diff --git a/packages/app/src/components/dialog-select-model.tsx b/packages/app/src/components/dialog-select-model.tsx
index 4f0dcc3ee65e..00e654d8efeb 100644
--- a/packages/app/src/components/dialog-select-model.tsx
+++ b/packages/app/src/components/dialog-select-model.tsx
@@ -90,9 +90,10 @@ const ModelList: Component<{
 
 export function ModelSelectorPopover<T extends ValidComponent = "div">(props: {
   provider?: string
-  children?: JSX.Element
+  children?: JSX.Element | ((open: boolean) => JSX.Element)
   triggerAs?: T
-  triggerProps?: ComponentProps<T>
+  triggerProps?: ComponentProps<T>,
+  gutter?: number
 }) {
   const [store, setStore] = createStore<{
     open: boolean
@@ -175,14 +176,14 @@ export function ModelSelectorPopover<T extends ValidComponent = "div">(props: {
       }}
       modal={false}
       placement="top-start"
-      gutter={8}
+      gutter={props.gutter ?? 8}
     >
       <Kobalte.Trigger
         ref={(el) => setStore("trigger", el)}
         as={props.triggerAs ?? "div"}
         {...(props.triggerProps as any)}
       >
-        {props.children}
+        {typeof props.children === "function" ? props.children(store.open) : props.children}
       </Kobalte.Trigger>
       <Kobalte.Portal>
         <Kobalte.Content
diff --git a/packages/app/src/components/prompt-input.tsx b/packages/app/src/components/prompt-input.tsx
index 5c1d417eb081..0c16bc89350c 100644
--- a/packages/app/src/components/prompt-input.tsx
+++ b/packages/app/src/components/prompt-input.tsx
@@ -32,7 +32,9 @@ import { useNavigate, useParams } from "@solidjs/router"
 import { useSync } from "@/context/sync"
 import { useComments } from "@/context/comments"
 import { FileIcon } from "@opencode-ai/ui/file-icon"
+import { MorphChevron } from "@opencode-ai/ui/morph-chevron"
 import { Button } from "@opencode-ai/ui/button"
+import { CycleLabel } from "@opencode-ai/ui/cycle-label"
 import { Icon } from "@opencode-ai/ui/icon"
 import { ProviderIcon } from "@opencode-ai/ui/provider-icon"
 import type { IconName } from "@opencode-ai/ui/icons/provider"
@@ -42,6 +44,7 @@ import { Select } from "@opencode-ai/ui/select"
 import { getDirectory, getFilename, getFilenameTruncated } from "@opencode-ai/util/path"
 import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { ImagePreview } from "@opencode-ai/ui/image-preview"
+import { ReasoningIcon } from "@opencode-ai/ui/reasoning-icon"
 import { ModelSelectorPopover } from "@/components/dialog-select-model"
 import { DialogSelectModelUnpaid } from "@/components/dialog-select-model-unpaid"
 import { useProviders } from "@/hooks/use-providers"
@@ -922,7 +925,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       .abort({
         sessionID,
       })
-      .catch(() => {})
+      .catch(() => { })
   }
 
   const addToHistory = (prompt: Prompt, mode: "normal" | "shell") => {
@@ -1252,7 +1255,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       clearInput()
       client.session
         .shell({
-          sessionID: session.id,
+          sessionID: session?.id || "",
           agent,
           model,
           command: text,
@@ -1275,7 +1278,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
         clearInput()
         client.session
           .command({
-            sessionID: session.id,
+            sessionID: session?.id || "",
             command: commandName,
             arguments: args.join(" "),
             agent,
@@ -1348,18 +1351,18 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
 
     const contextParts: Array<
       | {
-          id: string
-          type: "text"
-          text: string
-          synthetic?: boolean
-        }
+        id: string
+        type: "text"
+        text: string
+        synthetic?: boolean
+      }
       | {
-          id: string
-          type: "file"
-          mime: string
-          url: string
-          filename?: string
-        }
+        id: string
+        type: "file"
+        mime: string
+        url: string
+        filename?: string
+      }
     > = []
 
     const commentNote = (path: string, selection: FileSelection | undefined, comment: string) => {
@@ -1431,13 +1434,13 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
 
     const optimisticParts = requestParts.map((part) => ({
       ...part,
-      sessionID: session.id,
+      sessionID: session?.id || "",
       messageID,
     })) as unknown as Part[]
 
     const optimisticMessage: Message = {
       id: messageID,
-      sessionID: session.id,
+      sessionID: session?.id || "",
       role: "user",
       time: { created: Date.now() },
       agent,
@@ -1448,9 +1451,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       if (sessionDirectory === projectDirectory) {
         sync.set(
           produce((draft) => {
-            const messages = draft.message[session.id]
+            const messages = draft.message[session?.id || ""]
             if (!messages) {
-              draft.message[session.id] = [optimisticMessage]
+              draft.message[session?.id || ""] = [optimisticMessage]
             } else {
               const result = Binary.search(messages, messageID, (m) => m.id)
               messages.splice(result.index, 0, optimisticMessage)
@@ -1466,9 +1469,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
 
       globalSync.child(sessionDirectory)[1](
         produce((draft) => {
-          const messages = draft.message[session.id]
+          const messages = draft.message[session?.id || ""]
           if (!messages) {
-            draft.message[session.id] = [optimisticMessage]
+            draft.message[session?.id || ""] = [optimisticMessage]
           } else {
             const result = Binary.search(messages, messageID, (m) => m.id)
             messages.splice(result.index, 0, optimisticMessage)
@@ -1485,7 +1488,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       if (sessionDirectory === projectDirectory) {
         sync.set(
           produce((draft) => {
-            const messages = draft.message[session.id]
+            const messages = draft.message[session?.id || ""]
             if (messages) {
               const result = Binary.search(messages, messageID, (m) => m.id)
               if (result.found) messages.splice(result.index, 1)
@@ -1498,7 +1501,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
 
       globalSync.child(sessionDirectory)[1](
         produce((draft) => {
-          const messages = draft.message[session.id]
+          const messages = draft.message[session?.id || ""]
           if (messages) {
             const result = Binary.search(messages, messageID, (m) => m.id)
             if (result.found) messages.splice(result.index, 1)
@@ -1519,15 +1522,15 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       const worktree = WorktreeState.get(sessionDirectory)
       if (!worktree || worktree.status !== "pending") return true
 
