Owlpixel

This plugin comes with a lot of feature specially for login page of wordpress. 
Custom background for login page, Custom background for login form, Change all the color of login page. All of this can be done with this plugin. 
Admin login page customization never being easy without this plugin. 
You can change admin page background, login page background, custom logo etc. 
You can see your login page by adding slug “wp-login” or “wp-admin” after your domain…
All can be done with this –>
<pre><code>* Upload custom logo to admin page
* Customize background image of admin page area
* Customize background image of admin login form area
* Change background color of login page
* Change background color of login form
* Change color of label for fields
* Change color of nav link bottom of form
* Change the color of submit button
* Change the color of submit button text
* Add custom css
* More are coming soon...
</code></pre>
<h3>Video Tutorial</h3>
<iframe loading="lazy" class="youtube-player" width="750" height="422" src="https://www.youtube.com/embed/Ri_d1OmnbfU?version=3&rel=1&showsearch=0&showinfo=1&iv_load_policy=1&fs=1&hl=en-US&autohide=2&wmode=transparent" allowfullscreen="true" style="border:0;" sandbox="allow-scripts allow-same-origin allow-popups allow-presentation allow-popups-to-escape-sandbox"></iframe>

Custom login page

Custom login page Customizer, Add custom logo,Custom background and more.

Astahub

Haris

A fine designed and unique WordPress login page style that includes some customizations, also comes with login theme selector. Yaaaay!
Features :
<ul>
<li>Nice and well designed login style</li>
<li>Responsive design</li>
<li>Customizable login title</li>
<li>Customizable login logo</li>
<li>Customizable login message</li>
<li>Comes with 4 awesome login themes</li>
</ul>
Usage Instruction :
<ol>
<li>Install the plugin</li>
<li>Open the settings page on Appearance -> Login Screen</li>
<li>Change the plugin options then save it</li>
</ol>

Custom Login Screen

An unique and customizable WordPress login screen.

Custom login page vs Custom Login Screen