searchform.php

<?php
/**
 * Template for displaying search forms
 *
 * @package WordPress
 * @subpackage quick-start
 * @since 1.0.0
 * @version 1.0.0
 */

/**
 * File Security Check.
 */
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

$unique_id = esc_attr( uniqid( 'search-form-' ) );

?>

<form role="search" method="get" class="search-form" action="<?php echo esc_url( home_url( '/' ) ); ?>">

    <label for="<?php echo $unique_id; ?>">
        <span class="screen-reader-text"><?php echo _x( 'Search for:', 'label', 'quick-start' ); ?></span>
    </label>

    <input type="search" id="<?php echo $unique_id; ?>" class="search-form__field"
           placeholder="<?php echo esc_attr_x( 'Search &hellip;', 'placeholder', 'quick-start' ); ?>"
           value="<?php echo get_search_query(); ?>" name="s"/>

    <button type="submit" class="button search-form__button"><?php echo _x( 'Search', 'search form submit button',
			'quick-start' ); ?></button>

</form>