This tutorial shows the capabilities of styling page sections and its contents in Google Sites. While it has its strength with more simple settings, you could have a hard time figuring out what to do, if you like to have it in a more custom way using image backgrounds, e.g. There are some workarounds and compromises, but you need to consider, what you like to have: A nice colourful design or easy maintainability.
WHITE
DARK GREY
LIGHT GREY
PURPLE
LIGHT BLUE
BLUE
LIGHT RED
RED
LIGHT GREEN
GREEN
LIGHT YELLOW
YELLOW
This comment (code font < > feature) uses the standard font colour and custom font "Lato" in 'normal text' style definition.
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A comment using Code font < > "Source Code Pro"
How it looks in the editor:
How it looks like on the published site:
The colours of the drop down arrow and the divider for the collapsible group doesn't match in editing mode, one dark/light! However on the published Site it shows the undesired and not very recognisable light grey for both. Open the collapsible group to find proof of it.
In the Style 1 and 2 sections I have changed the divider colour. The default is a transparent black #00000026. Once you have chosen another colour, you can't go back to transparent or make those colors partially transparent as the Google Sites Editor does not let you type in the necessary additional numbers. So be careful while testing!
...with this background image in light blue colour (HEX code: #CFE2F3)
...not adjusted for readability:
https://placehold.co/10x10/cfe2f3/cfe2f3.png
...with switched colours for the heading background (HEX code: #0041A5) and font colour
https://placehold.co/10x10/0041a5/0041a5.png
The divider has white background as it uses the default colour (style 1), so not very suitable here. I would like to have blue here. Section 2 and 3 colours work with dividers. Dividers normally inherit the background colour from the section above them. By the way: Spacers are recognised as separate sections and therefore can have an own background colour or image, see:
What a pity, that this does not work the same way for dividers!
When adding the background image, the Google Sites editor automatically adjusts for readability first (see part 2). If you disable this adjustment the text colour is not recalculated for this light background (light grey on light blue).
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...with this background image in light blue colour (HEX code: #CFE2F3)
...this time automatically adjusted for readability:
https://placehold.co/10x10/cfe2f3/cfe2f3.png
Well, now it's medium greyish instead of light blueish! Colours are suitable though.
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⚠️ Hover over the bottom right corner of a section. 2 buttons will appear:
Readability adjustment
Anchoring of the background image
You need to manually adjust every single textual content (give it the desired colours) and only the filled button makes sense in terms of readability. Arrow and divider colours for the collapsible group can't be adjusted.
Disadvantages: You lose the automatic adjustment from the theme's settings. You can't copy it and change to style 1, 2, 3 easily anymore. You need to go into every text box and clear the formatting. An option to reset the whole section would be nice! There is no adjustment for the active dot in image carousels. It uses the default (section 1) one. That's why I have chosen the neutral colour of dark grey!
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fixes the button issue
uses a custom method of collapsible text
⚠️ Note: Embedded content is not indexable in Google Search as it is placed in a nested sanitised <iframe>