From dfca9a5b788b26d2bd88c3582ebf4ebeca84da11 Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Sat, 4 Jul 2026 21:04:31 +0000
Subject: [PATCH 1/3] =?UTF-8?q?=F0=9F=8E=A8=20Palette:=20=EB=A7=81?=
 =?UTF-8?q?=ED=81=AC=20=EC=83=81=ED=98=B8=EC=9E=91=EC=9A=A9=20=EC=A0=91?=
 =?UTF-8?q?=EA=B7=BC=EC=84=B1=20=EA=B0=9C=EC=84=A0=20=EB=B0=8F=20CSS=20?=
 =?UTF-8?q?=ED=8A=B8=EB=9E=9C=EC=A7=80=EC=85=98=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .jules/palette.md                     | 4 ++++
 src/main/kotlin/html4tree/main.kt     | 6 ++++++
 src/test/kotlin/html4tree/MainTest.kt | 2 ++
 3 files changed, 12 insertions(+)

diff --git a/.jules/palette.md b/.jules/palette.md
index b8df5bd..e43d4a8 100644
--- a/.jules/palette.md
+++ b/.jules/palette.md
@@ -13,3 +13,7 @@
 ## 2024-06-25 - Directory Listing Navigation Landmark
 **Learning:** Generated directory listings act as navigation regions, and screen readers benefit when the listing is announced separately from the page's main content.
 **Action:** Wrap generated directory listing `<ul>` elements in `<nav aria-label="Directory listing">` while keeping the surrounding semantic `<main>` structure.
+
+## 2024-07-04 - Accessible CSS Transitions for Interactive Elements
+**Learning:** Adding CSS transitions (`transition: all`) can cause unintended animations and negatively impact performance. Moreover, forced animations can trigger motion sickness for users who prefer reduced motion.
+**Action:** When adding hover or focus transitions (e.g., `background-color`, `outline-color`), always specify the exact properties being animated rather than using `all`. Additionally, always include an `@media (prefers-reduced-motion: reduce)` override setting `transition: none` to respect user accessibility preferences.
diff --git a/src/main/kotlin/html4tree/main.kt b/src/main/kotlin/html4tree/main.kt
index 2e2809f..c42d548 100644
--- a/src/main/kotlin/html4tree/main.kt
+++ b/src/main/kotlin/html4tree/main.kt
@@ -143,6 +143,7 @@ fun process_dir(curr_dir: File){
                 text-decoration: none;
                 color: #0366d6;
                 border-radius: 4px;
+                transition: background-color 0.2s, outline-color 0.2s;
               }
               a:hover, a:focus-visible {
                 background-color: #f6f8fa;
@@ -150,6 +151,11 @@ fun process_dir(curr_dir: File){
                 outline: 2px solid #0366d6;
                 outline-offset: -2px;
               }
+              @media (prefers-reduced-motion: reduce) {
+                a {
+                  transition: none;
+                }
+              }
               </style>
               """
 
diff --git a/src/test/kotlin/html4tree/MainTest.kt b/src/test/kotlin/html4tree/MainTest.kt
index e8a3082..3b1b2b0 100644
--- a/src/test/kotlin/html4tree/MainTest.kt
+++ b/src/test/kotlin/html4tree/MainTest.kt
@@ -160,6 +160,8 @@ class MainTest {
         assertFalse(htmlContent.contains("test.ignore"))
         assertTrue(htmlContent.contains("Content-Security-Policy"))
         assertTrue(htmlContent.contains("default-src 'none'; style-src 'unsafe-inline';"))
+        assertTrue(htmlContent.contains("transition: background-color 0.2s, outline-color 0.2s;"))
+        assertTrue(htmlContent.contains("@media (prefers-reduced-motion: reduce)"))
     }
 
     @Test

From 11bb9789372c997896c4fc52aad88b707100eec3 Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Sat, 4 Jul 2026 21:37:04 +0000
Subject: [PATCH 2/3] =?UTF-8?q?=F0=9F=8E=A8=20Palette:=20=EB=A7=81?=
 =?UTF-8?q?=ED=81=AC=20=EC=83=81=ED=98=B8=EC=9E=91=EC=9A=A9=20=EC=A0=91?=
 =?UTF-8?q?=EA=B7=BC=EC=84=B1=20=EA=B0=9C=EC=84=A0=20=EB=B0=8F=20CSS=20?=
 =?UTF-8?q?=ED=8A=B8=EB=9E=9C=EC=A7=80=EC=85=98=20=EC=B6=94=EA=B0=80=20(Re?=
 =?UTF-8?q?try=20CI)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit


From 343ea5bec61327266e278044d189600f6103d0ca Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Sat, 4 Jul 2026 22:16:21 +0000
Subject: [PATCH 3/3] =?UTF-8?q?=F0=9F=8E=A8=20Palette:=20=EB=A7=81?=
 =?UTF-8?q?=ED=81=AC=20=EC=83=81=ED=98=B8=EC=9E=91=EC=9A=A9=20=EC=A0=91?=
 =?UTF-8?q?=EA=B7=BC=EC=84=B1=20=EA=B0=9C=EC=84=A0=20=EB=B0=8F=20CSS=20?=
 =?UTF-8?q?=ED=8A=B8=EB=9E=9C=EC=A7=80=EC=85=98=20=EC=B6=94=EA=B0=80?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit