How can I set up a scrollable list on my page?

Hey folks, I'd like to make a change to my site and need your help.

I want to add a scrollable list to my page. For this, I'd like to upload a PNG where only the top part is shown, and then users can scroll down, similar to scrolling through a website.

I found the following code for this:
 

// Scrollable Webpage
#BLOCK-ID {
  height: 350px;
  max-width: 80%;
  margin:auto;
  width: 100%;
  overflow-y:scroll;
  overflow-x:hidden;
  filter: drop-shadow(10px 10px 10px rgba(0,0,0,.3));
  
  @media screen and (max-width:767px) {
   height:200px;
  }
}

//Customize the scrollbar

::-webkit-scrollbar {
    width: 3px; /* Scrollbar Thickness */
    height:15px;
}
::-webkit-scrollbar-thumb {
    background: #22514A; 
}
::-webkit-scrollbar-track {
    background: #ffffff; /* Background Color */
}

Unfortunately, it doesn't work as it did in the tutorial. Can someone help me with this? How can I achieve a scrollable list like this? Appreciate your assistance!

Site: https://maltemartenmethod.squarespace.com/module-1
Pword: maltemartenmethod2023

Turorial Example:

Have you replace #BLOCK-ID with your image block id yet? Use this tool to find id

https://chrome.google.com/webstore/detail/squarespace-id-finder/igjamfnifnkmecjidfbdipieoaeghcff

Yes @tuanphan, I have already done that. Something is happening, but the result doesn't look as it should. See the attached screenshot or here on the page: https://maltemartenmethod.squarespace.com/module-1

Can you help me with this?

5 hours ago, Nomis said:

Yes @tuanphan, I have already done that. Something is happening, but the result doesn't look as it should. See the attached screenshot or here on the page: https://maltemartenmethod.squarespace.com/module-1

Can you help me with this?

You try Classic Section for current section and test code again