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                <div class="bg1 pad1 dib">first div</div>
<div class="bg2 pad1 dib">second div</div>
<div class="bg3 pad1 dib">third div</div>


                .bg1 { background: lightgray }
.bg2 { background: lightslategray }
.bg3 { background: orange }
.pad1 { padding: 20px }
.pad2 { padding: 40px }
.m1 { margin: 20px }
.m2 { margin: 40px }
.dib { display: inline-block }

div { 
  position: static; 
  top: 40px 
div.bg2 { position: relative; }

1. The position CSS property's default value is "static" - and thus we don't have to specify it
2. When position is static, we cannot "move" elements out of the flow with the "top" property
3. When the value of position property is set to "relative", the top property works
4. How does a browser decide if it's going to use the position: static that is set in the div element CSS selector, or if it's going to use the position: relative that's set in the div.bg2 CSS selector? It resolves this conundrum with something that's called CSS specificity. We'll go back to this later.