Check out example codes for "css especifico para safari". It will help you in understanding the concepts better.

Code Example 1

@media not all and (min-resolution:.001dpcm) { 
     @supports (-webkit-appearance:none) {
          ...
     }
}

Code Example 2

/* Safari 7.1+ */

_::-webkit-full-page-media, _:future, :root .safari_only {

  color:#0000FF; 
  background-color:#CCCCCC; 

}

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