(Squarespace) Adding 3 buttons under Portfolio Title

To add 3 buttons under Portfolio Title, like this.

or this.

#1 . First, find Portfolio Item URL

In my example, we will have

/projects/harvard-university

/projects/stanford-university

/projects/university-of-oxford

/projects/university-of-cambridge

#2. Next, click Plus icon in Not Linked

#3 . Next, choose Blank Page

#4. Make sure Page Name/URL is

Name: Project Extend

URL Slug: /project-update-text

#5. Add some hyperlink text like this.

We will have result like this

#6. Install this plugin (free plugin)

Plugin will give you some code. You can add it to Code Injection > Footer.

#7. Use this code to Custom CSS.

div.portfolio-description a {
    background-color: #000;
    color: #fff;
    padding:5px 10px;
    display: inline-block;
    margin-bottom: 10px;
}