-      if (sessionDirectory === projectDirectory) {
-        sync.set("session_status", session.id, { type: "busy" })
+      if (sessionDirectory === projectDirectory && session?.id) {
+        sync.set("session_status", session?.id, { type: "busy" })
       }
 
       const controller = new AbortController()
 
       const cleanup = () => {
-        if (sessionDirectory === projectDirectory) {
-          sync.set("session_status", session.id, { type: "idle" })
+        if (sessionDirectory === projectDirectory && session?.id) {
+          sync.set("session_status", session?.id, { type: "idle" })
         }
         removeOptimisticMessage()
         for (const item of commentItems) {
@@ -1544,7 +1547,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
         restoreInput()
       }
 
-      pending.set(session.id, { abort: controller, cleanup })
+      pending.set(session?.id || "", { abort: controller, cleanup })
 
       const abort = new Promise<Awaited<ReturnType<typeof WorktreeState.wait>>>((resolve) => {
         if (controller.signal.aborted) {
@@ -1572,7 +1575,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
         if (timer.id === undefined) return
         clearTimeout(timer.id)
       })
-      pending.delete(session.id)
+      pending.delete(session?.id || "")
       if (controller.signal.aborted) return false
       if (result.status === "failed") throw new Error(result.message)
       return true
@@ -1582,7 +1585,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       const ok = await waitForWorktree()
       if (!ok) return
       await client.session.prompt({
-        sessionID: session.id,
+        sessionID: session?.id || "",
         agent,
         model,
         messageID,
@@ -1592,9 +1595,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
     }
 
     void send().catch((err) => {
-      pending.delete(session.id)
-      if (sessionDirectory === projectDirectory) {
-        sync.set("session_status", session.id, { type: "idle" })
+      pending.delete(session?.id || "")
+      if (sessionDirectory === projectDirectory && session?.id) {
+        sync.set("session_status", session?.id, { type: "idle" })
       }
       showToast({
         title: language.t("prompt.toast.promptSendFailed.title"),
@@ -1616,6 +1619,28 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
     })
   }
 
+  const currrentModelVariant = createMemo(() => {
+    const modelVariant = local.model.variant.current() ?? ""
+    return modelVariant === "xhigh"
+      ? "xHigh"
+      : modelVariant.length > 0
+        ? modelVariant[0].toUpperCase() + modelVariant.slice(1)
+        : "Default"
+  })
+
+  const reasoningPercentage = createMemo(() => {
+    const variants = local.model.variant.list()
+    const current = local.model.variant.current()
+    const totalEntries = variants.length + 1
+
+    if (totalEntries <= 2 || current === "Default") {
+      return 0
+    }
+
+    const currentIndex = current ? variants.indexOf(current) + 1 : 0
+    return ((currentIndex + 1) / totalEntries) * 100
+  }, [local.model.variant])
+
   return (
     <div class="relative size-full _max-h-[320px] flex flex-col gap-3">
       <Show when={store.popover}>
@@ -1668,7 +1693,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                           </>
                         }
                       >
-                        <Icon name="brain" size="small" class="text-icon-info-active shrink-0" />
+                        <Icon name="brain" size="normal" class="text-icon-info-active shrink-0" />
                         <span class="text-14-regular text-text-strong whitespace-nowrap">
                           @{(item as { type: "agent"; name: string }).name}
                         </span>
@@ -1729,9 +1754,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
         }}
       >
         <Show when={store.dragging}>
-          <div class="absolute inset-0 z-10 flex items-center justify-center bg-surface-raised-stronger-non-alpha/90 pointer-events-none">
+          <div class="absolute inset-0 z-10 flex items-center justify-center bg-surface-raised-stronger-non-alpha/90 mr-1 pointer-events-none">
             <div class="flex flex-col items-center gap-2 text-text-weak">
-              <Icon name="photo" class="size-8" />
+              <Icon name="photo" size={18} class="text-icon-base stroke-1.5" />
               <span class="text-14-regular">{language.t("prompt.dropzone.label")}</span>
             </div>
           </div>
@@ -1770,7 +1795,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                       }}
                     >
                       <div class="flex items-center gap-1.5">
-                        <FileIcon node={{ path: item.path, type: "file" }} class="shrink-0 size-3.5" />
+                        <FileIcon node={{ path: item.path, type: "file" }} class="shrink-0 size-7" />
                         <div class="flex items-center text-11-regular min-w-0 font-medium">
                           <span class="text-text-strong whitespace-nowrap">{getFilenameTruncated(item.path, 14)}</span>
                           <Show when={item.selection}>
@@ -1787,7 +1812,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                           type="button"
                           icon="close-small"
                           variant="ghost"
-                          class="ml-auto h-5 w-5 opacity-0 group-hover:opacity-100 transition-all"
+                          class="ml-auto size-7 opacity-0 group-hover:opacity-100 transition-all"
                           onClick={(e) => {
                             e.stopPropagation()
                             if (item.commentID) comments.remove(item.path, item.commentID)
@@ -1817,7 +1842,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                     when={attachment.mime.startsWith("image/")}
                     fallback={
                       <div class="size-16 rounded-md bg-surface-base flex items-center justify-center border border-border-base">
-                        <Icon name="folder" class="size-6 text-text-weak" />
+                        <Icon name="folder" size="normal" class="size-6 text-text-base" />
                       </div>
                     }
                   >
@@ -1891,7 +1916,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
           </Show>
         </div>
         <div class="relative p-3 flex items-center justify-between">
-          <div class="flex items-center justify-start gap-0.5">
+          <div class="flex items-center justify-start gap-2">
             <Switch>
               <Match when={store.mode === "shell"}>
                 <div class="flex items-center gap-2 px-2 h-6">
@@ -1912,6 +1937,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                     onSelect={local.agent.set}
                     class="capitalize"
                     variant="ghost"
+                    gutter={12}
                   />
                 </TooltipKeybind>
                 <Show
@@ -1922,12 +1948,17 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                       title={language.t("command.model.choose")}
                       keybind={command.keybind("model.choose")}
                     >
-                      <Button as="div" variant="ghost" onClick={() => dialog.show(() => <DialogSelectModelUnpaid />)}>
+                      <Button
+                        as="div"
+                        variant="ghost"
+                        class="px-2"
+                        onClick={() => dialog.show(() => <DialogSelectModelUnpaid />)}
+                      >
                         <Show when={local.model.current()?.provider?.id}>
                           <ProviderIcon id={local.model.current()!.provider.id as IconName} class="size-4 shrink-0" />
                         </Show>
                         {local.model.current()?.name ?? language.t("dialog.model.select.title")}
-                        <Icon name="chevron-down" size="small" />
+                        <MorphChevron expanded={!!dialog.active?.id && dialog.active.id.startsWith("select-model-unpaid")} />
                       </Button>
                     </TooltipKeybind>
                   }
@@ -1937,12 +1968,16 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                     title={language.t("command.model.choose")}
                     keybind={command.keybind("model.choose")}
                   >
-                    <ModelSelectorPopover triggerAs={Button} triggerProps={{ variant: "ghost" }}>
-                      <Show when={local.model.current()?.provider?.id}>
-                        <ProviderIcon id={local.model.current()!.provider.id as IconName} class="size-4 shrink-0" />
-                      </Show>
-                      {local.model.current()?.name ?? language.t("dialog.model.select.title")}
-                      <Icon name="chevron-down" size="small" />
+                    <ModelSelectorPopover triggerAs={Button} triggerProps={{ variant: "ghost" }} gutter={12}>
+                      {(open) => (
+                        <>
+                          <Show when={local.model.current()?.provider?.id}>
+                            <ProviderIcon id={local.model.current()!.provider.id as IconName} class="size-4 shrink-0" />
+                          </Show>
+                          {local.model.current()?.name ?? language.t("dialog.model.select.title")}
+                          <MorphChevron expanded={open} class="text-text-weak" />
+                        </>
+                      )}
                     </ModelSelectorPopover>
                   </TooltipKeybind>
                 </Show>
@@ -1955,10 +1990,13 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                     <Button
                       data-action="model-variant-cycle"
                       variant="ghost"
-                      class="text-text-base _hidden group-hover/prompt-input:inline-block capitalize text-12-regular"
+                      class="text-text-strong text-12-regular"
                       onClick={() => local.model.variant.cycle()}
                     >
-                      {local.model.variant.current() ?? language.t("common.default")}
+                      <Show when={local.model.variant.list().length > 1}>
+                        <ReasoningIcon percentage={reasoningPercentage()} size={16} strokeWidth={1.25} />
+                      </Show>
+                      <CycleLabel value={currrentModelVariant()} />
                     </Button>
                   </TooltipKeybind>
                 </Show>
@@ -1972,7 +2010,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                       variant="ghost"
                       onClick={() => permission.toggleAutoAccept(params.id!, sdk.directory)}
                       classList={{
-                        "_hidden group-hover/prompt-input:flex size-6 items-center justify-center": true,
+                        "_hidden group-hover/prompt-input:flex items-center justify-center": true,
                         "text-text-base": !permission.isAutoAccepting(params.id!, sdk.directory),
                         "hover:bg-surface-success-base": permission.isAutoAccepting(params.id!, sdk.directory),
                       }}
@@ -1994,7 +2032,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
               </Match>
             </Switch>
           </div>
-          <div class="flex items-center gap-3 absolute right-3 bottom-3">
+          <div class="flex items-center gap-1 absolute right-3 bottom-3">
             <input
               ref={fileInputRef}
               type="file"
@@ -2006,18 +2044,19 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                 e.currentTarget.value = ""
               }}
             />
-            <div class="flex items-center gap-2">
+            <div class="flex items-center gap-1.5 mr-1.5">
               <SessionContextUsage />
               <Show when={store.mode === "normal"}>
                 <Tooltip placement="top" value={language.t("prompt.action.attachFile")}>
                   <Button
                     type="button"
                     variant="ghost"
-                    class="size-6"
+                    size="small"
+                    class="px-1"
                     onClick={() => fileInputRef.click()}
                     aria-label={language.t("prompt.action.attachFile")}
                   >
-                    <Icon name="photo" class="size-4.5" />
+                    <Icon name="photo" class="size-6 text-icon-base" />
                   </Button>
                 </Tooltip>
               </Show>
@@ -2036,7 +2075,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                   <Match when={true}>
                     <div class="flex items-center gap-2">
                       <span>{language.t("prompt.action.send")}</span>
-                      <Icon name="enter" size="small" class="text-icon-base" />
+                      <Icon name="enter" size="normal" class="text-icon-base" />
                     </div>
                   </Match>
                 </Switch>
@@ -2047,7 +2086,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                 disabled={!prompt.dirty() && !working()}
                 icon={working() ? "stop" : "arrow-up"}
                 variant="primary"
-                class="h-6 w-4.5"
+                class="h-6 w-5.5"
                 aria-label={working() ? language.t("prompt.action.stop") : language.t("prompt.action.send")}
               />
             </Tooltip>
@@ -2162,4 +2201,4 @@ function setCursorPosition(parent: HTMLElement, position: number) {
   fallbackRange.collapse(false)
   fallbackSelection?.removeAllRanges()
   fallbackSelection?.addRange(fallbackRange)
-}
+}
\ No newline at end of file
diff --git a/packages/app/src/components/settings-general.tsx b/packages/app/src/components/settings-general.tsx
index b31cfb6cc794..e43b82e4a8e6 100644
--- a/packages/app/src/components/settings-general.tsx
+++ b/packages/app/src/components/settings-general.tsx
@@ -60,24 +60,24 @@ export const SettingsGeneral: Component = () => {
         const actions =
           platform.update && platform.restart
             ? [
-                {
-                  label: language.t("toast.update.action.installRestart"),
-                  onClick: async () => {
-                    await platform.update!()
-                    await platform.restart!()
-                  },
+              {
+                label: language.t("toast.update.action.installRestart"),
+                onClick: async () => {
+                  await platform.update!()
+                  await platform.restart!()
                 },
-                {
-                  label: language.t("toast.update.action.notYet"),
-                  onClick: "dismiss" as const,
-                },
-              ]
+              },
+              {
+                label: language.t("toast.update.action.notYet"),
+                onClick: "dismiss" as const,
+              },
+            ]
             : [
-                {
-                  label: language.t("toast.update.action.notYet"),
-                  onClick: "dismiss" as const,
-                },
-              ]
+              {
+                label: language.t("toast.update.action.notYet"),
+                onClick: "dismiss" as const,
+              },
+            ]
 
