Use styling from Pillar

src/styles/_welcome.sass

@@ -264,22 +264,6 @@
 			+media-xs
 				margin-top: 20px
 
-	.navbar
-		.nav-item-sign-in
-			a.navbar-item
-				background-color: $color-primary
-				border: none
-				border-radius: 3px
-				color: white
-				height: auto
-				font-weight: bold
-				margin-top: 5px
-				margin-left: 10px
-				padding: 10px 20px
-
-				&:hover
-					background-color: lighten($color-primary, 10%)
-					box-shadow: none
 
 .container.wide-on-sm
 	+media-sm

src/styles/main.sass

@@ -7,19 +7,6 @@
 @import "../../../pillar/src/styles/config"
 @import "../../../pillar/src/styles/utils"
 
-$primary: $color-primary
-
-$body-bg: $color-background
-$body-color: $color-text
-
-$color-background-nav: #fff
-$link-color: $primary
-
-$font-family-sans-serif: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, Helvetica, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji"
-$font-size-base: .9rem
-
-$dropdown-border-width: 0
-$dropdown-box-shadow: 0 10px 25px rgba($black, .1)
 
 // Bootstrap components.
 @import "../../node_modules/bootstrap/scss/root"