媒体查询中的PHP nth-child

Question

On MyPage are many pictures. In the normal case are 6 pictures in one row. If you change the size of the browser the number of pictures in each row will change. I solved this problem with media queries. In each row the last picture shouldnt get a margin-right: 5px;. But the nth-child wont change its every time the same, thats why the margin isnt correct. What did i wrong?

Here is my php output for the images:

<?php
    $sql = "SELECT * FROM bilder";
    $result=mysqli_query($db,$sql);
    while($row=mysqli_fetch_assoc($result)){
        echo "<img class='image' src='$row[bild_pfad]' alt='$row[bild_name]' style='$row[bild_werte]'>";
    } 
?>

Here is the css:

section{
    margin: 0px auto;
    width: 925px;
    margin-top: 55px;
}

.image{
    object-position: center; /* Center the image within the element */
    height: 150px;
    width: 150px;
    object-fit: cover;
    margin-right: 5px;
}

.image-margin{
    margin-right: 5px;
}

section img:nth-child(6n+6){
    margin-right:0;
}

@media only screen and (max-width : 924px) {
/* Five images in each row */
section{
    margin: 0px auto;
    width: 770px;
    margin-top: 55px;
}
  section img:nth-child(5n+5){
    margin-right:0;
  }
}

@media only screen and (max-width : 770px) {
  /* Four images in each row */
section{
    margin: 0px auto;
    width: 615px;
    margin-top: 55px;
}
  section img:nth-child(4n+4){
    margin-right:0;
  }
}

@media only screen and (max-width : 615px) {
section{
    margin: 0px auto;
    width: 460px;
    margin-top: 55px;
}
      section img:nth-child(3n+3){
    margin-right:0;
  }
}
@media only screen and (max-width : 460px) {
section{
    margin: 0px auto;
    width: 305px;
    margin-top: 55px;
}
      section img:nth-child(2n+2){
    margin-right:0;
  }
}

</div>

Answer 1

I solved my problem. I had to reset the old nth-child code like this:

section img:nth-child(6n+6){
    margin-right:0;
 }

@media only screen and (max-width : 924px) {
/* Five images in each row */
section{
    margin: 0px auto;
    width: 770px;
    margin-top: 55px;
}
  section img:nth-child(6n+6){
    margin-right:5px;
 }
  
  
  section img:nth-child(5n+5){
    margin-right:0;
  }
}

</div>