         showToast({
           persistent: true,
@@ -226,7 +226,7 @@ export const SettingsGeneral: Component = () => {
                 variant="secondary"
                 size="small"
                 triggerVariant="settings"
-                triggerStyle={{ "font-family": monoFontFamily(settings.appearance.font()), "min-width": "180px" }}
+                triggerStyle={{ "font-family": monoFontFamily(settings.appearance.font()), "field-sizing": "content" }}
               >
                 {(option) => (
                   <span style={{ "font-family": monoFontFamily(option?.value) }}>
diff --git a/packages/ui/src/components/button.css b/packages/ui/src/components/button.css
index d9b345923047..3e5d21d1de81 100644
--- a/packages/ui/src/components/button.css
+++ b/packages/ui/src/components/button.css
@@ -9,7 +9,13 @@
   user-select: none;
   cursor: default;
   outline: none;
+  padding: 4px 8px;
   white-space: nowrap;
+  transition-property: background-color, border-color, color, box-shadow, opacity;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+  outline: none;
+  line-height: 20px;
 
   &[data-variant="primary"] {
     background-color: var(--button-primary-base);
@@ -94,7 +100,6 @@
     &:active:not(:disabled) {
       background-color: var(--button-secondary-base);
       scale: 0.99;
-      transition: all 150ms ease-out;
     }
     &:disabled {
       border-color: var(--border-disabled);
@@ -109,34 +114,31 @@
   }
 
   &[data-size="small"] {
-    height: 22px;
-    padding: 0 8px;
+    padding: 4px 8px;
     &[data-icon] {
-      padding: 0 12px 0 4px;
+      padding: 4px 12px 4px 4px;
     }
 
-    font-size: var(--font-size-small);
-    line-height: var(--line-height-large);
     gap: 4px;
 
     /* text-12-medium */
     font-family: var(--font-family-sans);
-    font-size: var(--font-size-small);
+    font-size: var(--font-size-base);
     font-style: normal;
     font-weight: var(--font-weight-medium);
-    line-height: var(--line-height-large); /* 166.667% */
     letter-spacing: var(--letter-spacing-normal);
   }
 
   &[data-size="normal"] {
-    height: 24px;
-    line-height: 24px;
-    padding: 0 6px;
+    padding: 4px 6px;
     &[data-icon] {
-      padding: 0 12px 0 4px;
+      padding: 4px 12px 4px 4px;
+    }
+
+    &[aria-haspopup] {
+      padding: 4px 6px 4px 8px;
     }
 
-    font-size: var(--font-size-small);
     gap: 6px;
 
     /* text-12-medium */
@@ -148,7 +150,6 @@
   }
 
   &[data-size="large"] {
-    height: 32px;
     padding: 6px 12px;
 
     &[data-icon] {
diff --git a/packages/ui/src/components/button.tsx b/packages/ui/src/components/button.tsx
index 7f974b2f76e7..1b110ca8afce 100644
--- a/packages/ui/src/components/button.tsx
+++ b/packages/ui/src/components/button.tsx
@@ -4,7 +4,7 @@ import { Icon, IconProps } from "./icon"
 
