.card-seamless CSS in NestedPanel does not target any element

[tlylt]

Please confirm that you have searched existing issues in the repo

Yes, I have searched the existing issues

Any related issues?

No response

Tell us about your environment

Windows 10

MarkBind version

Master branch

Describe the bug and the steps to reproduce it

In packages/vue-components/src/panels/NestedPanel.vue, there are a few CSS targeting .card-seamless

     .card-seamless {
        padding: 0;
    }
    .card.card-seamless {
        box-shadow: none;
        border: none;
    }

    .card-seamless > .card-heading {
        padding: 0;
    }

    .card-seamless > .card-collapse > hr {
        margin: 0;
        width: calc(100% - 27px);
    }

    .card-seamless > .card-collapse > .card-body {
        padding: 10px 0;
    }

    .card-body > .collapse-button {
        margin-bottom: 13px;
        margin-top: 5px;
        opacity: 0.2;
    }

    .card-body > .collapse-button:hover {
        opacity: 1;
    }

    .card-seamless > .card-collapse > .card-body > .collapse-button {
        position: relative;
        top: 22px;
    }

However, we don't seem to have any element with the card-seamless class. Meaning: whatever CSS effects targeting the card-seamless elements are not working.

At least one minor UI difference that I observed after manually putting the card-seamless class in for a panel element is that the placement of the caret shifts to the side:
Before:

After:
(due to .card-seamless {
padding: 0;
})

Question: is the "Before" or "After" version the intended/preferred styling?

I traced the code back to MarkBind/vue-strap#117 where the .card-seamless was introduced, which also don't seem to have such class -> suggesting that it has not been in action since inception?

@ang-zeyu @damithc do you by any chance have any recollection wrt to this?

Expected behavior

• No unused CSS
• retain intended style if any

Anything else?

If found to be unnecessary CSS, we should remove them accordingly.

[damithc]

Question: is the "Before" or "After" version the intended/preferred styling?

Perhaps the first one, as 'seamless' is meant to minimize differences between an expanded panel and having the content without a panel at all.

[kaixin-hc]

As before is preferred as per prof's comment, I think the move here is to remove the unused CSS, which I'll do in a small PR. Thanks for investigating this!