User:Funest/monobook.js

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var logo = document.getElementById("p-logo");
var number = Math.floor((Math.random() * 3) + 1);
function change() {
if (number == 1) {
  document.getElementById("p-logo").style.background-image = "url(https://lh4.googleusercontent.com/-ziwpYa3MhLU/U8gKZ1CHPaI/AAAAAAAAARg/eje3jKlJqZg/w161-h152-no/Wiki+Logo+KHHD25+%2528ver4%2529.png) !important";
} else if (number == 2) {
  document.getElementById("p-logo").style.background-image = "url(https://lh4.googleusercontent.com/-snvUTQQeGAs/U8gEuySFFwI/AAAAAAAAAQo/v1FW5QLSnlM/w161-h152-no/Wiki+Logo+KHHD25+%2528ver2%2529.png) !important";
} else if (number == 3) {
  document.getElementById("p-logo").style.background-image = "url(https://lh4.googleusercontent.com/-TYRJvBBdLlo/U8gItOAyNjI/AAAAAAAAARA/y2FlZ1SDf2I/w161-h152-no/Wiki+Logo+KHHD25+%2528ver3%2529.png) !important"
}
};
window.onload=change();