html, body {
  margin: 0;
  height: 100%;
  width: 100%;
  background: #000;
  /*overflow: hidden;*/
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: monospace;
}
#wrap { position: relative; line-height: 0; }
canvas { display: block; }

#toggleBtn {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 10;
  background: rgba(15, 15, 15, 0.85);
  color: #bbb;
  border: 1px solid #333;
  padding: 6px 10px;
  font-family: monospace;
  font-size: 12px;
  cursor: pointer;
  border-radius: 3px;
  user-select: none;
}
#toggleBtn:hover { background: rgba(35, 35, 35, 0.9); color: #eee; }

#internalsBtn {
  position: absolute;
  top: 10px;
  left: 96px;
  z-index: 10;
  background: rgba(15, 15, 15, 0.85);
  color: #bbb;
  border: 1px solid #333;
  padding: 6px 10px;
  font-family: monospace;
  font-size: 12px;
  cursor: pointer;
  border-radius: 3px;
  user-select: none;
}
#internalsBtn:hover { background: rgba(35, 35, 35, 0.9); color: #eee; }
#internalsBtn.active { background: rgba(122, 168, 168, 0.35); color: #eaf6f6; border-color: #7aa8a8; }

#panel {
  position: absolute;
  top: 46px;
  left: 10px;
  z-index: 9;
  background: rgba(15, 15, 15, 0.9);
  border: 1px solid #333;
  border-radius: 4px;
  padding: 14px 16px;
  width: 200px;
  color: #ccc;
  font-family: monospace;
  font-size: 12px;
  transition: opacity 0.15s ease, transform 0.15s ease;
}
#panel.hidden {
  opacity: 0;
  transform: translateY(-6px);
  pointer-events: none;
}
#panel .row { margin-bottom: 14px; }
#panel .row:last-child { margin-bottom: 0; }
#panel label {
  display: flex;
  justify-content: space-between;
  margin-bottom: 5px;
  color: #999;
}
#panel label .val { color: #ddd; }
#panel input[type=range] { width: 100%; accent-color: #7aa8a8; }
#panel button {
  width: 100%;
  margin-top: 4px;
  background: rgba(40, 40, 40, 0.9);
  color: #ccc;
  border: 1px solid #333;
  padding: 6px 10px;
  font-family: monospace;
  font-size: 11px;
  cursor: pointer;
  border-radius: 3px;
}
#panel button:hover { background: rgba(60, 60, 60, 0.9); color: #eee; }

#info {
  position: absolute;
  bottom: 8px;
  left: 10px;
  z-index: 8;
  font-size: 11px;
  color: #888;
  background: rgba(15, 15, 15, 0.6);
  padding: 4px 8px;
  border-radius: 3px;
  letter-spacing: 0.02em;
}

/* ---- evolutionary selector (evolve.html) ---- */
body { flex-direction: column; justify-content: flex-start; }
#bar {
  width: 100%;
  box-sizing: border-box;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  background: rgba(15, 15, 15, 0.92);
  border-bottom: 1px solid #333;
  color: #ccc;
  font-size: 12px;
  flex-wrap: wrap;
  z-index: 20;
}
#bar .title { color: #ddd; font-weight: bold; margin-right: 6px; }
#bar label { display: flex; align-items: center; gap: 4px; color: #999; }
#bar input[type=number] {
  width: 52px; background: #111; color: #ddd; border: 1px solid #333;
  border-radius: 3px; padding: 3px 5px; font-family: monospace; font-size: 11px;
}
#bar button {
  background: rgba(40, 40, 40, 0.9); color: #ccc; border: 1px solid #333;
  padding: 6px 10px; font-family: monospace; font-size: 11px; cursor: pointer;
  border-radius: 3px;
}
#bar button:hover { background: rgba(60, 60, 60, 0.9); color: #eee; }
#bar .stat { color: #888; }
#bar .stat b { color: #ddd; }
/* slider control blocks in the bar */
#bar .ctl {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 84px;
}
#bar .ctl label {
  display: flex;
  justify-content: space-between;
  font-size: 10px;
  color: #999;
}
#bar .ctl label .val { color: #ddd; }
#bar .ctl input[type=range] {
  width: 100%;
  accent-color: #7aa8a8;
  cursor: pointer;
}

#pop {
  flex: 1;
  width: 100%;
  box-sizing: border-box;
  display: grid;
  gap: 6px;
  padding: 8px;
  align-content: start;
}
#pop .panel {
  position: relative;
  border: 2px solid #222;
  border-radius: 4px;
  overflow: hidden;
  cursor: pointer;
  background: #000;
  line-height: 0;
}
#pop .panel canvas { width: 100%; height: 100%; display: block; }
#pop .panel.selected { border-color: #7aa8a8; box-shadow: 0 0 8px rgba(122, 168, 168, 0.6); }
#pop .panel::after {
  content: '✓';
  position: absolute; top: 4px; right: 6px;
  color: #7aa8a8; font-weight: bold; opacity: 0;
  text-shadow: 0 0 3px #000;
}
#pop .panel.selected::after { opacity: 1; }

/* Styles for subsystem interactions view */
#visualization { background: #f0f8ff; padding: 20px; border-radius: 8px; }