I searched for this topic, but the replies looks not related to my current version.
Bootstrap Studio 7.0.3.
How-to import:
├── assets
│ ├── bootstrap
│ │ ├── css
│ │ │ └── bootstrap.min.css
│ │ └── js
│ │ └── bootstrap.min.js
│ └── img
│ ├── image1.jpg
│ ├── image2.jpg
│ ├── image3.jpg
│ └── image4.jpg
└── index.html
into Bootstrap Studio.
Thank you.