Scrolling text

https://www.nosegraze.com/scrolling-text-box/

1. Some themes might have a “Custom CSS” box in the settings panel. You can paste it there.
2. If you have Jetpack installed, you should have a section in Appearance » Edit CSS where you can paste custom CSS code.
3. Or, you can install and activate the Simple Custom CSS plugin, which will add a new menu under Appearance for custom CSS.

Here’s the actual code you want to add:

.scroll-box {
    height: 400px; /* maximum height of the box, feel free to change this! */
    overflow-y: scroll;
}

If you want, you can also add some extra styling to add a background colour or border. Here are some simple, extra styles:

.scroll-box { background: #f4f4f4; border: 2px solid rgba(0, 0, 0, 0.1); height: 400px; /* maximum height of the box, feel free to change this! */ padding: 15px; overflow-y: scroll; }

Next add that to blog:
<div class="scroll-box">

<p>Your excerpt goes in here!</p>

</div>