## Filter: wpdai_email_template_styles

Filter the CSS styles used in Alpha Insights email templates before they are output in the `<style>` tag.

### Description

Email templates include inline styles for compatibility with email clients. The plugin builds a string of CSS and outputs it inside a `<style type="text/css">` block. This filter receives that CSS string so you can add or override styles (e.g. brand colors, fonts, or layout). The filtered value is escaped with `esc_html()` when output.

#### Location

File: `includes/emails/wpd-email-template_styles.php`

Context: Before the style block is echoed into the email template.

### Parameters

Parameter | Type | Description
--- | --- | ---
$email_styles | string | The CSS content for the email template (rules and declarations)

#### Return

Type: string

The (possibly modified) CSS string. Keep valid CSS; the output is escaped for HTML context.

### Example Usage

#### Add brand colors to emails

    add_filter( 'wpdai_email_template_styles', 'add_brand_email_styles' );
    function add_brand_email_styles( $email_styles ) {
        $extra = '
            .wpd-email-header { background-color: #1a1a2e !important; }
            .wpd-email-button { background-color: #e94560 !important; }
        ';
        return $email_styles . $extra;
    }

#### Override font family

    add_filter( 'wpdai_email_template_styles', 'override_email_font' );
    function override_email_font( $email_styles ) {
        $email_styles = str_replace( 'font-family: sans-serif', 'font-family: "Helvetica Neue", Helvetica, Arial, sans-serif', $email_styles );
        return $email_styles;
    }

### Best Practices

- Use inline-friendly CSS; many email clients strip or ignore external stylesheets.
- Append or replace specific rules rather than stripping required layout styles.
- Do not include user-controlled or unsanitized input in the CSS string.