Reinstate a smaller margin between struct tables

[DMRobertson]

Without a margin, things look poor if the last row is blue: it then
merges into the caption at the top of the next table.

I've also added a small border because I think it helps to break things
up a little.

Before:
After:

Xref: ea42cd3#r79080321 and #1166 (comment)

Preview: https://pr1178--matrix-spec-previews.netlify.app

[richvdh]

looks like a reasonable compromise, I guess.

It does mean that there is a bit of a gap before, for example, the AuthData table at https://pr1178--matrix-spec-previews.netlify.app/client-server-api/#backup-algorithm-mmegolm_backupv1curve25519-aes-sha2.

That lead me into a rabbithole of wondering why other definition tables don't have this problem, and that in turn led me to this bit of CSS. which overrides the margin for a table when it follows an h2 or h3:

matrix-spec/assets/scss/custom.scss

Lines 310 to 312 in 79e3b7e

	h2 + table, h3 + table, h3 + div.highlight {
	margin-top: 0;
	}

I wonder if it would be better to flip this around and instead specify a margin only when a table is followed by another table? wdyt?

[richvdh]

I wonder if it would be better to flip this around and instead specify a margin only when a table is followed by another table? wdyt?

I've done this over at #1192, since I was poking in the area.

I've also added a small border because I think it helps to break things up a little.

I don't disagree, but it also adds a second line after the 'Requires authentication' line, which looks a bit odd. I'm working on some other changes which I hope will make this easier.

[DMRobertson]

Is this now superseded/made defunct by #1192?

It does mean that there is a bit of a gap before, for example, the AuthData table at pr1178--matrix-spec-previews.netlify.app/client-server-api/#backup-algorithm-mmegolm_backupv1curve25519-aes-sha2.

Arg, yes. Some more classes on the tables would help here.

That lead me into a rabbithole of wondering why other definition tables don't have this problem, and that in turn led me to this bit of CSS. which overrides the margin for a table when it follows an h2 or h3:

matrix-spec/assets/scss/custom.scss

Lines 310 to 312 in 79e3b7e

	h2 + table, h3 + table, h3 + div.highlight {
	margin-top: 0;
	}

I wonder if it would be better to flip this around and instead specify a margin only when a table is followed by another table? wdyt?

I'm kind of surprised we need those kind of selectors, given that margin collapse is A Thing. But I'm naive and my CSS knowledge is largely stuck in the previous decade. No strong opinions though.

[richvdh]

Is this now superseded/made defunct by #1192?

I think so? But up to you to figure out if there's anything here that you still want.

I'm kind of surprised we need those kind of selectors, given that margin collapse is A Thing. But I'm naive and my CSS knowledge is largely stuck in the previous decade.

You and me both. There may well be better ways to do this.

[DMRobertson]

But up to you to figure out if there's anything here that you still want.

Looking at your changes as rendered on https://spec.matrix.org/unstable/client-server-api/ I'm happy---the original complaint is fixed. Thanks!