feat: add variant hint-modal to modal component (#764)

Co-authored-by: Dominik Pschenitschni <mail@celement.de>
Co-authored-by: kolaente <k@knt.li>
Reviewed-on: https://kolaente.dev/vikunja/frontend/pulls/764
Reviewed-by: konrad <k@knt.li>
Co-authored-by: dpschen <dpschen@noreply.kolaente.de>
Co-committed-by: dpschen <dpschen@noreply.kolaente.de>

src/styles/theme/navigation.scss

@@ -1,5 +1,3 @@
-@use "sass:math";
-
 .navbar {
 	z-index: 4 !important;
 

src/styles/theme/variables-derived.scss

@@ -1,4 +1,2 @@
-@use "sass:math";
-
 // Variables that are derived from bulma variables need to be included after them
 $mobile: math.div($tablet, 2);