It is placed after <body>:
Code
<script type="text/javascript">
function age(a){
if (!a){return '';}
// Get Current Date
var now = new Date();
var y = now.getYear();
var m = now.getMonth()+1;
var d = now.getDate();
if (!y){return '';}
// Split User's Birthday
aa=a.match(/^([0-9]+)-([0-9]+)-([0-9]+)/);
if (!aa[1]){return '';}
// Get User's Age
var age = y-aa[1];
if (m==aa[2] && d<aa[3]){age--;}
else if (m<aa[2]){age--;}
return age;
}
</script>
Put this anywhere on the page where needed ! :
Code
<script type="text/javascript">
if(age('$USER_BIRTHDAY$')>=18) {
document.write('<P>I Confirm that: <BR>
document.write('<P>- I am 18 years or more, and I go to these pages with a full understanding of what is possible they may contain materials that are targeted only at the adult audience ; <BR></P>');
document.write('<P>- material that I am viewing is only for my personal use and I will not show them to persons under 18 years;');
document.write('<P>- I , as an adult and able-bodied citizen , have an inalienable right to read or watch any kind of material that I choose, and argue that the pages of this kind do not contain offensive or unacceptable to me material, and not be interpreted by me afterwards as abusive or unacceptable;<BR></P>');
document.write('<P>- viewing, reading and swapping over the network materials contained on the pages of this kind do not violate the laws of my locality ( country , city, region , etc. );<BR></P>');
document.write('<P>- I am solely responsible for the consequences of my viewing, reading , using or transporting the network the material contained on these pages are not going to carry this responsibility on any other legal or natural person .</P>');
document.write('<br>');
document.write('<p align="center"><a href="ссылка">I Don't Agree</a><br>');
document.write('<br>');
document.write('<p align="center"><a href="ссылка">I Agree</a><br>');
}
else {
document.write('You are too young to view this page <br>');
}
</script>