* Refactor `i18n` to `locale`
- Currently we're using the `i18n` variable naming for the `locale`
struct. This contains locale's specific information and cannot be used
for general i18n purpose, therefore refactoring it to `locale` makes
more sense.
- Ref: https://github.com/go-gitea/gitea/pull/20096#discussion_r906699200
* Update routers/install/install.go
* make blue really blue
* replace blue button and label classes with primary
* add --color-blue-dark
* add light color variants, tweak a few colors
* fix colors
* add comment
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
