JSFiddle - React, Tailwind, and code Playground

HTML

<div id="banderole">
<span id="displayDate" class="date"></span>
<span id="displayHeure" class="heure"></span>
<h1 class="titre">VIDEO SURVEILLANCE</h1> 
</div>

CSS

#banderole {
background-color:black;
min-width:720px;
}
#banderole .heure {
color:rgb(0,0,255);
font-size:32px;
float:left;
margin-left: 10;
}
#banderole .date {
color:rgb(0,0,255);
font-size:32px;
float:right;
margin-right: 10;
}
#banderole .titre {
color:rgb(255,255,255);
text-align:center;
}

JavaScript

function displayHorloge() {  
  document.getElementById('displayDate').innerHTML = (new Date).toLocaleDateString();
  document.getElementById('displayHeure').innerHTML = (new Date).toLocaleTimeString();
  setTimeout(displayHorloge,1000);
}

displayHorloge();