The image/login screen is part of core, so you’ll make your life more difficult if you edit it, as you’ll need to do the same thing every time you upgrade and that’ll be a pain in the…
However, there is a plugin…
http://ww.wp.xz.cn/extend/plugins/custom-login/
You can also add two lines of code and a .css file to make the changes directly in your theme’s function.php file if you’re comfortable with that approach.
Here is the code to add to function.php:
<?php
function custom_login() {
echo '<link rel="stylesheet" type="text/css" href="' . get_settings('template_url') . 'custom-login.css" />';
}
add_action('login_head', 'custom_login');
?>
Then create custom-login.css in your theme directory and put this styling in it with your custom logo filename and its width and height:
h1 a {
background:url(custom_logo.jpg) no-repeat;
width:340px;
height:136px;
}
Upload your logo to the theme directory and you’re done.
