How to add a divider line between two web parts?

Question

I want to add a horizontal dark line underneath my web parts to separate each. How do I need to go about doing this?

Answer 1

If it is modern page (site page), you can use Divider web part to add a line between web parts.

If it is a classic page, you can add a Script Editor web part between the web parts and enter html such as <hr/> in a Script Editor web part as horizontal line.

Or, create the custom text style with the following scripts as horizontal line.

/*extensions*/
/*page elements*/
span.ms-rteElement-CustomHRElement{
    -ms-name:"HR in page elements";
    background-color: #b6b6b6;
    height: 1px;
    width:100%;
    display:block;
}
/*text styles*/
.ms-rteStyle-CustomHRStyle{
    -ms-name:"HR in text styles";
    background-color: #b6b6b6;
    height: 1px;
    width:100%;
    display:block;
}

Refer to Horizontal Rule in Content Editor Web Part? for more information.