Used all existing css vars, other migrations are 1:1.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
(cherry picked from commit 34290a00c4501ffeba26db267be71ab68e3ec97f)
Conflicts:
templates/repo/issue/filter_list.tmpl
web_src/js/components/DashboardRepoList.vue
trivial context conflicts