问如何使用html或css在wordpress中设计php页面主题模板？

EN

        <?php
        /*
        Template Name: isbn 
        */
        ?>

        <form action="" method="post" name="myForm">
        Filter <input id="isbn" type="text" name="isbn" />
        <input type="submit" name="submit" value="Submit" /></form>

        <?php get_header(); ?>
        <?php 
        if(isset($_POST['submit']))
        {
        global $wpdb;
         $table_name = "isbn";  // change this to your table name
         $field = $_POST['isbn']; // change this to your isbn field $_POST['ISBN'];
        $retrieve_data = $wpdb->get_results( "SELECT * FROM $table_name where isbn = '".$field."'");
        foreach ($retrieve_data as $retrieved_data) {

        echo $retrieved_data->title; 
        // echo $retrieved_data->image;  // for image
         }
        }
       ?>