What you can say about next code?
. card
{
position: relative;
left: -45px;
background-color: #0000AA;
width: 50px;
height: 50px;
}

Question

What you can say about next code? 
 . card 
 {  
 position: relative; 
 left: -45px; 
 background-color: #0000AA; 
 width: 50px; 
 height: 50px; 
 }

Answer

Used relative positioning.

Answer

Property left have a mistake (value < 0)

Answer

Created selector for all elements with class card

Answer

Current style don't usable for block elements

Answer

Created selector for all elements with id card

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