0.10: Accordion Styling example
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**Primary Actor**: User

**Scope**: Ngx-bootstrap DEMO / BS version 3&4

**Goal**: Show user how to use different styles for each accordion item

Main success scenario:
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1. User open Accordion demo page
2. User click on Styling sub-menu
3. User able to click on each item of 3, first item is opened by default
4. Styles for the 1st and 3d items should be the same (from the customClass styles)
5. Styles for the content inside 1st and 3d items should be the same (from the customClass styles)
6. Styles for the 2d item and content should be default

Variations:
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2*. User scroll to Styling sub-menu