CSS interno é: code example
Example: css interne
<head>
<style type="text/css">
p {color:white; font-size: 10px;}
.center {display: block; margin: 0 auto;}
#button-go, #button-back {border: solid 1px black;}
</style>
</head><head>
<style type="text/css">
p {color:white; font-size: 10px;}
.center {display: block; margin: 0 auto;}
#button-go, #button-back {border: solid 1px black;}
</style>
</head>