 export interface ButtonProps
   extends ComponentProps<typeof Kobalte>,
-    Pick<ComponentProps<"button">, "class" | "classList" | "children"> {
+  Pick<ComponentProps<"button">, "class" | "classList" | "children" | "style"> {
   size?: "small" | "normal" | "large"
   variant?: "primary" | "secondary" | "ghost"
   icon?: IconProps["name"]
diff --git a/packages/ui/src/components/cycle-label.css b/packages/ui/src/components/cycle-label.css
new file mode 100644
index 000000000000..3c98fcd261eb
--- /dev/null
+++ b/packages/ui/src/components/cycle-label.css
@@ -0,0 +1,49 @@
+.cycle-label {
+  --c-duration: 200ms;
+  --c-stagger: 30ms;
+  --c-opacity-start: 0;
+  --c-opacity-end: 1;
+  --c-blur-start: 0px;
+  --c-blur-end: 0px;
+  --c-skew: 10deg;
+
+  display: inline-flex;
+  position: relative;
+
+  transform-style: preserve-3d;
+  perspective: 500px;
+  transition: width var(--transition-duration) var(--transition-easing);
+  will-change: width;
+  overflow: hidden;
+
+  .cycle-char {
+    display: inline-block;
+    transform-style: preserve-3d;
+    min-width: 0.25em;
+    backface-visibility: hidden;
+
+    transition-property: transform, opacity, filter;
+    transition-duration: var(--transition-duration);
+    transition-timing-function: var(--transition-easing);
+    transition-delay: calc(var(--i, 0) * var(--c-stagger));
+
+    &.enter {
+      opacity: var(--c-opacity-end);
+      filter: blur(var(--c-blur-end));
+      transform: translateY(0) rotateX(0) skewX(0);
+    }
+
+    &.exit {
+      opacity: var(--c-opacity-start);
+      filter: blur(var(--c-blur-start));
+      transform: translateY(50%) rotateX(90deg) skewX(var(--c-skew));
+    }
+
+    &.pre {
+      opacity: var(--c-opacity-start);
+      filter: blur(var(--c-blur-start));
+      transition: none;
+      transform: translateY(-50%) rotateX(-90deg) skewX(calc(var(--c-skew) * -1));
+    }
+  }
+}
diff --git a/packages/ui/src/components/cycle-label.tsx b/packages/ui/src/components/cycle-label.tsx
new file mode 100644
index 000000000000..f1eaa88f31c4
--- /dev/null
+++ b/packages/ui/src/components/cycle-label.tsx
@@ -0,0 +1,132 @@
+import "./cycle-label.css"
+import { createEffect, createSignal, JSX, on } from "solid-js"
+
+export interface CycleLabelProps extends JSX.HTMLAttributes<HTMLSpanElement> {
+  value: string
+  onValueChange?: (value: string) => void
+  duration?: number | ((value: string) => number)
+  stagger?: number
+  opacity?: [number, number]
+  blur?: [number, number]
+  skewX?: number
+  onAnimationStart?: () => void
+  onAnimationEnd?: () => void
+}
+
+const segmenter =
+  typeof Intl !== "undefined" && Intl.Segmenter ? new Intl.Segmenter("en", { granularity: "grapheme" }) : null
+
+const getChars = (text: string): string[] =>
+  segmenter ? Array.from(segmenter.segment(text), (s) => s.segment) : text.split("")
+
+const wait = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms))
+
+export function CycleLabel(props: CycleLabelProps) {
+  const getDuration = (text: string) => {
+    const d = props.duration ?? Number(getComputedStyle(document.documentElement).getPropertyValue("--transition-duration")) ?? 200
+    return typeof d === "function" ? d(text) : d
+  }
+  const stagger = () => props?.stagger ?? 30
+  const opacity = () => props?.opacity ?? [0, 1]
+  const blur = () => props?.blur ?? [0, 0]
+  const skewX = () => props?.skewX ?? 10
+
+  let containerRef: HTMLSpanElement | undefined
+  let isAnimating = false
+  const [currentText, setCurrentText] = createSignal(props.value)
+
+  const setChars = (el: HTMLElement, text: string, state: "enter" | "exit" | "pre" = "enter") => {
+    el.innerHTML = ""
+    const chars = getChars(text)
+    chars.forEach((char, i) => {
+      const span = document.createElement("span")
+      span.textContent = char === " " ? "\u00A0" : char
+      span.className = `cycle-char ${state}`
+      span.style.setProperty("--i", String(i))
+      el.appendChild(span)
+    })
+  }
+
+  const animateToText = async (newText: string) => {
+    if (!containerRef || isAnimating) return
+    if (newText === currentText()) return
+
+    isAnimating = true
+    props.onAnimationStart?.()
+
+    const dur = getDuration(newText)
+    const stag = stagger()
+
+    containerRef.style.width = containerRef.offsetWidth + "px"
+
+    const oldChars = containerRef.querySelectorAll(".cycle-char")
+    oldChars.forEach((c) => c.classList.replace("enter", "exit"))
+
+    const clone = containerRef.cloneNode(false) as HTMLElement
+    Object.assign(clone.style, {
+      position: "absolute",
+      visibility: "hidden",
+      width: "auto",
+      transition: "none",
+    })
+    setChars(clone, newText)
+    document.body.appendChild(clone)
+    const nextWidth = clone.offsetWidth
+    clone.remove()
+
+    const exitTime = oldChars.length * stag + dur
+    await wait(exitTime * 0.3)
+
+    containerRef.style.width = nextWidth + "px"
+
+    const widthDur = 200
+    await wait(widthDur * 0.3)
+
+    setChars(containerRef, newText, "pre")
+    containerRef.offsetWidth
+
+    Array.from(containerRef.children).forEach((c) => (c.className = "cycle-char enter"))
+    setCurrentText(newText)
+    props.onValueChange?.(newText)
+
+    const enterTime = getChars(newText).length * stag + dur
+    await wait(enterTime)
+
+    containerRef.style.width = ""
+    isAnimating = false
+    props.onAnimationEnd?.()
+  }
+
+  createEffect(
+    on(
+      () => props.value,
+      (newValue) => {
+        if (newValue !== currentText()) {
+          animateToText(newValue)
+        }
+      },
+    ),
+  )
+
+  const initRef = (el: HTMLSpanElement) => {
+    containerRef = el
+    setChars(el, props.value)
+  }
+
+  return (
+    <span
+      ref={initRef}
+      class={`cycle-label ${props.class ?? ""}`}
+      style={{
+        "--c-duration": `${getDuration(currentText())}ms`,
+        "--c-stagger": `${stagger()}ms`,
+        "--c-opacity-start": opacity()[0],
+        "--c-opacity-end": opacity()[1],
+        "--c-blur-start": `${blur()[0]}px`,
+        "--c-blur-end": `${blur()[1]}px`,
+        "--c-skew": `${skewX()}deg`,
+        ...(typeof props.style === "object" ? props.style : {}),
+      }}
+    />
+  )
+}
\ No newline at end of file
diff --git a/packages/ui/src/components/dropdown-menu.css b/packages/ui/src/components/dropdown-menu.css
index cba041613eab..18266ac1a1c7 100644
--- a/packages/ui/src/components/dropdown-menu.css
+++ b/packages/ui/src/components/dropdown-menu.css
@@ -2,26 +2,29 @@
 [data-component="dropdown-menu-sub-content"] {
   min-width: 8rem;
   overflow: hidden;
+  border: none;
   border-radius: var(--radius-md);
-  border: 1px solid color-mix(in oklch, var(--border-base) 50%, transparent);
+  box-shadow: var(--shadow-xs-border);
   background-clip: padding-box;
   background-color: var(--surface-raised-stronger-non-alpha);
   padding: 4px;
-  box-shadow: var(--shadow-md);
-  z-index: 50;
+  z-index: 100;
   transform-origin: var(--kb-menu-content-transform-origin);
 
