:root {
  color-scheme: dark;
  --bg-1: #06111f;
  --bg-2: #10294a;
  --panel: rgba(9, 18, 35, 0.76);
  --panel-border: rgba(255, 255, 255, 0.12);
  --text-main: #f5fbff;
  --text-dim: #b1c5db;
  --accent: #6ef3ff;
  --accent-2: #9dfcbe;
  --shadow: 0 26px 90px rgba(0,0,0,.38);
}
* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text-main);
  background: radial-gradient(circle at top, rgba(110,243,255,.18), transparent 28%), linear-gradient(180deg, var(--bg-2), var(--bg-1) 72%);
}
.app-shell { min-height: 100vh; display: grid; place-items: center; padding: 24px; }
.panel {
  width: min(100%, 560px);
  padding: 16px;
  border: 1px solid var(--panel-border);
  background: var(--panel);
  backdrop-filter: blur(18px);
  border-radius: 28px;
  box-shadow: var(--shadow);
}
.hud { display: flex; justify-content: space-between; gap: 12px; margin-bottom: 16px; padding: 0 8px; }
.label { margin: 0 0 4px; color: var(--text-dim); font-size: 13px; }
.value { margin: 0; font-size: 28px; font-weight: 800; }
.game-wrap { position: relative; overflow: hidden; border-radius: 24px; }
canvas { display: block; width: 100%; height: auto; background: linear-gradient(180deg, #08203d 0%, #103763 45%, #08162e 100%); }
.overlay {
  position: absolute; inset: 0; display: grid; place-items: center; padding: 24px;
  background: rgba(4, 10, 21, 0.48); transition: opacity 180ms ease;
}
.overlay.hidden { opacity: 0; pointer-events: none; }
.overlay.visible { opacity: 1; }
.card {
  width: min(100%, 340px); padding: 24px; border-radius: 24px;
  border: 1px solid rgba(255,255,255,.14); background: rgba(6, 14, 28, 0.74);
  backdrop-filter: blur(18px); text-align: center;
}
.eyebrow { margin: 0 0 8px; letter-spacing: .12em; text-transform: uppercase; color: var(--accent-2); font-size: 12px; font-weight: 700; }
h1,h2 { margin: 0 0 10px; }
.description,.hint { margin: 0; color: var(--text-dim); line-height: 1.6; }
.hint { margin-top: 14px; font-size: 13px; }
.actions { margin-top: 18px; }
.primary-btn {
  width: 100%; border: 0; border-radius: 999px; padding: 14px 18px; font-size: 16px; font-weight: 800;
  color: #03111f; background: linear-gradient(135deg, var(--accent), var(--accent-2)); cursor: pointer;
}
.primary-btn:hover { filter: brightness(1.03); }
@media (max-width: 640px) {
  .app-shell { padding: 12px; }
  .panel { padding: 12px; border-radius: 20px; }
  .hud { gap: 8px; }
  .value { font-size: 24px; }
  .card { padding: 20px; }
}