make text responsive in css code example

Example 1: responsive text css

/* Uses vh and vm with calc */
@media screen and (min-width: 25em){
  html { font-size: calc( 16px + (24 - 16) * (100vw - 400px) / (800 - 400) ); }
}

/* Safari <8 and IE <11 */
@media screen and (min-width: 25em){
  html { font-size: calc( 16px + (24 - 16) * (100vw - 400px) / (800 - 400) ); }
}

@media screen and (min-width: 50em){
html { font-size: calc( 16px + (24 - 16) * (100vw - 400px) / (800 - 400) ); }
}

Example 2: responsive text

body {
  font-size: calc([minimum size] + ([maximum size] - [minimum size]) * ((100vw - [minimum viewport width]) / ([maximum viewport width] - [minimum viewport width])));
}