> ## Documentation Index > Fetch the complete documentation index at: https://docs.alignet.com/llms.txt > Use this file to discover all available pages before exploring further. # Library and basic styles > Add the Alignet One Flex library to your web application. To be used Alignet One Flex have to include the following code in the HTML from the page by environment: ```html theme={"system"} theme={"system"} ``` ```html theme={"system"} theme={"system"} ``` Undetermined terms of the payment form. Include before closure ``. Main library Alignet One Flex. Include after CSS at ``. Be sure to first include CSS and then JS to ensure that styles are applied correctly before the form starts.