Check out example codes for "css change text". It will help you in understanding the concepts better.

Code Example 1

#search {
    width: 20em;  height: 2em;
}

Code Example 2

IDENTIFIER {
	visibility: hidden;
	position: relative;
}
IDENTIFIER::after {
	visibility: visible;
	position: absolute;
	top: 0;
	left: 0;
	content: "NEW_CONTENT";
}

Code Example 3

p{
	color: White;
}

Code Example 4

h1 {  
  color: green;
}

Code Example 5

color:#ffffff;

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