This is an Elementor page template that consists of 18 sections whereby on each section you will find a three-color gradient background.
The gradient on each section is created using custom CSS. So, before importing the template make sure you already installed and activated the pro version of Elementor. Custom CSS is a feature that is only available on Elementor Pro.
You can read our article here if you want to learn how to create a multi-color gradient in Elementor