How to cut 1 image into 9 smaller ones like a grid

Issue

I have one image on top of another and with a click on a grid tile it disappears and shows a part of the second image.

I have 2 images, one as a .main_container background and the other one I have in 3x3 grid.

The problem is that every tile in a grid is his own picture. I want one big picture to be cut and every piece be put in its own tile.

All JS I have is a click function that sets the opacity of a tile to 0. I can easily change the picture whenever I want without needing to edit the image into 9 pieces every time

enter image description here enter image description here

var clicks = 0;

$(".grid-item").click(function() {
  clicks++;
  console.log("clicked " + clicks);
  
  $(this).css({
    "opacity": "0"
  });
})

body {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  margin: 0;
}

.main_container {
  width: 60%;
  height: 60%;
  /* background-color: #3498db;  */
  background-image: url("/images/cat.jpg");
  background-size: cover;
  background-position: center;
  display: grid;
  grid-template-columns: auto auto auto;
}

.grid-item {
  background-image: url("/images/narava2_small.jpg");
  /* background-color: rgba(255, 255, 255, 0.8); */
  opacity: 1;
  border: 1px solid rgba(0, 0, 0, 0.8);
  padding: 20px;
  font-size: 30px;
  text-align: center;
  background-size: cover;
}

<div class="main_container">
  <div class="grid-item">1</div>
  <div class="grid-item">2</div>
  <div class="grid-item">3</div>
  <div class="grid-item">4</div>
  <div class="grid-item">5</div>
  <div class="grid-item">6</div>
  <div class="grid-item">7</div>
  <div class="grid-item">8</div>
  <div class="grid-item">9</div>
</div>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>

Solution

background-attachment: fixed would do the trick:

var clicks = 0;

$(".grid-item").click(function() {
  clicks++;
  //console.log("clicked " + clicks);
  
  $(this).css({
    "opacity": "0"
  });
})

body {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  margin: 0;
}

.main_container {
  width: 60%;
  background-image: url(https://picsum.photos/id/874/800/600);
  background-size: cover;
  background-position: center;
  display: grid;
  grid-template-columns: auto auto auto;
  border:solid 1px;
}

.grid-item {
  background-image: url(https://picsum.photos/id/871/800/600);
  background-size: 60% auto;
  background-position: center;
  background-attachment: fixed;
  opacity: 1;
  border: 1px solid rgba(0, 0, 0, 0.8);
  padding: 20px;
  font-size: 30px;
  text-align: center;
}

<div class="main_container">
  <div class="grid-item">1</div>
  <div class="grid-item">2</div>
  <div class="grid-item">3</div>
  <div class="grid-item">4</div>
  <div class="grid-item">5</div>
  <div class="grid-item">6</div>
  <div class="grid-item">7</div>
  <div class="grid-item">8</div>
  <div class="grid-item">9</div>
</div>

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>

Answered By - Kosh