🦴 Add theme page backbone

packages/bot-engine/src/services/theme.ts

@@ -0,0 +1,25 @@
+import { BackgroundType, Theme } from '../models'
+
+const cssVariableNames = {
+  container: {
+    bg: {
+      image: '--typebot-container-bg-image',
+      color: '--typebot-container-bg-color',
+    },
+    fontFamily: '--typebot-container-font-family',
+  },
+}
+
+export const setCssVariablesValue = (
+  theme: Theme,
+  documentStyle: CSSStyleDeclaration
+) => {
+  const { background, font } = theme.general
+  documentStyle.setProperty(
+    background.type === BackgroundType.IMAGE
+      ? cssVariableNames.container.bg.image
+      : cssVariableNames.container.bg.color,
+    background.content
+  )
+  documentStyle.setProperty(cssVariableNames.container.fontFamily, font)
+}