Code for footer.php

<?php
$about_us = "<div class="about-link"><a href="domain/about_us.php">About Us</a></div>"
$follow_me = "<div class="follow-me"><a href="domain/follow_me.php">Follow Me</a></div>"
?>

Code for main.php

<?php
include 'domain/footer.php'

echo "$about_us and $follow_me"
?>

.about-link, .follow-me { display: inline-block; }

.about-link, .follow-me {float:left;}

.about-link, .follow-me {
 display: inline-block !important;
}

<div class="about-link ftr"><a href="domain/about_us.php">About Us</a></div>
<div class="follow-me ftr"><a href="domain/follow_me.php">Follow Me</a></div>

echo "$about_us and $follow_me"

echo "$about_us $follow_me"

about-link, .follow-me {
  display: inline-block;
}