diff --git a/mods/outliner/app.css b/mods/outliner/app.css
index d5dba90..f18c4e0 100644
--- a/mods/outliner/app.css
+++ b/mods/outliner/app.css
@@ -37,21 +37,18 @@
 
 .outline-header a:empty:before {
   color: var(--theme--text_ui_info);
-  content: attr(placeholder);
+  content: attr(outline-placeholder);
   display: block;
 }
-.outline-header.notion-header-block a {
-  text-indent: 0;
-}
-.outline-header.notion-sub_header-block a {
+
+.outline-header[header-level="2"] a {
   text-indent: 18px;
 }
-.outline-header.notion-sub_sub_header-block a {
+.outline-header[header-level="3"] a {
   text-indent: 36px;
 }
 
-.outliner[lined] .notion-sub_header-block::before,
-.outliner[lined] .notion-sub_sub_header-block::before {
+.outliner[lined] .outline-header:not([header-level="1"])::before {
   content: "";
   border-left: solid 1px var(--theme--text_ui_info);
   height: 2.2em;
@@ -60,7 +57,7 @@
   left: 18px;
   pointer-events: none;
 }
-.outliner[lined] .notion-sub_sub_header-block::before {
+.outliner[lined] .outline-header[header-level="3"]::before {
   border-right: solid 1px var(--theme--text_ui_info);
   width: 18px;
 }
diff --git a/mods/outliner/panel.js b/mods/outliner/panel.js
index 00ed19e..9bfe391 100644
--- a/mods/outliner/panel.js
+++ b/mods/outliner/panel.js
@@ -73,9 +73,9 @@ module.exports = (store) => {
       const blockId = block.dataset.blockId.replace(/-/g, '');
       const placeholder = block.querySelector('[placeholder]').getAttribute('placeholder');
       const header = createElement(`
-        <div class="outline-header ${block.classList[1]}">
+        <div class="outline-header" header-level="${placeholder.slice(-1)}">
           <a href="${window.location.pathname}#${blockId}"
-            placeholder="${placeholder}">${block.innerText}</a>
+            outline-placeholder="${placeholder}">${block.innerText}</a>
         </div>
       `);
       outline.append(header);