-  &:focus,
-  &:focus-visible {
+  &:focus-within,
+  &:focus {
     outline: none;
   }
 
-  &[data-closed] {
-    animation: dropdown-menu-close 0.15s ease-out;
+  animation: dropdownMenuContentHide var(--transition-duration) var(--transition-easing) forwards;
+
+  @starting-style {
+    animation: none;
   }
 
   &[data-expanded] {
-    animation: dropdown-menu-open 0.15s ease-out;
+    pointer-events: auto;
+    animation: dropdownMenuContentShow var(--transition-duration) var(--transition-easing) forwards;
   }
 }
 
@@ -38,18 +41,22 @@
     padding: 4px 8px;
     border-radius: var(--radius-sm);
     cursor: default;
-    user-select: none;
     outline: none;
 
     font-family: var(--font-family-sans);
-    font-size: var(--font-size-small);
+    font-size: var(--font-size-base);
     font-weight: var(--font-weight-medium);
     line-height: var(--line-height-large);
     letter-spacing: var(--letter-spacing-normal);
     color: var(--text-strong);
 
-    &[data-highlighted] {
-      background: var(--surface-raised-base-hover);
+    transition-property: background-color, color;
+    transition-duration: var(--transition-duration);
+    transition-timing-function: var(--transition-easing);
+    user-select: none;
+
+    &:hover {
+      background-color: var(--surface-raised-base-hover);
     }
 
     &[data-disabled] {
@@ -61,6 +68,8 @@
   [data-slot="dropdown-menu-sub-trigger"] {
     &[data-expanded] {
       background: var(--surface-raised-base-hover);
+      outline: none;
+      border: none;
     }
   }
 
@@ -102,24 +111,24 @@
   }
 }
 
-@keyframes dropdown-menu-open {
+@keyframes dropdownMenuContentShow {
   from {
     opacity: 0;
-    transform: scale(0.96);
+    transform: scaleY(0.95);
   }
   to {
     opacity: 1;
-    transform: scale(1);
+    transform: scaleY(1);
   }
 }
 
-@keyframes dropdown-menu-close {
+@keyframes dropdownMenuContentHide {
   from {
     opacity: 1;
-    transform: scale(1);
+    transform: scaleY(1);
   }
   to {
     opacity: 0;
-    transform: scale(0.96);
+    transform: scaleY(0.95);
   }
 }
diff --git a/packages/ui/src/components/icon.tsx b/packages/ui/src/components/icon.tsx
index 544c6abdd214..f23357293ee6 100644
--- a/packages/ui/src/components/icon.tsx
+++ b/packages/ui/src/components/icon.tsx
@@ -80,13 +80,13 @@ const icons = {
 
 export interface IconProps extends ComponentProps<"svg"> {
   name: keyof typeof icons
-  size?: "small" | "normal" | "medium" | "large"
+  size?: "small" | "normal" | "medium" | "large" | number
 }
 
 export function Icon(props: IconProps) {
   const [local, others] = splitProps(props, ["name", "size", "class", "classList"])
   return (
-    <div data-component="icon" data-size={local.size || "normal"}>
+    <div data-component="icon" data-size={typeof local.size !== 'number' ? local.size || "normal" : `size-[${local.size}px]`}>
       <svg
         data-slot="icon-svg"
         classList={{
diff --git a/packages/ui/src/components/message-part.tsx b/packages/ui/src/components/message-part.tsx
index 7aad01acea38..b8a7ce0b505f 100644
--- a/packages/ui/src/components/message-part.tsx
+++ b/packages/ui/src/components/message-part.tsx
@@ -42,13 +42,13 @@ import { Checkbox } from "./checkbox"
 import { DiffChanges } from "./diff-changes"
 import { Markdown } from "./markdown"
 import { ImagePreview } from "./image-preview"
-import { findLast } from "@opencode-ai/util/array"
 import { getDirectory as _getDirectory, getFilename } from "@opencode-ai/util/path"
 import { checksum } from "@opencode-ai/util/encode"
 import { Tooltip } from "./tooltip"
 import { IconButton } from "./icon-button"
 import { createAutoScroll } from "../hooks"
 import { createResizeObserver } from "@solid-primitives/resize-observer"
+import { MorphChevron } from "./morph-chevron"
 
