:root{
  --bg:#0a0f1e;
  --bg-alt:#0d1326;
  --text:#e6eefc;
  --muted:#9bb0d7;
  --accent:#6ac1ff;
  --accent-2:#9d7bff;
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family:Montserrat,system-ui,-apple-system,Segoe UI,Roboto,"Helvetica Neue",Arial,"Noto Sans","Liberation Sans",sans-serif;
  color:var(--text);
  background:radial-gradient(1200px 600px at 20% 20%,#0b1228 0,var(--bg) 60%),radial-gradient(800px 400px at 80% 5%,#0b1022 0,var(--bg-alt) 60%),linear-gradient(180deg,var(--bg),var(--bg-alt));
  overflow-x:hidden;
}
#starfield{
  position:fixed;inset:0;z-index:-1;
}
.site-header{
  display:flex;align-items:center;gap:16px;
  padding:24px 28px;border-bottom:1px solid #1b2545;background:rgba(6,10,24,.6);backdrop-filter:saturate(140%) blur(6px);
}
.logo{
  width:56px;height:56px;object-fit:contain;
  background:#fff;padding:6px;border-radius:12px;
  box-shadow:0 0 0 1px rgba(255,255,255,.6), 0 0 10px rgba(106,193,255,.35);
}
.titles h1{margin:0;font-weight:800;letter-spacing:.2px}
.subtitle{margin:2px 0 0;color:var(--muted);font-weight:600}
.cta{
  margin-left:auto;
  display:inline-flex;align-items:center;gap:8px;
  padding:10px 14px;border-radius:10px;
  color:#071225;background:linear-gradient(90deg,var(--accent),var(--accent-2));
  text-decoration:none;font-weight:700;box-shadow:0 6px 20px rgba(106,193,255,.35), inset 0 0 18px rgba(255,255,255,.2);
}
.cta-secondary{
  margin-left:0;
  margin-top:10px;
  background:linear-gradient(90deg,#d5e9ff,#ffffff);
  color:#091325;
  box-shadow:0 6px 16px rgba(15,40,80,.25), inset 0 0 0 1px rgba(9,19,37,.1);
}
main{max-width:1200px;margin:26px auto;padding:0 24px}
.card{
  background:linear-gradient(180deg,rgba(13,19,38,.8),rgba(9,13,28,.8));
  border:1px solid #1b2545;border-radius:18px;padding:18px 20px;margin-bottom:20px;
  box-shadow:0 8px 24px rgba(16,24,48,.35);
}
.grid{
  display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px;margin-top:12px;
}
.video-card{
  background:#0c1326;border:1px solid #203056;border-radius:12px;overflow:hidden;
}
.video-card video{width:100%;height:180px;background:#000}
.video-card .meta{padding:10px 12px;color:var(--muted);font-size:.9rem}
.pdf-list{display:flex;flex-direction:column;gap:14px;margin-top:12px}
.pdf-item{
  border:1px solid #203056;border-radius:12px;overflow:hidden;background:#0c1326;
}
.pdf-item header{padding:10px 12px;font-weight:700;background:#0e1730}
.pdf-frame{
  width:100%;height:600px;border:0;background:#0a0a0a;display:block;
}
.pdf-viewer{
  background:#0b1228;border-top:1px solid #1b2545;
  display:flex;flex-direction:column;gap:10px;padding:12px;
}
.pdf-canvas{
  width:100%;height:auto;border-radius:10px;background:#10182e;
  box-shadow:0 8px 20px rgba(0,0,0,.25);
}
.pdf-controls{
  display:flex;align-items:center;justify-content:space-between;gap:12px;
}
.pdf-btn{
  padding:8px 12px;border-radius:10px;border:1px solid #2a3b68;
  background:#0e1730;color:#d6e6ff;font-weight:600;cursor:pointer;
}
.pdf-btn:disabled{
  opacity:.5;cursor:not-allowed;
}
.pdf-page{
  color:#9bb0d7;font-weight:700;
}
.note{color:#8599c5;font-size:.9rem}
.site-footer{padding:28px;color:#7e8fb6;text-align:center}
.site-footer a{color:var(--accent);text-decoration:none;font-weight:600}
.site-footer a:hover{text-decoration:underline}

/* discourage save/download */
iframe, video { user-select:none }
body { -webkit-user-select:none; -ms-user-select:none; }