Hi,

Using a <style> tag inside the report template is a valid and effective solution for applying CSS styles to PDF reports in Odoo. This approach ensures that the styles are embedded directly in the HTML content that is passed to wkhtmltopdf, avoiding issues with external stylesheets not being loaded correctly.

Here’s how you can use the <style> tag in your QWeb report template:

Eg:

<t t-call="web.external_layout">

            <div class="page">

                <!-- Add a <style> tag for CSS -->

                <style>

                    h1 {

                        color: red;

                        font-size: 24px;

                    }

                    p {

                        color: blue;

                        font-size: 14px;

                    }

                    .custom-class {

                        background-color: #f0f0f0;

                        padding: 10px;

                    }

                </style>

                <!-- Report Content -->

                <h1>Custom Report</h1>

                <p>This is a sample report with embedded styles.</p>

                <div class="custom-class">

                    This is a styled div.

                </div>

            </div>

        </t>

Alternative: Use a Common <style> Template

If you want to reuse styles across multiple reports, you can define a common <style> template and inherit it in your reports

Hope it helps