1. Put the `"octicon-shield-lock"` into the flex container, then it
doesn't need a separate flex box
2. Remove some unnecessary `gt-df` helpers
3. Make `btn` button has the same flex behavior as `ui button`


I think it's better if the primary actions have primary color instead of
green which fits better into the overall single-color UI design. This PR
currently replaces every green button with primary:
<img width="141" alt="Screenshot 2023-09-16 at 14 07 59"
src="843c1e50-4fb2-4ec6-84ba-0efb9472dcbe">
<img width="161" alt="Screenshot 2023-09-16 at 14 07 51"
src="9442195a-a3b2-4a42-b262-8377d6f5c0d1">
Modal actions now use uncolored/primary instead of previous green/red
colors. I also removed the box-shadow on all basic buttons:
<img width="259" alt="Screenshot 2023-09-16 at 14 16 39"
src="5beea529-127a-44b0-8d4c-afa7b034a490">
<img width="261" alt="Screenshot 2023-09-16 at 14 17 42"
src="4757f7b2-4d46-49bc-a797-38bb28437b88">
The change currently includes the "Merge PR" button, for which we might
want to make an exception to match the icon color there:
<img width="442" alt="Screenshot 2023-09-16 at 14 33 53"
src="993ac1a5-c94d-4895-b76c-0d872181a70b">
Replace #26850
Major changes:
1. Remove all `has` selectors, it is still not supported by firefox.
Actually there could be some more general and clearer approaches
2. Remove `two-toggle-buttons`, the `.ui.buttons` just works well
3. Rewrite the `.ui.buttons` border styles, see the screenshots
4. Remove the "fine-tuning" paddings from the the flex children, they
could layout themselves well.




Address
https://github.com/go-gitea/gitea/pull/25163#issuecomment-1599207916
Remove the unused "icon-button".
And fix the layout:
Without the dropdown icon:
```
{{svg "gitea-whitespace"}}
```

With the dropdown icon:
```
{{svg "gitea-whitespace" 16 "gt-mr-3"}}
{{svg "octicon-triangle-down" 14 "dropdown icon"}}
```

Save another 50KB of CSS by removing unused and useless Fomantic
variants.
Removed the last instance if a `tertiary` button and fixed a TODO:
<img width="509" alt="Screenshot 2023-06-15 at 22 34 36"
src="8a16ae7b-2b17-439b-a096-60a52724e3d6">
- Various corrections to button styles, especially secondary
- Remove focus highlight, it's annoying when it stays on button after
press
- Clearly define ghost and link buttons with demos in devtest
- Remove black, grey and tertiary buttons, they should not be used
- Make `arc-green` slightly darker
<img width="1226" alt="image"
src="8d89786a-01ab-40f8-ae5a-e17f40e35084">
<img width="1249" alt="image"
src="83651e6d-3c27-46ff-b8bd-ff344d70e949">
---------
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Giteabot <teabot@gitea.io>
1. Add this button:
<img width="232" alt="Screenshot 2023-05-29 at 15 21 47"
src="5eaf6bd1-83db-4ffc-9503-eda0c59807d2">
<img width="297" alt="Screenshot 2023-05-29 at 15 20 22"
src="708a344f-f6d7-4229-bfda-76e1571b42c8">
2. Correct `button-link` styles to not have a background hover effect.
3. Tweak `.ui.container` padding to be the same for fluid and non-fluid.
4. Misc enhancements to diff header:
Before:
<img width="984" alt="Screenshot 2023-05-29 at 15 38 53"
src="c7926f6a-bd0a-4b05-97ad-c91fc25c62d5">
After:
<img width="987" alt="Screenshot 2023-05-29 at 15 43 10"
src="0149f545-45f8-42cf-b443-e1c76bd5cdeb">