(120,180,240,.28) 50%,
    rgba(160,210,255,.26) 75%,
    rgba(0,0,0,0) 100%);
  transform: translate(-50%, -50%) rotate(6deg) translateZ(-320px);
  opacity: 0.14;
  animation: aurora3 22s ease-in-out infinite alternate;
}

@keyframes aurora1 {
  0% { transform: translate(-50%,-46%) rotate(18deg) translateZ(-120px); }
  100% { transform: translate(calc(-50% + 1.5%),-45%) rotate(20deg) translateZ(-120px); }
}
@keyframes aurora2 {
  0% { transform: translate(-50%,-54%) rotate(-12deg) translateZ(-220px); }
  100% { transform: translate(calc(-50% - 2%),-55%) rotate(-9deg) translateZ(-220px); }
}
@keyframes aurora3 {
  0% { transform: translate(-50%,-50%) rotate(6deg) translateZ(-320px); }
  100% { transform: translate(calc(-50% + 1%),-49%) rotate(8deg) translateZ(-320px); }
}

.hero-inner {
  position: relative; z-index: 3;
  text-align: center;
  padding: 12px 16px;
}

.hero h1 {
  margin: 0 0 6px;
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  color: var(--accent-light);
  text-shadow: 0 0 12px rgba(0, 188, 212, 0.25);
  cursor: pointer; /* for the quantum collapse dblclick */
}
.hero small {
  display: block;
  color: var(--muted);
  margin-bottom: 14px;
}
.hero-nav a {
  margin: 0 10px;
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  transition: color .2s ease, text-shadow .2s ease;
}
.hero-nav a:hover { color: #fff; text-shadow: 0 0 8px var(--accent); }

/* Quantum flash particle (cinematic) */
.collapse-flash {
  position: absolute;
  width: 20px; height: 20px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,1) 0%, rgba(255,255,255,0) 70%);
  pointer-events: none;
  transform: translate(-50%, -50%) scale(1);
  animation: flashExpand 1.5s ease-out forwards;
  z-index: 999;
}
@keyframes flashExpand {
  0%   { opacity: 1; transform: translate(-50%, -50%) scale(1);  filter: blur(0px); }
  30%  { opacity: 1; transform: translate(-50%, -50%) scale(15); filter: blur(6px); }
  100% { opacity: 0; transform: translate(-50%, -50%) scale(40); filter: blur(12px); }
}

/* ====== MAIN CONTENT ====== */
.wrap {
  max-width: 900px;
  margin: 0 auto;
  padding: 20px 24px;
  position: relative;
  z-index: 2; /* above particles */
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 24px 28px;
  margin: 28px 0;
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
  transition: transform .25s ease, box-shadow .25s ease;
  transform-style: preserve-3d;
  will-change: transform;
  overflow: hidden;
}
.card:hover { box-shadow: 0 0 28px rgba(0,188,212,0.25); }

h2 { margin: 0 0 8px; color: var(--accent); }
a  { color: var(--accent); text-decoration: none; transition: color .2s ease, text-shadow .2s ease; }
a:hover { color: #fff; text-shadow: 0 0 8px var(--accent); }

ul { list-style: none; padding: 0; margin: 0; }
li { margin: 10px 0; }

.fade-in {
  opacity: 0;
  transform: translateY(26px);
  animation: fadeInUp 800ms forwards;
  animation-play-state: paused;
}
@keyframes fadeInUp { to { opacity: 1; transform: translateY(0); } }

/* ====== FOOTER ====== */
footer {
  text-align: center;
  color: #a9a1c7;
  padding: 44px 0 28px;
  border-top: 1px solid var(--border);
  position: relative;
  z-index: 3;
}
footer .social a {
  margin: 0 12px;
  color: var(--accent-light);
  font-weight: 500;
}
footer .social a:hover { color: #fff; text-shadow: 0 0 8px var(--accent); }

footer .to-top {
  position: fixed;
  right: 16px; bottom: 16px;
  background: rgba(40,45,60,0.55);
  border: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border-radius: 10px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(6px);
  transition: transform .2s ease, box-shadow .2s ease, opacity .2s ease;
  opacity: 0.85;
}
footer .to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 0 20px rgba(0,188,212,0.25);
}

/* Responsive */
@media (max-width: 640px) {
  .wrap { padding: 12px 16px; }
  .card { margin: 20px 0; padding: 18px 20px; }
}