Calendar: design specs

[ciampo]

Notes:

• individual dates are re-using the same styles as the default variant of the Button component
  • selected dates are using the "pressed" variant, even though we may not be able to do so for semantics/accessibility reasons
• the selected range is highlighted with a light gray background color
• disabled dates are grayed out
• today's date is marked with an outline

81AKtBrnUn5yfXUuWm3jG2-fi