RC: Remove emotion and move to CSS

[rzkhosroshahi]

Emotion has lots of benefits, you can add custom and dynamic CSS and use JS power at the same time. but it comes with at least 25KB (gzip) bundle size and in our Zaman lib case there is no critical need to use emotion all styles which Zaman can easily rewrite by the CSS. so I decided to rewrite styles with CSS.

befits:

• decrease bundle size

cost:

• Zaman accepts accent colors and makes a theme for your date-picker with this change we gonna lose the feature of having two separate theme colors at the same time. it's not a big deal because it doesn't make sense to have this feature in product POV but anyway...