cm mesurement css code example
Example 1: css em
em -> Relative to the font-size of the element
(2em means 2 times the size of the current font)
Example 2: pixels and em mdn
html {
font-size: 62.5%; /* font-size 1em = 10px on default browser settings */
}
span {
font-size: 1.6em;
}