.immersive-hud{display:none}#fullscreen-btn{font-size:12px;min-height:44px}#fullscreen-hint{font-size:11px;line-height:1.5;color:#79634d;margin:8px 0 0}.board-stage{min-width:0;min-height:0}
body.immersive{overflow:hidden;overscroll-behavior:none;background:var(--bg)}
.immersive .shell{position:fixed;inset:0;max-width:none;width:100%;height:100dvh;padding:env(safe-area-inset-top,0px) max(12px,env(safe-area-inset-right,0px)) env(safe-area-inset-bottom,0px) max(12px,env(safe-area-inset-left,0px));display:flex;flex-direction:column;gap:0}
.immersive .topbar,.immersive .intro,.immersive .sidebar,.immersive .score-panel,.immersive .progress-panel,.immersive .mode-panel,.immersive .how-to,.immersive .small-quote,.immersive footer,.immersive .board-toolbar{display:none!important}
.immersive .immersive-hud{height:58px;flex:none;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);gap:8px}
.immersive-hud>div{font-size:11px;display:flex;gap:8px;align-items:baseline;white-space:nowrap}.immersive-hud strong{font-size:24px;color:var(--accent);font-variant-numeric:tabular-nums}.immersive-hud>div>span{font-size:9px;color:var(--muted)}.immersive-hud .icon-button{font-size:12px;min-height:44px;padding:8px 12px}
.immersive .game-layout{display:block;flex:1;min-height:0;min-width:0;padding:8px 0 0}
.immersive .play-column{height:100%;display:grid;grid-template-rows:24px minmax(0,1fr) 116px;gap:6px;min-height:0;min-width:0}
.immersive .game-top{height:auto}.immersive .board-stage{display:grid;place-items:center;overflow:hidden}.immersive .board-frame{width:var(--stage-size,100%);height:var(--stage-size,100%);max-width:none!important;max-height:100%;margin:0!important;aspect-ratio:1}
.immersive .touch-controls{display:flex;justify-content:center;align-items:center;gap:28px;margin:0!important;min-height:0}.immersive .touch-controls p,.immersive .touch-note{font-size:11px;color:var(--muted);line-height:1.8}.immersive .dpad{display:grid;grid-template-columns:60px 60px 60px;grid-template-rows:48px 48px;gap:6px}.immersive .dpad button{height:48px;min-height:44px;font-size:24px;border:1px solid #9d795335;border-radius:10px;background:#eae0d1;color:#5e4230;touch-action:none}.immersive .dpad button:active{background:#e4af87}.immersive .dpad .up{grid-column:2;grid-row:1}.immersive .dpad .left{grid-column:1;grid-row:2}.immersive .dpad .down{grid-column:2;grid-row:2}.immersive .dpad .right{grid-column:3;grid-row:2}
.immersive #fullscreen-hint{flex:none;text-align:center;margin:0;padding:4px 8px;font-size:10px}.immersive .overlay-content{padding:12px}.immersive .overlay-mark{margin-bottom:12px}.immersive .overlay h2{font-size:24px}.immersive .overlay p:not(.eyebrow){margin-bottom:14px}.immersive .overlay-tip{margin-top:10px}
@media(max-width:480px){.topbar{gap:10px}.brand{font-size:16px}.brand-en{font-size:7px}.icon-button{padding:8px 10px}.immersive .touch-note{display:none}.immersive .touch-controls{gap:18px}.immersive .snake-mark{display:none}.immersive .overlay .eyebrow{display:none}.immersive .overlay-tip{display:none}}
@media(orientation:landscape) and (max-height:600px){.immersive .immersive-hud{height:48px}.immersive .game-layout{padding-top:4px}.immersive .play-column{grid-template-columns:minmax(0,1fr) 204px;grid-template-rows:20px minmax(0,1fr);gap:4px 12px}.immersive .game-top{grid-column:1/-1}.immersive .board-stage{grid-column:1;grid-row:2}.immersive .touch-controls{grid-column:2;grid-row:2;flex-direction:column;gap:12px}.immersive .touch-note{display:none}.immersive .touch-controls p{margin:0;text-align:center}.immersive .snake-mark,.immersive .overlay .eyebrow,.immersive .overlay-tip{display:none}.immersive .result{margin:0 0 8px}.immersive .result strong{font-size:36px}.immersive .overlay h2{font-size:20px;margin-bottom:8px}.immersive .overlay p:not(.eyebrow){font-size:10px;margin-bottom:10px}.immersive .text-button{margin-top:0;min-height:36px}}
@media(max-width:360px){.immersive-hud .icon-button{font-size:11px;padding:8px}.immersive-hud>div>span{display:none}.immersive .touch-controls p{display:none}}