Various visual bugs

[gsproston-scottlogic]

Bug report

Description

A few visual bugs that might have been caused by #732 .

• [x] Sandbox handbook scrolls into nothing.
• [x] Small close button on some overlays.
• [x] Unexpected document viewer disabled button styling (blue border).

Screenshots

Handbook scroll:

Small close button:

Document viewer button:

Software (please complete the following information):

• Browser: Edge

Additional context

• Happy to have these as separate issues.

Acceptance criteria

GIVEN the user is on sandbox AND has opened the handbook WHEN the user scrolls down through the attacks THEN all the attacks are shown

GIVEN the 'getting started' overlay is open THEN the close button is sized correctly

GIVEN the document viewer is open AND the first document is shown THEN the disabled "previous" button does not have a blue border.

[pmarsh-scottlogic]

To go back to a version when the docViewer scroll and close button were good, try git switch f1d2ade6c9fa3f0bf23813d9414424e27dc3009d --detach

[pmarsh-scottlogic]

When handbook scroll was working

"handbook-overlay" div

• fixed hwight

"content" div

• overflow-y: auto

"handbook-page" article as tall as the the text content within

[pmarsh-scottlogic]

When overlay close button was working

• size determined by text within it. Text size determined by font-size