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HTML

CSS

CSS Base

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JavaScript

Babel includes JSX processing.

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HTML

              
                <body>
  
<p>Soy un párrafo que tengo font-size:1em, por lo tanto, el tamaño de mi fuente es igual al de mi padre, en este caso el body: 20px </p>

<div>
  <p>Soy un párrafo que está dentro de un div tengo font-size:1em, por lo tanto, el tamaño de mi fuente es igual al de mi padre, en este caso el div: 25px </p>
</div>

<p class="ejemplo">Soy un párrafo de la clase ejemplo con font-size:1rem, da igual que esté dentro o fuera de un div, al ser 1rem mi tamaño será el tamaño predeterminado para el elemento raiz, en este caso 16px</p>

<p class="ejemplo2">Soy un párrafo de la clase ejemplo2 con font-size:30px, da igual que esté dentro o fuera de un div, tengo un tamaño fijo de 30px</p>
  
</body>





              
            
!

CSS

              
                body{
  font-size:20px;
}

div{
  font-size:25px;
}

p {
  font-size:1em;
}

div p {
  font-size:1em;
}

p.ejemplo {
  font-size:1rem;
}

p.ejemplo2 {
  font-size:30px;
}

              
            
!

JS

              
                
              
            
!
999px

Console