Script para mostrar width, height y pixel ratio para una media querie

Dimensiones del viewport

<p id="size"></p>
<p id="ratio"></p>

<script>
    function updateSize() {
        let width = window.innerWidth;
        let height = window.innerHeight;
        let dpr = window.devicePixelRatio;

        document.getElementById("size").innerText = `Viewport: ${width} × ${height}px`;
        document.getElementById("ratio").innerText = `Pixel Ratio: ${dpr}`;
    }

    window.addEventListener("resize", updateSize);
    updateSize();
</script>