JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>
<head>
<title>Page Title</title>
</head>
<body>
<tr>
<table>
 <td class='barorange' colspan='4'>PERTE EN dB</td>
 </tr>
 <tr>
 <td colspan='3' class='.inputwatt '>
 <div class='ui-input-text ui-body-inherit ui-corner-all'>
 <input style="text-align: right;" type="tel" id="outwatt1" size="auto" onblur="calcular();" />
 </div>
 </td>
 <td class='bargrise2' style='line-height:15px'>Watt <br><span style='font-size: 9.00pt;line-height:15px'> Sortie Répéteur</span></td>
 </tr>
 <tr>
 <td colspan='3' class='.inputwatt '>
 <div class='ui-input-text ui-body-inherit ui-corner-all'>
 <input style="text-align: right;" type="tel" id="outwatt2" size="auto" onblur="calcular();" />
 </div>
 </td>
 <td class='bargrise2' style='line-height:15px'>Watt<br><span style='font-size: 9.00pt;line-height:15px'>Sortie Filtration</span></td>
<tr>
  <td style='background-color:#A8D2DD;'>
 <span id="dbout"></span></td><td class='bargrise2' colspan='3'>PERTE EN "dB" ENTRE LES 2 SORTIES</td>

 </tr>
 </tr>
 </table>
 <script><!-- perte en dB-->	
function calcular() {
    var outwatt1 = Number(document.getElementById("outwatt1").value);
    var outwatt2 = Number(document.getElementById("outwatt2").value);
    var elemResult = document.getElementById("dbout");


    if (elemResult.textContent === undefined) {
       elemResult.textContent = String((Math.log10(outwatt1 / outwatt2)) * 10) + " dB";
    }
    else { // IE
       elemResult.innerText = String((Math.log10(outwatt1 / outwatt2)) * 10) + " dB";
	   
    }
}
</script>
</body>
</html>