:root { color-scheme: dark; }

* { box-sizing: border-box; touch-action: manipulation; }

html, body {
  margin: 0; padding: 0; height: 100dvh; overflow: hidden;
  background: #0a0a0a; color: #f5f5f5;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Apple SD Gothic Neo", "Noto Sans KR", sans-serif;
  -webkit-font-smoothing: antialiased; -webkit-tap-highlight-color: transparent;
  user-select: none; -webkit-user-select: none; overscroll-behavior: none;
}
main {
  height: 100%; max-width: 480px; margin: 0 auto;
  display: flex; flex-direction: column;
  padding: max(60px, env(safe-area-inset-top)) 14px max(16px, env(safe-area-inset-bottom));
  gap: 9px;
}
.score-bar { display: flex; gap: 7px; align-items: stretch; }
.score-box { flex: 1; background: #161616; border: 1px solid #2a2a2a; border-radius: 12px; padding: 6px 8px; text-align: center; min-width: 0; }
.score-label { display: block; font-size: 10px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: #a0a0a0; white-space: nowrap; }
.moves-val, .solved-val, .best-val { display: block; font-size: 20px; font-weight: 800; font-variant-numeric: tabular-nums; color: #f5f5f5; margin-top: 1px; line-height: 1.1; }
.bar-btn { flex: 0 0 auto; font: inherit; color: #fff; border: none; border-radius: 12px; padding: 0 13px; min-height: 50px; cursor: pointer; font-weight: 700; font-size: 13px; -webkit-tap-highlight-color: transparent; }
.reset-btn { background: #2f3742; } .reset-btn:active { background: #3a434f; }
.new-btn { background: #4f9eff; } .new-btn:active { background: #3d8ae8; }

/* target preview */
.target { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.target-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: #9aa0aa; }
.target-grid { display: grid; gap: 3px; }
.tcell { width: 22px; height: 22px; border-radius: 5px; background: transparent; display: flex; align-items: center; justify-content: center; font-size: 12px; font-weight: 800; }
.tcell.tatom { box-shadow: inset 0 -2px 3px rgba(0,0,0,0.28); }

.message { margin: 0; text-align: center; font-size: 12.5px; color: #a0a0a0; letter-spacing: 0.02em; min-height: 16px; }

/* board */
.board {
  flex: 0 1 auto; width: 100%; max-width: 392px; margin: 0 auto; aspect-ratio: 1 / 1;
  display: grid; gap: 3px; background: #2a2622; border: 3px solid #1c1916; border-radius: 10px; padding: 3px;
}
.cell { position: relative; border-radius: 5px; display: flex; align-items: center; justify-content: center; }
.cell.floor { background: #cdbd9c; }
.cell.wall  { background: #5a4a38; box-shadow: inset 0 0 0 1px #4a3c2c, inset 0 -3px 4px rgba(0,0,0,0.35); }
.cell.move { cursor: pointer; }
.cell.move::after { content:''; position:absolute; inset: 14%; border-radius: 50%; background: rgba(70,150,90,0.25); box-shadow: inset 0 0 0 2px rgba(80,200,120,0.7); }
.cell.move:active { background: #b7e0c2; }
.arrow { position: relative; z-index: 1; font-size: 20px; font-weight: 800; color: #2c6b3f; line-height: 1; }

.atom {
  width: 84%; height: 84%; border-radius: 50%; cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  font-size: 17px; font-weight: 800; letter-spacing: -0.02em;
  box-shadow: 0 2px 3px rgba(0,0,0,0.4), inset 0 -2px 3px rgba(0,0,0,0.22);
}
.atom.sel { box-shadow: 0 0 0 3px #ffd23f, 0 2px 4px rgba(0,0,0,0.5); }

/* chrome */
.home-link, .hof-link {
  position: fixed; top: max(12px, env(safe-area-inset-top)); z-index: 10;
  width: 40px; height: 40px; display: inline-flex; align-items: center; justify-content: center;
  border-radius: 999px; background: rgba(0,0,0,0.35); color: #fff; text-decoration: none;
  font-size: 20px; font-weight: 600; line-height: 1; border: none; cursor: pointer; font-family: inherit;
  -webkit-tap-highlight-color: transparent; backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px);
}
.home-link { left: max(12px, env(safe-area-inset-left)); }
.hof-link { right: max(12px, env(safe-area-inset-right)); }
@media (hover: hover) { .home-link:hover, .hof-link:hover { background: rgba(0,0,0,0.55); } }

/* overlay */
.overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.55); display: flex; align-items: center; justify-content: center; z-index: 20; padding: 20px; backdrop-filter: blur(2px); -webkit-backdrop-filter: blur(2px); }
.overlay[hidden] { display: none; }
.overlay-card { background: #161616; border: 1px solid #2a2a2a; border-radius: 18px; padding: 24px 22px; display: flex; flex-direction: column; gap: 12px; align-items: center; text-align: center; min-width: 240px; max-width: 320px; width: 100%; }
.overlay-card h2 { margin: 0; font-size: 22px; font-weight: 800; letter-spacing: -0.02em; }
.overlay-score { margin: 0; font-size: 56px; font-weight: 800; font-variant-numeric: tabular-nums; letter-spacing: -0.04em; line-height: 1; }
.overlay-score .unit { font-size: 18px; font-weight: 600; color: #c0c0c0; margin-left: 6px; letter-spacing: 0; text-transform: uppercase; }
.overlay-card button { font: inherit; color: #fff; background: rgba(255,255,255,0.10); border: 1px solid rgba(255,255,255,0.22); border-radius: 999px; padding: 12px 20px; min-height: 44px; cursor: pointer; font-weight: 600; font-size: 14px; width: 100%; -webkit-tap-highlight-color: transparent; }
.overlay-card button:active { background: rgba(255,255,255,0.18); }
.overlay-card .save-btn, .overlay-card .next-overlay-btn { background: #4f9eff; border-color: #4f9eff; }
.overlay-card .save-btn:active, .overlay-card .next-overlay-btn:active { background: #3d8ae8; }