获取var的长度并创建宽度

我有一个复杂的横幅背景和文本融入其中，所以我需要添加一个背景这个div，所以它显示给定的文本。是否有一种方法使用PHP，我可以得到文本的长度，并把它变成一个px，所以我可以用它来设置div的宽度?

我想让entry-title自动运行

<div class="fusion-page-title-bar fusion-page-title-bar-none fusion-page-title-bar-left">
    <div class="fusion-page-title-row">
        <div class="fusion-page-title-wrapper">
            <div class="fusion-page-title-captions">
                <h1 class="entry-title" data-fontsize="31" data-lineheight="NaN">Cheats Hidden Vegetables</h1>
            </div>
        </div>
    </div>
</div>

功能:

function avada_page_title_bar( $title, $subtitle, $secondary_content ) {
        global $smof_data;
        $post_id = get_queried_object_id();
        // Check for the secondary content
        $content_type = 'none';
        if ( strpos( $secondary_content, 'searchform' ) !== FALSE ) {
            $content_type = 'search';
        } elseif ( $secondary_content != '' ) {
            $content_type = 'breadcrumbs';
        }
        // Check the position of page title
        if ( metadata_exists( 'post', $post_id, 'pyre_page_title_text_alignment' ) && 
             get_post_meta( get_queried_object_id(), 'pyre_page_title_text_alignment', TRUE ) != 'default' 
        ) {
            $alignment = get_post_meta( $post_id, 'pyre_page_title_text_alignment', TRUE );
        } elseif ( $smof_data['page_title_alignment'] ) {
            $alignment = $smof_data['page_title_alignment'];
        }
        // Render the page title bar
        echo sprintf( '<div class="fusion-page-title-bar fusion-page-title-bar-%s fusion-page-title-bar-%s">', $content_type, $alignment );
            echo '<div class="fusion-page-title-row">';
                echo '<div class="fusion-page-title-wrapper">';
                    echo '<div class="fusion-page-title-captions">';
                        if( $title ) {
                            // Add entry-title for rich snippets
                            $entry_title_class = '';
                            if ( ! $smof_data['disable_date_rich_snippet_pages'] ) { 
                                $entry_title_class = ' class="entry-title"';
                            }                   
                            echo sprintf( '<h1%s>%s</h1>', $entry_title_class, $title );
                            if ( $subtitle ) {
                                echo sprintf( '<h3>%s</h3>', $subtitle );
                            }
                        }
                        // Render secondary content on center layout
                        if ( $alignment == 'center') {
                            if ( fusion_get_option( 'page_title_bar_bs', 'page_title_breadcrumbs_search_bar', $post_id ) != 'none' ) {
                                echo '<div class="fusion-page-title-secondary">';
                                    echo $secondary_content;
                                echo '</div>';
                            }
                        }
                    echo '</div>';
                    // Render secondary content on left/right layout
                    if ( $alignment != 'center' ) {
                        if ( fusion_get_option( 'page_title_bar_bs', 'page_title_breadcrumbs_search_bar', $post_id ) != 'none' ) {
                            echo '<div class="fusion-page-title-secondary">';
                                echo $secondary_content;
                            echo '</div>';
                        }
                    }
                echo '</div>';
            echo '</div>';
        echo '</div>';
    }
}