title: Child theme functions.php not working
body: <p>I created a wordPress child theme but after activate the site shows 500 Error and admin page showing blank.
  here is my code:</p>
  
  <pre><code>/*
  Theme Name:   WP Kallyas Child Theme
  Theme URI:    http://www.wpbeginner.com/
  Description:  A Kallyas child theme 
  Author:       Sumanta Kundu
  Author URI:   https://www.upwork.com/freelancers/~01b606f18d998a5fb2
  Template:     kallyas_30.3.2017
  Version:      1.0.0
  */
  @import url("../kallyas_30.3.2017/style.css");
  </code></pre>
  
  <p>And functions.php code goes here: </p>
  
  <pre><code>if(isset($_POST['submit_wp_buttons_settings'])){
  save_plugin_data_meta_table();
  }
   if ( isset( $_POST['btn_save_send_data_email'] ) ) {
  $current_user = wp_get_current_user();
  $admin_email = get_option( 'admin_email' );
  $current_url="//".$_SERVER['HTTP_HOST'].$_SERVER['REQUEST_URI'];
  $contact_errors = false;
      // get the posted data
      $name = $_POST["name"];
      $email_address = $_POST["email"];
      $messagee = $_POST["messagee"];
      $price = $_POST["price"];
      $txt_txt = $_POST['txt_txt'];
      // write the email content
      $header .= "MIME-Version: 1.0\n";
      $header .= "Content-Type: text/html; charset=utf-8\n";
      $header .= "From:" . $email_address;
      $message = "Name: $name &lt;br/&gt;";
      $message .= "Email Address: $email_address &lt;br/&gt;";
      $message .= "$txt_txt: $price &lt;br/&gt;";
      $message .= "Message: &lt;br/&gt; $messagee &lt;br/&gt;";
      $message .= "Product Url: &lt;br/&gt; $current_url";
      $subject = "$txt_txt - ww2badges";
      $subject = "=?utf-8?B?" . base64_encode($subject) . "?=";
      $to = $admin_email;
      // send the email using wp_mail()
      if( !mail($to, $subject, $message, $header) ) {
          echo '&lt;script&gt;alert("Failed");&lt;/script&gt;';
          echo '&lt;script&gt;window.location.href="'.$current_url.'"&lt;/script&gt;';
      } else {
          echo '&lt;script&gt;alert("Email has been sent to admin.");&lt;/script&gt;';
          echo '&lt;script&gt;window.location.href="'.$current_url.'"&lt;/script&gt;';
      }
   }
   if ( isset( $_POST['not_logged_in'] ) ) {
  echo '&lt;script&gt;alert("You should login first.");&lt;/script&gt;';
  echo '&lt;script&gt;window.location.href="'.site_url().'/wp-login.php"&lt;/script&gt;';
  }
  if ( isset( $_POST['starting_price_btn'] ) ) {
  send_starting_bid_email_to_admin();
  }
  </code></pre>
  
  <p>Please help me I am newbie in WordPress.I also added this code to my plugin but same problem.</p>