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

:root {
  --panel: rgba(10, 14, 18, 0.72);
  --line: rgba(255, 255, 255, 0.12);
  --fg: #e8e4da;
  --dim: #9a958a;
  --accent: #e8b34b;
}

html, body { height: 100%; overflow: hidden; background: #06080b; }
body {
  font: 13px/1.45 -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--fg);
  user-select: none;
}

#gl { position: fixed; inset: 0; width: 100%; height: 100%; touch-action: none; }

/* ---------- loading overlay ---------- */
#overlay {
  position: fixed; inset: 0; z-index: 30;
  display: flex; align-items: center; justify-content: center;
  background: radial-gradient(ellipse at 50% 40%, #101820 0%, #05070a 75%);
  transition: opacity 0.6s;
}
#overlay.hidden { opacity: 0; pointer-events: none; }
.overlay-card { text-align: center; max-width: 400px; padding: 24px; }
.overlay-card h1 {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 44px; letter-spacing: 0.28em; font-weight: 400;
  color: var(--accent);
  text-shadow: 0 0 40px rgba(232, 179, 75, 0.35);
}
.overlay-card .sub { color: var(--dim); margin: 6px 0 26px; letter-spacing: 0.08em; }
.bar {
  height: 2px; background: rgba(255,255,255,0.1); border-radius: 2px; overflow: hidden;
}
#overlay-bar { height: 100%; width: 0%; background: var(--accent); transition: width 0.2s; }
#overlay-msg { margin-top: 12px; color: var(--dim); font-size: 12px; min-height: 1.2em; }

/* ---------- top bar ---------- */
#topbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 20;
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 18px;
  pointer-events: none;
}
#topbar .brand .title {
  font-family: Georgia, serif; font-size: 19px; letter-spacing: 0.22em; color: var(--fg);
  text-shadow: 0 1px 8px rgba(0,0,0,0.8);
}
#topbar .brand .tag { margin-left: 10px; color: var(--dim); font-size: 11px; letter-spacing: 0.1em; }
.hud {
  display: flex; gap: 14px; align-items: center;
  background: var(--panel); border: 1px solid var(--line); border-radius: 8px;
  padding: 6px 12px; backdrop-filter: blur(8px); pointer-events: auto;
  font-size: 11px; color: var(--dim);
}
.hud b { color: var(--fg); font-weight: 600; }
#btn-info {
  width: 22px; height: 22px; border-radius: 50%;
  background: transparent; border: 1px solid var(--line); color: var(--dim);
  cursor: pointer; font-size: 12px;
}
#btn-info:hover { color: var(--fg); border-color: var(--fg); }

/* ---------- control rail ---------- */
#controls {
  position: fixed; left: 14px; top: 50%; transform: translateY(-50%); z-index: 20;
  display: flex; flex-direction: column; gap: 14px;
  background: var(--panel); border: 1px solid var(--line); border-radius: 12px;
  padding: 14px; backdrop-filter: blur(10px);
  max-width: 168px;
}
.group { display: flex; flex-direction: column; gap: 5px; }
.group label {
  font-size: 10px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--dim);
  margin-bottom: 2px;
}
#controls button, #controls select {
  background: rgba(255,255,255,0.05); border: 1px solid var(--line); border-radius: 6px;
  color: var(--fg); padding: 6px 10px; font-size: 12px; cursor: pointer; text-align: left;
}
#controls button:hover { background: rgba(255,255,255,0.12); }
#controls button.on { border-color: var(--accent); color: var(--accent); background: rgba(232,179,75,0.08); }
.views { display: flex; gap: 4px; }
.views button { flex: 1; text-align: center; padding: 6px 0; }

/* ---------- hint + about ---------- */
#hint {
  position: fixed; bottom: 10px; left: 50%; transform: translateX(-50%); z-index: 20;
  color: var(--dim); font-size: 11px; letter-spacing: 0.05em;
  text-shadow: 0 1px 6px rgba(0,0,0,0.9);
  pointer-events: none;
}
#about {
  position: fixed; inset: 0; z-index: 40;
  display: flex; align-items: center; justify-content: center;
  background: rgba(3, 5, 8, 0.7); backdrop-filter: blur(4px);
}
#about.hidden { display: none; }
.about-card {
  position: relative; max-width: 560px; margin: 20px;
  background: #0d1218; border: 1px solid var(--line); border-radius: 14px;
  padding: 28px 30px;
  user-select: text;
}
.about-card h2 { font-family: Georgia, serif; font-weight: 400; margin-bottom: 12px; color: var(--accent); }
.about-card p { color: #c9c4b8; margin-bottom: 10px; font-size: 13.5px; }
.about-card b { color: var(--fg); }
#about-close {
  position: absolute; top: 10px; right: 14px;
  background: none; border: none; color: var(--dim); font-size: 22px; cursor: pointer;
}
#about-close:hover { color: var(--fg); }

@media (max-width: 760px) {
  #controls { left: 8px; bottom: 8px; top: auto; transform: none; flex-direction: row; max-width: none; right: 8px; overflow-x: auto; }
  #hint { display: none; }
}