PHP code not applying CSS stylesheet

Question

So my CSS/PHP/HTML situation is pretty messed up. Basically something works with one php script but not another.

My code is as follows (just part of it):

<?php
         if ($daten->getData_DB_User($get_page_num) != false) {
         ?>
            <div class="seiten_vor_zur">
            <br>
                <td> <div class="seitenanzahl">
                          <button disabled>Seite : <?php echo $get_page_num ?></button>
                    </div>
                </td>
                <td>
                    <a href="<?php echo $_SERVER['PHP_SELF'] . "?q=lesen&seite=" . $get_last_page; ?>"
                           role="button">Vorherige Seite
                    </a>
                </td> &nbsp;
                <td>
                    <a href="<?php echo $_SERVER['PHP_SELF'] . "?q=lesen&seite=" . $get_next_page; ?>"
                           role="button">Nächste Seite
                    </a>
                </td>
            <?php
            }
            else{
                echo "Es gibt keine weiteren Einträge.<p> <a 
    href='javascript:window.history.back()'>Zurück</a> </p>";
            }
            ?>
            </div>

Now my problem is that I'm trying to style the last p and element in a div box class="seiten_vor_zur". My page doesn't use CSS entries, I'd like to know why?

This is the CSS entry:

.seiten_vor_zur{
    
        text-align: center;
    
    }
    .seiten_vor_zur a{
        text-decoration: none;
        border-radius: 50%;
        text-shadow: 1px 1px 2px #05128f, 0 0 25px #ffffff, 0 0 5px #ffffff;
    
    }

    .seiten_vor_zur a:visited {
        text-decoration: none;
        color: #05128f;
    }
    .seiten_vor_zur a:hover {
        background-color: rgba(6, 161, 227, 0.4);
    }

Answer 1

I don't see any css files linked to your php files. Add your css file to your php file and see if it loads

Or use inline CSS just to see it work first.