shmatuan

<input type="text" id="login"> 
<script>
  var input = document.getElementById("login")
  var data = {
    "login":"",
    "password":""
  }
  input.oninput = function() {
    data.login = input.value;
  };
</script>

<table>
    <tr> 
     <td rowspan="2" bgcolor="#FBF0DB">Ячейка 1</td>
     <td>Ячейка 2</td>
    </tr>
    <tr> 
     <td>Ячейка 3</td>
    </tr>
   </table>

#particles-js {
flex: 0;
/*или сделать его position: absolute;*/
}
.profile {
width: 100%;
flex: 1;
}

var pics = {
    "one": "https://image.freepik.com/free-photo/cute-cat-picture_1122-449.jpg",
    "two": "https://media.wired.com/photos/598e35fb99d76447c4eb1f28/master/pass/phonepicutres-TA.jpg",
    "three": "https://c1.staticflickr.com/2/1520/24330829813_944c817720_b.jpg"    
  }
function check_value(event){
   document.getElementById("imagetest").src = pics[event.target.value] ;
}

$('#goToNextSlide').click(function(){
        slider.pause();    
    });

<div class="abou__item">
  <span>about</span>
  <img src="img/about2.jpg" alt="">
  <span style="opacity: 0;">about</span>
</div>

.header{
  min-width: fit-content;
  max-width: 100%;
}

.grid{
  display: flex;
  flex-wrap :wrap;