.tool-shell { display: grid; gap: 14px; }
.card { background: rgba(255,255,255,0.92); border-radius: 12px; padding: 14px; box-shadow: 0 2px 10px rgba(0,0,0,.08); }
.tool-head h1 { font-size: 24px; margin-bottom: 6px; }
.tool-head p { color: #334155; font-size: 14px; }
.tool-actions { margin-bottom: 10px; }
.btn-link { display:inline-block; background:#111827; color:#fff; text-decoration:none; padding:8px 12px; border-radius:8px; }
.hint { color:#64748b; margin-bottom:8px; font-size:12px; }
button { border:none; border-radius:8px; padding:8px 12px; background:#111827; color:#fff; cursor:pointer; }
.channel-grid, .calc-grid { display:grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap:10px; margin:10px 0; }
.channel-grid label, .calc-grid label { background:#f8fafc; border:1px solid #e2e8f0; border-radius:8px; padding:8px; font-size:12px; display:flex; flex-direction:column; gap:6px; }
#rgbaCanvas, #hdrCanvas { width:100%; max-height:420px; object-fit:contain; background:#0b1120; border-radius:10px; margin-top:10px; }
.tool-iframe { width:100%; height:70vh; border:1px solid #e2e8f0; border-radius:10px; }
.result-box { background:#0f172a; color:#e2e8f0; border-radius:8px; padding:10px; min-height:80px; }
.workbench-toolbar { display:flex; flex-wrap:wrap; gap:8px; margin-bottom:10px; }
.workbench-toolbar button, .workbench-toolbar label { border:none; border-radius:8px; padding:8px 10px; background:#37b18c; color:#fff; cursor:pointer; font-size:13px; }
.workbench-toolbar .secondary { background:#6b7280; }
.workbench-toolbar .danger { background:#ef4444; }
.workbench-toolbar input[type="file"] { display:none; }
.workbench-textarea { width:100%; min-height:180px; border:1px solid #d1d5db; border-radius:8px; padding:10px; box-sizing:border-box; resize:vertical; font-size:13px; }
.snippet { border:1px solid #e5e7eb; border-radius:10px; background:#f8fafc; padding:10px; margin-top:8px; }
.snippet pre { white-space:pre-wrap; margin:8px 0; font-size:12px; }
@media (max-width: 1200px) { .channel-grid, .calc-grid { grid-template-columns: 1fr; } }