diff --git a/CHANGELOG.md b/CHANGELOG.md
index 453f4af4b..48cc84fdf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@ Only write entries that are worth mentioning to users.
 
 ## Unreleased
 
+- Web: Refine UI details including rounded corners, spacing, and layout adjustments across input group, slash command menu, and session sidebar
+
 ## 1.12.0 (2026-02-11)
 
 - Web: Add subagent activity rendering to display subagent steps (thinking, tool calls, text) inside Task tool messages
diff --git a/docs/en/release-notes/changelog.md b/docs/en/release-notes/changelog.md
index 9b27f34e8..0860fd0ee 100644
--- a/docs/en/release-notes/changelog.md
+++ b/docs/en/release-notes/changelog.md
@@ -4,6 +4,8 @@ This page documents the changes in each Kimi Code CLI release.
 
 ## Unreleased
 
+- Web: Refine UI details including rounded corners, spacing, and layout adjustments across input group, slash command menu, and session sidebar
+
 ## 1.12.0 (2026-02-11)
 
 - Web: Add subagent activity rendering to display subagent steps (thinking, tool calls, text) inside Task tool messages
diff --git a/docs/zh/release-notes/changelog.md b/docs/zh/release-notes/changelog.md
index 5f4ef685d..7a882caf4 100644
--- a/docs/zh/release-notes/changelog.md
+++ b/docs/zh/release-notes/changelog.md
@@ -4,6 +4,8 @@
 
 ## 未发布
 
+- Web：优化 UI 细节，包括输入框、斜杠命令菜单和会话侧边栏的圆角、间距和布局调整
+
 ## 1.12.0 (2026-02-11)
 
 - Web：添加子 Agent 活动渲染，在 Task 工具消息中展示子 Agent 步骤（思考、工具调用、文本）
diff --git a/web/src/App.tsx b/web/src/App.tsx
index 26db2bab7..9400928ee 100644
--- a/web/src/App.tsx
+++ b/web/src/App.tsx
@@ -360,7 +360,7 @@ function App() {
 
   return (
     <PromptInputProvider>
-      <div className="box-border flex h-[100dvh] flex-col bg-background text-foreground px-[calc(0.75rem+var(--safe-left))] pr-[calc(0.75rem+var(--safe-right))] pt-[calc(0.75rem+var(--safe-top))] pb-1 lg:pb-[calc(0.75rem+var(--safe-bottom))] max-lg:h-[100svh] max-lg:overflow-hidden">
+      <div className="box-border flex h-dvh flex-col bg-background text-foreground px-(--safe-left) pr-(--safe-right) pt-(--safe-top) pb-1 lg:pb-(--safe-bottom) max-lg:h-svh max-lg:overflow-hidden">
         <div className="mx-auto flex h-full min-h-0 w-full flex-1 flex-col gap-2 max-w-none">
           {isDesktop ? (
             <ResizablePanelGroup
@@ -447,7 +447,7 @@ function App() {
                     searchQuery={searchQuery}
                     onSearchQueryChange={handleSearchQueryChange}
                   />
-                  <div className="mt-auto flex items-center justify-between pl-2 pb-2 pr-2">
+                  <div className="mt-auto flex items-center justify-between px-3 pb-3">
                     <div className="flex items-center gap-2">
                       <ThemeToggle />
                     </div>
diff --git a/web/src/components/ai-elements/prompt-input.tsx b/web/src/components/ai-elements/prompt-input.tsx
index 65497b58b..68f1afe77 100644
--- a/web/src/components/ai-elements/prompt-input.tsx
+++ b/web/src/components/ai-elements/prompt-input.tsx
@@ -1186,7 +1186,7 @@ export const PromptInputSubmit = ({
   return (
     <InputGroupButton
       aria-label="Submit"
-      className={cn(className)}
+      className={cn("rounded-full",className)}
       size={size}
       type="submit"
       variant={variant}
diff --git a/web/src/components/ui/input-group.tsx b/web/src/components/ui/input-group.tsx
index 85dfc22bb..8520df4ca 100644
--- a/web/src/components/ui/input-group.tsx
+++ b/web/src/components/ui/input-group.tsx
@@ -14,7 +14,7 @@ function InputGroup({ className, ...props }: React.ComponentProps<"div">) {
       data-slot="input-group"
       role="group"
       className={cn(
-        "group/input-group border-input dark:bg-input/30 relative flex w-full items-center rounded-md border shadow-xs transition-[color,box-shadow] outline-none",
+        "group/input-group border-input dark:bg-input/30 relative flex w-full items-center rounded-3xl border shadow-xs transition-[color,box-shadow] outline-none",
         "h-9 min-w-0 has-[>textarea]:h-auto",
 
