body{font-optical-sizing:auto;color:#fff;background-color:#111;margin:0;font-family:Inter,sans-serif;overflow:hidden}#canvas-container{width:100vw;height:100vh;display:block}#ui-panel{-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px);pointer-events:auto;background:#1e1e1ed9;border-radius:12px;max-width:250px;padding:20px;position:absolute;top:20px;left:20px;box-shadow:0 4px 15px #00000080}h1{color:#fff;margin:0 0 15px;font-size:1.2rem}h2{color:#fff;margin:0 0 10px;font-size:1.1rem}.control-group{flex-direction:column;gap:8px;margin-bottom:15px;display:flex}button{color:#fff;cursor:pointer;background:#444;border:none;border-radius:6px;padding:10px 15px;font-size:.9rem;transition:background .2s,transform .1s}button:hover{background:#555}button:active{transform:scale(.98)}button.active-tool{background:#2196f3;font-weight:700}.btn-pos.active-tool{background:#e53935}.btn-neg.active-tool{background:#1e88e5}.btn-test.active-tool{color:#000;background:#ffb300}.divider{background:#555;height:1px;margin:15px 0}.btn-action{background:#4caf50;font-weight:700}.btn-action:hover{background:#45a049}#instructions{color:#bbb;margin-top:10px;font-size:.8rem;line-height:1.4}