What am I doing wrong

  width: 100%;
  height: 100vh;
  margin: 0;
  background-color: #f5f6f7;
  color: #1b1b32;
  font-family: sans-serif;
  font-size: 16px;
}

h1 , h2, h3, p{
  margin: 1em auto;
  text-align: center;
}

.center{
  margin: auto;
  padding: auto;
  display: block;
}
.img{
  height: auto;
  display: block;
  margin: 0 auto;
  max-width: 100%;
}
.image{ 
  display: block;
  max-width: 100%;
  height: auto;
  margin: 0 auto; 
}
 every time I run the test page it tells me that 
the img element should have a display of block which it has as far as i can see
be centered in the parent , have a max-width:100%; 
so what am i doing wrong.```

I would need to see the rest of your code, not just the css. What comes to mind without seeing your html is are you targeting the #img or .img, maybe your targeting a class or ID

i think u select it wrongly ,

<img></img>

is an element , so u need select it using

img{
}

instead of 

.img{

}

have tried that all to no avail still doesn’t work thanks for the help

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