My background image not showing

I am struggling to get a background image to show. below is the code. Also I have already used a background image with the same path and it worked totally :confused: Any advice pleaseā€¦

  .pimg1{
    position: relative;
    opacity: 0.70;
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
    background-attachment: fixed;
  }
  .pimg1{
     background:url('../img/computer.jpeg');
 }

Thanks

<div class="pimg1">
      <div class="ptext">
      <span class="border">
        @MEDIA
        </span>
      </div>
    </div>

I never knew that. yes i will check, Thanks