 interface Diagnostic {
   range: {
@@ -415,7 +415,7 @@ export function UserMessageDisplay(props: { message: UserMessage; parts: PartTyp
               toggleExpanded()
             }}
           >
-            <Icon name="chevron-down" size="small" />
+            <MorphChevron expanded={expanded()} />
           </button>
           <div data-slot="user-message-copy-wrapper">
             <Tooltip
@@ -898,7 +898,7 @@ ToolRegistry.register({
       if (!sessionId) return undefined
       // Find the tool part that matches the permission's callID
       const messages = data.store.message[sessionId] ?? []
-      const message = findLast(messages, (m) => m.id === perm.tool!.messageID)
+      const message = messages.findLast((m) => m.id === perm.tool!.messageID)
       if (!message) return undefined
       const parts = data.store.part[message.id] ?? []
       for (const part of parts) {
diff --git a/packages/ui/src/components/morph-chevron.css b/packages/ui/src/components/morph-chevron.css
new file mode 100644
index 000000000000..f6edb3f649ac
--- /dev/null
+++ b/packages/ui/src/components/morph-chevron.css
@@ -0,0 +1,10 @@
+[data-slot="morph-chevron-svg"] {
+  width: 16px;
+  height: 16px;
+  display: block;
+  fill: none;
+  stroke-width: 1.5;
+  stroke: currentcolor;
+  stroke-linecap: round;
+  stroke-linejoin: round;
+}
diff --git a/packages/ui/src/components/morph-chevron.tsx b/packages/ui/src/components/morph-chevron.tsx
new file mode 100644
index 000000000000..a14a2252b6ad
--- /dev/null
+++ b/packages/ui/src/components/morph-chevron.tsx
@@ -0,0 +1,73 @@
+import { createEffect, createUniqueId, on } from "solid-js"
+
+export interface MorphChevronProps {
+  expanded: boolean
+  class?: string
+}
+
+const COLLAPSED = "M4 6L8 10L12 6"
+const EXPANDED = "M4 10L8 6L12 10"
+
+export function MorphChevron(props: MorphChevronProps) {
+  const id = createUniqueId()
+  let path: SVGPathElement | undefined
+  let expandAnim: SVGAnimateElement | undefined
+  let collapseAnim: SVGAnimateElement | undefined
+
+  createEffect(
+    on(
+      () => props.expanded,
+      (expanded, prev) => {
+        if (prev === undefined) {
+          // Set initial state without animation
+          path?.setAttribute("d", expanded ? EXPANDED : COLLAPSED)
+          return
+        }
+        if (expanded) {
+          expandAnim?.beginElement()
+        } else {
+          collapseAnim?.beginElement()
+        }
+      },
+    ),
+  )
+
+  return (
+    <svg
+      viewBox="0 0 16 16"
+      data-slot="morph-chevron-svg"
+      class={props.class}
+      xmlns="http://www.w3.org/2000/svg"
+      aria-hidden="true"
+    >
+      <path ref={path} d={COLLAPSED} id={`morph-chevron-path-${id}`}>
+        <animate
+          ref={(el) => {
+            expandAnim = el
+          }}
+          id={`morph-expand-${id}`}
+          attributeName="d"
+          dur="200ms"
+          fill="freeze"
+          calcMode="spline"
+          keySplines="0.25 0 0.5 1"
+          values="M4 6L8 10L12 6;M4 10L8 6L12 10"
+          begin="indefinite"
+        />
+        <animate
+          ref={(el) => {
+            collapseAnim = el
+          }}
+          id={`morph-collapse-${id}`}
+          attributeName="d"
+          dur="200ms"
+          fill="freeze"
+          calcMode="spline"
+          keySplines="0.25 0 0.5 1"
+          values="M4 10L8 6L12 10;M4 6L8 10L12 6"
+          begin="indefinite"
+        />
+      </path>
+    </svg>
+  )
+}
\ No newline at end of file
diff --git a/packages/ui/src/components/popover.css b/packages/ui/src/components/popover.css
index b49542afd9b8..d200fe8b2476 100644
--- a/packages/ui/src/components/popover.css
+++ b/packages/ui/src/components/popover.css
@@ -15,16 +15,35 @@
 
   transform-origin: var(--kb-popover-content-transform-origin);
 
-  &:focus-within {
-    outline: none;
-  }
+  animation: popoverContentHide var(--transition-duration) var(--transition-easing) forwards;
 
-  &[data-closed] {
-    animation: popover-close 0.15s ease-out;
+  @starting-style {
+    animation: none;
   }
 
   &[data-expanded] {
-    animation: popover-open 0.15s ease-out;
+    pointer-events: auto;
+    animation: popoverContentShow var(--transition-duration) var(--transition-easing) forwards;
+  }
+
+  [data-origin-top-right] {
+    transform-origin: top right;
+  }
+
+  [data-origin-top-left] {
+    transform-origin: top left;
+  }
+
+  [data-origin-bottom-right] {
+    transform-origin: bottom right;
+  }
+
+  [data-origin-bottom-left] {
+    transform-origin: bottom left;
+  }
+
+  &:focus-within {
+    outline: none;
   }
 
   [data-slot="popover-header"] {
@@ -75,24 +94,39 @@
   }
 }
 
-@keyframes popover-open {
+@keyframes popoverContentShow {
   from {
     opacity: 0;
-    transform: scale(0.96);
+    transform: scaleY(0.95);
   }
   to {
     opacity: 1;
-    transform: scale(1);
+    transform: scaleY(1);
   }
 }
 