         // Variants based on alignment.
@@ -46,9 +46,9 @@ const inputGroupAddonVariants = cva(
         "inline-end":
           "order-last pr-3 has-[>button]:mr-[-0.45rem] has-[>kbd]:mr-[-0.35rem]",
         "block-start":
-          "order-first w-full justify-start px-3 pt-3 [.border-b]:pb-3 group-has-[>input]/input-group:pt-2.5",
+          "order-first w-full justify-start px-2 pt-2 [.border-b]:pb-3 group-has-[>input]/input-group:pt-2.5",
         "block-end":
-          "order-last w-full justify-start px-3 pb-3 [.border-t]:pt-3 group-has-[>input]/input-group:pb-2.5",
+          "order-last w-full justify-start px-2 pb-2 [.border-t]:pt-3 group-has-[>input]/input-group:pb-2.5",
       },
     },
     defaultVariants: {
diff --git a/web/src/features/chat/chat.tsx b/web/src/features/chat/chat.tsx
index ab2362883..7d43e2c59 100644
--- a/web/src/features/chat/chat.tsx
+++ b/web/src/features/chat/chat.tsx
@@ -245,7 +245,7 @@ export const ChatWorkspace = memo(function ChatWorkspaceComponent({
         />
 
         {currentSession && (
-          <div className="mt-auto flex-shrink-0 px-0 pb-0 pt-0 sm:px-3 sm:pb-3 ">
+          <div className="mt-auto shrink-0 px-3 pb-3 ">
             <ChatPromptComposer
               status={status}
               onSubmit={onSubmit}
diff --git a/web/src/features/chat/components/chat-prompt-composer.tsx b/web/src/features/chat/components/chat-prompt-composer.tsx
index 251c27abb..1f8c1688d 100644
--- a/web/src/features/chat/components/chat-prompt-composer.tsx
+++ b/web/src/features/chat/components/chat-prompt-composer.tsx
@@ -213,7 +213,7 @@ export const ChatPromptComposer = memo(function ChatPromptComposerComponent({
             type="button"
             onClick={handleToggleExpand}
             disabled={!(canSendMessage && currentSession)}
-            className="absolute top-2 right-2 z-10 p-1 cursor-pointer rounded-md text-muted-foreground hover:text-foreground hover:bg-secondary/50 transition-colors disabled:opacity-50 disabled:pointer-events-none"
+            className="absolute top-2 right-2 z-10 p-1 cursor-pointer rounded-full text-muted-foreground hover:text-foreground hover:bg-secondary/50 transition-colors disabled:opacity-50 disabled:pointer-events-none size-8 flex items-center justify-center"
             aria-label={isExpanded ? "Collapse input" : "Expand input"}
           >
             {isExpanded ? (
@@ -292,7 +292,7 @@ export const ChatPromptComposer = memo(function ChatPromptComposerComponent({
             </div>
           </div>
         </PromptInputBody>
-        <PromptInputFooter className="w-full gap-2 py-1 border-none bg-transparent shadow-none">
+        <PromptInputFooter className="w-full gap-2 pb-2 border-none bg-transparent shadow-none">
           <PromptInputTools className="flex-1 min-w-0 flex-wrap">
             <GlobalConfigControls />
           </PromptInputTools>
diff --git a/web/src/features/chat/global-config-controls.tsx b/web/src/features/chat/global-config-controls.tsx
index 590287190..c2f9dc2a5 100644
--- a/web/src/features/chat/global-config-controls.tsx
+++ b/web/src/features/chat/global-config-controls.tsx
@@ -200,8 +200,8 @@ export function GlobalConfigControls({
     <div className={cn("flex items-center gap-1", className)}>
       <Button
         variant="ghost"
-        size="icon"
-        className="size-9 border-0"
+        size="icon-sm"
+        className="border-0 rounded-full"
         aria-label="Attach files"
         onClick={() => attachments.openFileDialog()}
       >
@@ -215,7 +215,7 @@ export function GlobalConfigControls({
           <Button
             variant="ghost"
             size="sm"
-            className="h-9 max-w-[160px] justify-start gap-2 border-0"
+            className="max-w-40 justify-start gap-2 border-0 rounded-full"
             aria-label="Change global model"
             disabled={isLoading || isUpdating || !config}
           >
diff --git a/web/src/features/chat/slash-command-menu.tsx b/web/src/features/chat/slash-command-menu.tsx
index d4bc75e58..0cbdcad04 100644
--- a/web/src/features/chat/slash-command-menu.tsx
+++ b/web/src/features/chat/slash-command-menu.tsx
@@ -39,7 +39,7 @@ export const SlashCommandMenu = ({
 
   return (
     <div className="absolute left-0 right-0 bottom-[calc(100%+0.75rem)] z-30">
-      <div className="rounded-xl border border-border/80 bg-popover/95 p-2 px-1 shadow-xl backdrop-blur supports-backdrop-filter:bg-popover/80">
+      <div className="rounded-2xl border border-border/80 bg-popover/95 p-2 px-1 shadow-xl backdrop-blur supports-backdrop-filter:bg-popover/80">
         {options.length > 0 ? (
           <>
             <div className="px-3 pb-1 text-[10px] font-semibold uppercase tracking-wide text-muted-foreground">
diff --git a/web/src/features/sessions/sessions.tsx b/web/src/features/sessions/sessions.tsx
index 5d5e9e66d..d1b5fe3a4 100644
--- a/web/src/features/sessions/sessions.tsx
+++ b/web/src/features/sessions/sessions.tsx
@@ -145,7 +145,7 @@ function SessionsListComponent(
 ) {
   const { className, ...rest } = props;
   return (
-    <div ref={ref} className={cn("flex flex-col space-y-0.5 w-full px-2 mt-1", className)} {...rest} />
+    <div ref={ref} className={cn("flex flex-col gap-1 w-full px-3 pt-px!", className)} {...rest} />
   );
 }
 
