From 4bd714b7be4a5d891ab187a94e64e537cb43809e Mon Sep 17 00:00:00 2001
From: Stephen Tse <Stephen-X@users.noreply.github.com>
Date: Sat, 26 Apr 2025 11:05:51 -0700
Subject: [PATCH] fix(callout): Grid-based callout collapsible animation
 (#1944)

* Fixed broken nested callout maxHeight calculation

* Implemented grid-based callout collapsible
---
 quartz/components/scripts/callout.inline.ts | 29 ++++-----------
 quartz/plugins/transformers/ofm.ts          | 39 +++++++++++++--------
 quartz/styles/callouts.scss                 | 14 ++++++--
 3 files changed, 42 insertions(+), 40 deletions(-)

diff --git a/quartz/components/scripts/callout.inline.ts b/quartz/components/scripts/callout.inline.ts
index 3b7e16d..242ce51 100644
--- a/quartz/components/scripts/callout.inline.ts
+++ b/quartz/components/scripts/callout.inline.ts
@@ -1,25 +1,10 @@
 function toggleCallout(this: HTMLElement) {
   const outerBlock = this.parentElement!
   outerBlock.classList.toggle("is-collapsed")
+  const content = outerBlock.getElementsByClassName("callout-content")[0] as HTMLElement
+  if (!content) return
   const collapsed = outerBlock.classList.contains("is-collapsed")
-  const height = collapsed ? this.scrollHeight : outerBlock.scrollHeight
-  outerBlock.style.maxHeight = height + "px"
-
-  // walk and adjust height of all parents
-  let current = outerBlock
-  let parent = outerBlock.parentElement
-  while (parent) {
-    if (!parent.classList.contains("callout")) {
-      return
-    }
-
-    const collapsed = parent.classList.contains("is-collapsed")
-    const height = collapsed ? parent.scrollHeight : parent.scrollHeight + current.scrollHeight
-    parent.style.maxHeight = height + "px"
-
-    current = parent
-    parent = parent.parentElement
-  }
+  content.style.gridTemplateRows = collapsed ? "0fr" : "1fr"
 }
 
 function setupCallout() {
@@ -27,15 +12,15 @@ function setupCallout() {
     `callout is-collapsible`,
   ) as HTMLCollectionOf<HTMLElement>
   for (const div of collapsible) {
-    const title = div.firstElementChild
-    if (!title) continue
+    const title = div.getElementsByClassName("callout-title")[0] as HTMLElement
+    const content = div.getElementsByClassName("callout-content")[0] as HTMLElement
+    if (!title || !content) continue
 
     title.addEventListener("click", toggleCallout)
     window.addCleanup(() => title.removeEventListener("click", toggleCallout))
 
     const collapsed = div.classList.contains("is-collapsed")
-    const height = collapsed ? title.scrollHeight : div.scrollHeight
-    div.style.maxHeight = height + "px"
+    content.style.gridTemplateRows = collapsed ? "0fr" : "1fr"
   }
 }
 
diff --git a/quartz/plugins/transformers/ofm.ts b/quartz/plugins/transformers/ofm.ts
index 983fd73..e958027 100644
--- a/quartz/plugins/transformers/ofm.ts
+++ b/quartz/plugins/transformers/ofm.ts
@@ -464,6 +464,30 @@ export const ObsidianFlavoredMarkdown: QuartzTransformerPlugin<Partial<Options>>
                   })
                 }
 
+                // For the rest of the MD callout elements other than the title, wrap them with
+                // two nested HTML <div>s (use some hacked mdhast component to achieve this) of
+                // class `callout-content` and `callout-content-inner` respectively for
+                // grid-based collapsible animation.
+                if (calloutContent.length > 0) {
+                  node.children = [
+                    node.children[0],
+                    {
+                      data: { hProperties: { className: ["callout-content"] }, hName: "div" },
+                      type: "blockquote",
+                      children: [
+                        {
+                          data: {
+                            hProperties: { className: ["callout-content-inner"] },
+                            hName: "div",
+                          },
+                          type: "blockquote",
+                          children: [...calloutContent],
+                        },
+                      ],
+                    },
+                  ]
+                }
+
                 // replace first line of blockquote with title and rest of the paragraph text
                 node.children.splice(0, 1, ...blockquoteContent)
 
@@ -485,21 +509,6 @@ export const ObsidianFlavoredMarkdown: QuartzTransformerPlugin<Partial<Options>>
                     "data-callout-metadata": calloutMetaData,
                   },
                 }
-
-                // Add callout-content class to callout body if it has one.
-                if (calloutContent.length > 0) {
-                  const contentData: BlockContent | DefinitionContent = {
-                    data: {
-                      hProperties: {
-                        className: "callout-content",
-                      },
-                      hName: "div",
-                    },
-                    type: "blockquote",
-                    children: [...calloutContent],
-                  }
-                  node.children = [node.children[0], contentData]
-                }
               }
             })
           }
diff --git a/quartz/styles/callouts.scss b/quartz/styles/callouts.scss
index d6f65aa..02921ae 100644
--- a/quartz/styles/callouts.scss
+++ b/quartz/styles/callouts.scss
@@ -7,11 +7,19 @@
   border-radius: 5px;
   padding: 0 1rem;
   overflow-y: hidden;
-  transition: max-height 0.3s ease;
   box-sizing: border-box;
 
-  & > .callout-content > :first-child {
-    margin-top: 0;
+  & > .callout-content {
+    display: grid;
+    transition: grid-template-rows 0.3s ease;
+
+    & > .callout-content-inner {
+      overflow: hidden;
+
+      & > :first-child {
+        margin-top: 0;
+      }
+    }
   }
 
   --callout-icon-note: url('data:image/svg+xml; utf8, <svg xmlns="http://www.w3.org/2000/svg" width="100%" height="100%" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><line x1="18" y1="2" x2="22" y2="6"></line><path d="M7.5 20.5 19 9l-4-4L3.5 16.5 2 22z"></path></svg>');