diff --git a/components/block-cart-note/assets/block-cart-note.js b/components/block-cart-note/assets/block-cart-note.js
index 20fbc28..e2ef77c 100644
--- a/components/block-cart-note/assets/block-cart-note.js
+++ b/components/block-cart-note/assets/block-cart-note.js
@@ -1,8 +1,19 @@
-export class CartNote extends HTMLElement {
+import { HTMLSectionElement } from '@archetype-themes/custom-elements/section'
+
+export class CartNote extends HTMLSectionElement {
   connectedCallback() {
+    super.connectedCallback()
     this.addEventListener('change', this.handleChange.bind(this))
   }
 
+  onBlockSelect() {
+    this.style.outline = '2px solid coral'
+  }
+
+  onBlockDeselect() {
+    this.style.outline = 'none'
+  }
+
   async handleChange({ target }) {
     if (target.getAttribute('name') !== 'note') return
 
@@ -10,7 +21,7 @@ export class CartNote extends HTMLElement {
   }
 
   async updateCart(body) {
-    const response = await fetch(`${window.Shopify.routes.root}cart/update.js`, {
+    const response = await fetch(`${Shopify.routes.root}cart/update.js`, {
       method: 'POST',
       headers: { 'Content-type': 'application/json' },
       body: JSON.stringify(body),
diff --git a/scripts/custom-elements/section.js b/scripts/custom-elements/section.js
new file mode 100644
index 0000000..1c1f4fa
--- /dev/null
+++ b/scripts/custom-elements/section.js
@@ -0,0 +1,84 @@
+const ThemeEditorEventHandlerMixin = (Base) =>
+  class extends Base {
+    connectedCallback() {
+      if (Shopify.designMode) {
+        this.boundEventMap = this.createThemeEditorEventMap()
+
+        Object.entries(this.boundEventMap).forEach(([event, boundHandler]) => {
+          const target = event.includes('section') ? document : this
+          target.addEventListener(event, boundHandler)
+        })
+
+        if (typeof this.onSectionLoad === 'function') {
+          this.onSectionLoad()
+        }
+      }
+    }
+
+    disconnectedCallback() {
+      if (Shopify.designMode) {
+        Object.entries(this.boundEventMap).forEach(([event, boundHandler]) => {
+          if (event.includes('section')) {
+            document.removeEventListener(event, boundHandler)
+          }
+        })
+
+        if (typeof this.onSectionUnload === 'function') {
+          this.onSectionUnload()
+        }
+      }
+    }
+
+    createThemeEditorEventMap() {
+      const events = [
+        'shopify:section:select',
+        'shopify:section:deselect',
+        'shopify:section:reorder',
+        'shopify:block:select',
+        'shopify:block:deselect'
+      ]
+
+      return events.reduce((acc, eventName) => {
+        const methodName = this.convertEventToMethodName(eventName)
+
+        if (typeof this[methodName] === 'function') {
+          acc[eventName] = this.createEventBoundHandler(this[methodName])
+        }
+
+        return acc
+      }, {})
+    }
+
+    convertEventToMethodName(eventName) {
+      const capitalize = (str) => {
+        return str.charAt(0).toUpperCase() + str.slice(1)
+      }
+
+      return `on${eventName.split(':').slice(1).map(capitalize).join('')}`
+    }
+
+    createEventBoundHandler(handler) {
+      return (event) => {
+        if (event.detail && event.detail.sectionId === this.sectionId) {
+          handler.call(this, event)
+        }
+      }
+    }
+  }
+
+class Section extends HTMLElement {
+  get sectionId() {
+    if (!this._sectionId) {
+      this._sectionId = this.getAttribute('section-id') || this.extractSectionId(this)
+    }
+
+    return this._sectionId
+  }
+
+  extractSectionId(element) {
+    element = element.classList.contains('shopify-section') ? element : element.closest('.shopify-section')
+    return element.id.replace('shopify-section-', '')
+  }
+}
+
+export class HTMLSectionElement extends ThemeEditorEventHandlerMixin(Section) {}