:root {
            --fps-excellent: #2ecc71;
            --fps-good: #f1c40f;
            --fps-poor: #e67e22;
            --fps-unplayable: #e74c3c;
        }
        .fps-panel {
            background: #f8fafc;
            border-radius: 1rem;
            padding: 1.25rem;
            box-shadow: 0 4px 12px rgba(0,0,0,0.05);
        }
        .fps-metric-card {
            text-align: center;
            background: white;
            border-radius: 0.75rem;
            padding: 0.75rem 0.5rem;
            box-shadow: 0 1px 3px rgba(0,0,0,0.1);
            transition: transform 0.1s ease;
        }
        .fps-value {
            font-size: 2.2rem;
            font-weight: 800;
            line-height: 1.2;
            font-family: 'Courier New', monospace;
        }
        .fps-label {
            font-size: 0.8rem;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: #4b5563;
        }
        canvas#fpsCanvas {
            display: block;
            width: 100%;
            background: #0a0f1e;
            border-radius: 12px;
            box-shadow: 0 8px 20px rgba(0,0,0,0.2);
            cursor: crosshair;
        }
        .control-slider {
            width: 100%;
            margin-top: 0.5rem;
        }
        .badge-fps {
            font-size: 0.85rem;
            padding: 0.3rem 0.7rem;
            border-radius: 40px;
        }
        .performance-note {
            background: #eef2ff;
            border-left: 5px solid #3b82f6;
        }
        .legend-fps {
            display: inline-block;
            width: 14px;
            height: 14px;
            border-radius: 3px;
            margin-right: 6px;
        }
        .authority-ref {
            font-size: 0.85rem;
            border-top: 1px solid #e2e8f0;
            margin-top: 1.2rem;
            padding-top: 1rem;
        }
        .btn-bench {
            transition: all 0.2s;
        }
        .glow-text {
            font-weight: 600;
        }
        @media (max-width: 768px) {
            .fps-value { font-size: 1.6rem; }
        }