diff --git a/ui/src/styles/chat/grouped.css b/ui/src/styles/chat/grouped.css
index d80fda0a40c6..fa815ffc793f 100644
--- a/ui/src/styles/chat/grouped.css
+++ b/ui/src/styles/chat/grouped.css
@@ -300,7 +300,7 @@
   padding: 4px;
   min-width: 24px;
   min-height: 24px;
-  border-radius: var(--radius-sm, 4px);
+  border-radius: var(--radius-md);
   color: var(--muted);
   opacity: var(--chat-footer-disclosure-opacity, 0);
   pointer-events: var(--chat-footer-disclosure-pointer-events, none);
@@ -328,7 +328,7 @@
 .chat-group-footer button:hover,
 .chat-message-actions-row button:hover {
   opacity: 1 !important;
-  background: var(--bg-hover, rgba(255, 255, 255, 0.08));
+  background: transparent;
   color: var(--accent);
 }
 
@@ -817,18 +817,23 @@ img.chat-avatar.chat-avatar--logo {
 }
 
 .chat-group.user .chat-bubble:hover {
-  border-color: color-mix(in srgb, var(--accent) 24%, transparent);
+  border-color: transparent;
+  box-shadow: none;
 }
 
-/* Light mode: restore borders. Order contract: stays below the role variants
-   above; it ties with .chat-group.user .chat-bubble on specificity and the
-   light skin must win (user bubbles render on var(--bg) in light mode). */
+/* Light mode: restore borders for surfaces that retain them. */
 :root[data-theme-mode="light"] .chat-bubble {
   border-color: var(--border);
   background: var(--bg);
   box-shadow: inset 0 1px 0 var(--card-highlight);
 }
 
+:root[data-theme-mode="light"] .chat-group.user .chat-bubble {
+  border-color: transparent;
+  background: var(--accent-subtle);
+  box-shadow: none;
+}
+
 :root[data-theme-mode="light"] .chat-bubble--tool-shell,
 :root[data-theme-mode="light"] .chat-group.assistant .chat-bubble {
   border-color: transparent;
@@ -846,7 +851,7 @@ img.chat-avatar.chat-avatar--logo {
 }
 
 .chat-group.user.chat-group--sender-tint .chat-bubble:hover {
-  border-color: hsl(var(--chat-sender-hue) 48% 55% / 0.4);
+  border-color: transparent;
 }
 
 .chat-group.user.chat-group--sender-tint .chat-sender-name {
@@ -855,13 +860,13 @@ img.chat-avatar.chat-avatar--logo {
 
 :root[data-theme-mode="light"] .chat-group.user.chat-group--sender-tint .chat-bubble {
   background: hsl(var(--chat-sender-hue) 65% 94%);
-  border-color: hsl(var(--chat-sender-hue) 45% 82%);
+  border-color: transparent;
 }
 
-/* Outranks the light skin above (it also sets border-color); without this the
-   tinted hover border never applies in light mode. */
+/* Keep tinted user turns borderless when the generic light hover skin applies. */
 :root[data-theme-mode="light"] .chat-group.user.chat-group--sender-tint .chat-bubble:hover {
-  border-color: hsl(var(--chat-sender-hue) 48% 62%);
+  border-color: transparent;
+  box-shadow: none;
 }
 
 :root[data-theme-mode="light"] .chat-group.user.chat-group--sender-tint .chat-sender-name {
diff --git a/ui/src/styles/components.css b/ui/src/styles/components.css
index acce43072ee9..db8c4f9bc603 100644
--- a/ui/src/styles/components.css
+++ b/ui/src/styles/components.css
@@ -3363,8 +3363,9 @@ td.data-table-key-col {
 }
 
 :root[data-theme-mode="light"] .chat-line.user .chat-bubble {
-  border-color: color-mix(in srgb, var(--accent) 20%, transparent);
+  border-color: transparent;
   background: var(--accent-subtle);
+  box-shadow: none;
 }
 
 .chat-line.assistant .chat-bubble {