*{box-sizing:border-box}html,body{height:100%;margin:0;padding:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Apple SD Gothic Neo,Noto Sans KR,sans-serif}
:root{--border:#e5e7eb;--muted:#6b7280;--primary:#2563eb}
.white{background:#ffffff;color:#111827}
.toolbar{position:sticky;top:0;z-index:20;display:flex;justify-content:space-between;align-items:center;gap:8px;padding:10px 14px;border-bottom:1px solid var(--border)}
.toolbar .group{display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.toolbar .group.small{font-size:12px}
.btn{appearance:none;border:1px solid var(--border);background:#fff;color:#111827;padding:8px 12px;border-radius:12px;cursor:pointer;font-size:14px}
.btn.primary{background:var(--primary);border-color:#1d4ed8;color:#fff}
.btn:active{transform:translateY(1px)}
.sidebar{position:fixed;left:0;top:56px;bottom:36px;width:300px;border-right:1px solid var(--border);padding:12px;overflow:auto}
.panel{background:#fff;border:1px solid var(--border);border-radius:12px;padding:12px;margin-bottom:12px}
.panel h3{margin:0 0 8px 0;font-size:15px}
.thumbs{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.thumbs .thumb{background:#fff;border:0;border-radius:10px;padding:6px;display:flex;flex-direction:column;gap:6px;align-items:center;justify-content:center;height:140px;cursor:grab}
.thumbs img{max-width:100%;max-height:240px;object-fit:contain;pointer-events:none}
.thumbs .cap{font-size:12px;color:#374151}
.hint{color:var(--muted);font-size:12px;margin-top:8px}
.hint.center{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);background:rgba(255,255,255,0.92);padding:8px 12px;border-radius:10px;border:1px solid var(--border)}
#stageWrapper{position:fixed;left:300px;right:0;top:56px;bottom:36px;background:#fff;display:flex;align-items:center;justify-content:center}
#stage{position:relative;width:100%;height:100%;border-radius:12px;border:1px solid var(--border)}
.statusbar{position:fixed;bottom:0;left:0;right:0;border-top:1px solid var(--border);padding:6px 10px;display:flex;justify-content:space-between;align-items:center;font-size:12px}
.muted{color:var(--muted)}
code{background:#f3f4f6;border:1px solid var(--border);padding:1px 4px;border-radius:6px}


/* === Mobile tweaks based on v5 (stacked layout) === */
@media (max-width: 768px){
  .toolbar{ position:sticky; top:0; z-index:30; }
  .toolbar .group{ gap:6px; overflow-x:auto; -webkit-overflow-scrolling:touch; }
  .sidebar{
    position:relative; left:auto; top:auto; bottom:auto;
    width:100%; height:auto; padding:10px;
    border-right:none; border-bottom:1px solid var(--border);
    overflow:visible;
  }
  #stageWrapper{
    position:relative; left:auto; right:auto; top:auto; bottom:auto;
    width:100%; height:62vh; background:#fff;
  }
  #stage{ width:100%; height:100%; }
  .thumbs{ grid-template-columns: repeat(3, 1fr); gap:6px; }
  .thumbs .thumb{ padding:4px; height:140px; }
  .thumbs img{ max-height:120px; }
}