💄(boxes) screen boxes are not at all boxes now

this is meant to be updated soon, it's not ideal at all. This Screen/Box
stuff is really meh anyway, needs some rework.

src/frontend/panda.config.ts

@@ -166,7 +166,7 @@ const config: Config = {
       colors: {
         default: {
           text: { value: '{colors.gray.900}' },
-          bg: { value: '{colors.slate.50}' },
+          bg: { value: 'white' },
           subtle: { value: '{colors.gray.100}' },
           'subtle-text': { value: '{colors.gray.600}' },
         },

src/frontend/src/primitives/Box.tsx

@@ -16,6 +16,8 @@ const box = cva({
         width: '38rem',
         maxWidth: '100%',
         textAlign: 'center',
+        borderColor: 'transparent',
+        paddingY: 0,
       },
       popover: {
         padding: 'boxPadding.xs',