@@ -612,7 +612,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
     <>
       <aside className="flex h-full min-h-0 flex-col">
         <div className="flex min-h-0 flex-1 flex-col gap-2 overflow-hidden">
-          <div className="flex items-center justify-between px-3 pt-2">
+          <div className="flex items-center justify-between p-3">
             <KimiCliBrand size="sm" showVersion={true} />
             {onClose && (
               <button
@@ -627,7 +627,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
           </div>
 
           {/* Sessions */}
-          <div className="flex items-center justify-between px-3 pt-3">
+          <div className="flex items-center justify-between px-3">
             <h4 className="text-xs font-medium text-muted-foreground uppercase tracking-wide">Sessions</h4>
             <div className="flex items-center gap-1">
               <button
@@ -668,7 +668,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
 
           {/* Multi-select action bar */}
           {isMultiSelectMode && (
-            <div className="mx-2 flex items-center justify-between gap-2 rounded-md bg-secondary/80 px-2 py-1.5">
+            <div className="mx-3 flex items-center justify-between gap-2 rounded-md bg-secondary/80 pl-2 pr-0.5 py-0.5">
               {/* Left: checkbox toggle and count */}
               <div className="flex items-center gap-1.5">
                 <button
@@ -774,7 +774,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
 
           {/* Session search and view toggle */}
           {!isMultiSelectMode && (
-          <div className="px-2 flex items-center gap-2">
+          <div className="px-3 flex items-center gap-2">
             <div className="relative flex-1 min-w-0">
               <Search className="absolute left-2.5 top-1/2 size-3.5 -translate-y-1/2 text-muted-foreground" />
               <input
@@ -816,7 +816,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
             <div className="flex-1 min-h-0">
             {viewMode === "grouped" ? (
               <div className="flex h-full flex-col">
-                <div className="flex-1 overflow-y-auto overflow-x-hidden [-webkit-overflow-scrolling:touch] px-3 pb-4 pr-1">
+                <div className="flex-1 overflow-y-auto overflow-x-hidden [-webkit-overflow-scrolling:touch] px-3 pb-4">
                   <ul className="space-y-1">
                     {sessionGroups.map((group) => (
                       <li key={group.workDir} className="group/dir">
@@ -898,7 +898,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
                                               }
                                             }}
                                             onClick={(e) => e.stopPropagation()}
-                                            className="w-full text-sm font-medium text-foreground bg-background border border-input rounded px-2 py-1 focus:outline-none focus:ring-1 focus:ring-ring"
+                                            className="w-full text-sm font-medium text-foreground border-b border-input focus:outline-none"
                                           />
                                         ) : (
                                           <Tooltip delayDuration={500}>
@@ -1018,13 +1018,13 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
                               }
                             }}
                             onClick={(e) => e.stopPropagation()}
-                            className="w-full text-sm font-medium text-foreground bg-background border border-input rounded px-2 py-1 focus:outline-none focus:ring-1 focus:ring-ring"
+                            className="w-full text-sm font-medium text-foreground focus:outline-none h-6 border-b border-input"
                           />
                         ) : (
                           <div className="flex items-center gap-2">
                             <Tooltip delayDuration={500}>
                               <TooltipTrigger asChild>
-                                <p className="text-sm font-medium text-foreground truncate flex-1">
+                                <p className="text-sm font-medium text-foreground truncate flex-1 leading-6">
                                   {normalizeTitle(session.title)}
                                 </p>
                               </TooltipTrigger>
@@ -1074,7 +1074,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
 
             {/* Archived Sessions Section */}
             {(onArchiveSession || onUnarchiveSession) && (
-              <div className="mx-2 mb-2 shrink-0 rounded-lg border border-border bg-muted/30">
+              <div className="mx-3 mb-2 shrink-0 rounded-md border border-border bg-muted/30">
                 <Collapsible open={isArchivedExpanded} onOpenChange={setIsArchivedExpanded}>
                   <CollapsibleTrigger className="flex w-full items-center gap-2 px-3 py-2 text-xs text-muted-foreground hover:text-foreground rounded-lg hover:bg-muted/50 group">
                     <ChevronDown className="size-3 transition-transform group-data-[state=closed]:-rotate-90" />
@@ -1092,7 +1092,7 @@ export const SessionsSidebar = memo(function SessionsSidebarComponent({
                     ) : archivedSessions.length === 0 ? (
                       <p className="px-3 py-3 text-xs text-muted-foreground">No archived sessions</p>
                     ) : (
-                      <div className="space-y-1 px-1 pb-2 max-h-[50vh] overflow-y-auto">
+                      <div className="space-y-1 px-1 pb-1 max-h-[50vh] overflow-y-auto">
                         <ul className="space-y-1">
                           {archivedSessions.map((session) => {
                             const isActive = session.id === selectedSessionId;