* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
} 

body, html { margin: 0; padding: 0; height: 100%; }
a-scene{
      width:100%;height:100%;position:absolute;top:0;left:0;z-index:0;
    }
    nav{
      position:fixed;top:1rem;left:1rem;max-width:260px;padding:0.8rem 1rem;
      background:rgba(0,0,0,0.55);color:#fff;font-family:sans-serif;
      font-size:0.95rem;line-height:1.4;border-radius:6px;z-index:10;
      box-shadow:0 2px 8px rgba(0,0,0,0.4);
    }
    nav a{color:#ffd966;text-decoration:none;}
    nav a:hover{text-decoration:underline;}
    body,html{margin:0;padding:0;overflow:hidden;}
p {
  color: white;
  margin-right: 15px;
  font-weight: bold;
  font-family: 'Gill Sans', 'Gill Sans MT', Calibri, 'Trebuchet MS', sans-serif;
}
 a-scene { width: 100%; height: 100%; }