Align angular theme to the new lit theme for the restaurant sample apps

[josemontespg]

@josemontespg I landed the styling changes for angular. You could potentially rebase this PR and apply this stylesheet to make the sample look more like the Lit one? And see what I ended up messing up in the Angular theming :P

Originally posted by @ditman in #1189 (comment)

[ditman]

PR Posted!