-@keyframes popover-close {
+@keyframes popoverContentHide {
   from {
     opacity: 1;
-    transform: scale(1);
+    transform: scaleY(1);
   }
   to {
     opacity: 0;
-    transform: scale(0.96);
+    transform: scaleY(0.95);
+  }
+}
+
+[data-component="model-popover-content"] {
+  transform-origin: var(--kb-popper-content-transform-origin);
+  pointer-events: none;
+  animation: popoverContentHide var(--transition-duration) var(--transition-easing) forwards;
+
+  @starting-style {
+    animation: none;
+  }
+
+  &[data-expanded] {
+    pointer-events: auto;
+    animation: popoverContentShow var(--transition-duration) var(--transition-easing) forwards;
   }
 }
diff --git a/packages/ui/src/components/reasoning-icon.css b/packages/ui/src/components/reasoning-icon.css
new file mode 100644
index 000000000000..26fbc0144896
--- /dev/null
+++ b/packages/ui/src/components/reasoning-icon.css
@@ -0,0 +1,9 @@
+[data-component="reasoning-icon"] {
+  color: var(--icon-strong-base);
+
+  [data-slot="reasoning-icon-percentage"] {
+    transition: clip-path 200ms cubic-bezier(0.25, 0, 0.5, 1);
+    clip-path: inset(calc(100% - var(--reasoning-icon-percentage) * 100%) 0 0 0);
+    opacity: calc(var(--reasoning-icon-percentage) * 0.75);
+  }
+}
diff --git a/packages/ui/src/components/reasoning-icon.tsx b/packages/ui/src/components/reasoning-icon.tsx
new file mode 100644
index 000000000000..ba753b3b843d
--- /dev/null
+++ b/packages/ui/src/components/reasoning-icon.tsx
@@ -0,0 +1,32 @@
+import { type ComponentProps, splitProps } from "solid-js"
+
+export interface ReasoningIconProps extends Pick<ComponentProps<"svg">, "class" | "classList"> {
+  percentage: number
+  size?: number
+  strokeWidth?: number
+}
+
+export function ReasoningIcon(props: ReasoningIconProps) {
+  const [split, rest] = splitProps(props, ["percentage", "size", "strokeWidth", "class", "classList"])
+
+  const size = () => split.size || 16
+  const strokeWidth = () => split.strokeWidth || 1.25
+
+  return (
+    <svg
+      {...rest}
+      width={size()}
+      height={size()}
+      viewBox={`0 0 16 16`}
+      fill="none"
+      data-component="reasoning-icon"
+      classList={{
+        ...(split.classList ?? {}),
+        [split.class ?? ""]: !!split.class,
+      }}
+    >
+      <path d="M5.83196 10.3225V11.1666C5.83196 11.7189 6.27967 12.1666 6.83196 12.1666H9.16687C9.71915 12.1666 10.1669 11.7189 10.1669 11.1666V10.3225M5.83196 10.3225C5.55695 10.1843 5.29695 10.0206 5.05505 9.83459C3.90601 8.95086 3.16549 7.56219 3.16549 6.00055C3.16549 3.33085 5.32971 1.16663 7.99941 1.16663C10.6691 1.16663 12.8333 3.33085 12.8333 6.00055C12.8333 7.56219 12.0928 8.95086 10.9438 9.83459C10.7019 10.0206 10.4419 10.1843 10.1669 10.3225M5.83196 10.3225H10.1669M6.5 14.1666H9.5" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" />
+      <circle cx="8" cy="5.83325" r="2.86364" fill="currentColor" stroke="currentColor" stroke-width={strokeWidth()} style={{ '--reasoning-icon-percentage': split.percentage / 100 }} data-slot="reasoning-icon-percentage" />
+    </svg>
+  )
+}
\ No newline at end of file
diff --git a/packages/ui/src/components/select.css b/packages/ui/src/components/select.css
index 25dd2eb40b67..eaba6fd6d2a1 100644
--- a/packages/ui/src/components/select.css
+++ b/packages/ui/src/components/select.css
@@ -1,7 +1,13 @@
 [data-component="select"] {
   [data-slot="select-select-trigger"] {
-    padding: 0 4px 0 8px;
+    display: flex;
+    padding: 4px 8px !important;
+    align-items: center;
+    justify-content: space-between;
     box-shadow: none;
+    transition-property: background-color;
+    transition-duration: var(--transition-duration);
+    transition-timing-function: var(--transition-easing);
 
     [data-slot="select-select-trigger-value"] {
       overflow: hidden;
@@ -15,10 +21,10 @@
       align-items: center;
       justify-content: center;
       flex-shrink: 0;
-      color: var(--text-weak);
-      transition: transform 0.1s ease-in-out;
+      color: var(--icon-base);
     }
 
+    &:hover,
     &[data-expanded] {
       &[data-variant="secondary"] {
         background-color: var(--button-secondary-hover);
@@ -30,13 +36,13 @@
         background-color: var(--icon-strong-active);
       }
     }
-
+    &:not([data-expanded]):focus,
     &:not([data-expanded]):focus-visible {
       &[data-variant="secondary"] {
         background-color: var(--button-secondary-base);
       }
       &[data-variant="ghost"] {
-        background-color: var(--surface-raised-base-hover);
+        background-color: transparent;
       }
       &[data-variant="primary"] {
         background-color: var(--icon-strong-base);
@@ -46,10 +52,10 @@
 
   &[data-trigger-style="settings"] {
     [data-slot="select-select-trigger"] {
-      padding: 6px 6px 6px 12px;
+      padding: 6px 6px 6px 10px;
       box-shadow: none;
       border-radius: 6px;
-      min-width: 160px;
+      field-sizing: content;
       height: 32px;
       justify-content: flex-end;
       gap: 12px;
@@ -61,6 +67,7 @@
         white-space: nowrap;
         font-size: var(--font-size-base);
         font-weight: var(--font-weight-regular);
+        padding: 4px 8px 4px 4px;
       }
       [data-slot="select-select-trigger-icon"] {
         width: 16px;
@@ -91,17 +98,26 @@
 }
 
 [data-component="select-content"] {
-  min-width: 104px;
+  min-width: 8rem;
   max-width: 23rem;
   overflow: hidden;
   border-radius: var(--radius-md);
   background-color: var(--surface-raised-stronger-non-alpha);
   padding: 4px;
   box-shadow: var(--shadow-xs-border);
-  z-index: 60;
+  z-index: 50;
+  transform-origin: var(--kb-popper-content-transform-origin);
+  pointer-events: none;
+
+  animation: selectContentHide var(--transition-duration) var(--transition-easing) forwards;
+
+  @starting-style {
+    animation: none;
+  }
 
   &[data-expanded] {
-    animation: select-open 0.15s ease-out;
+    pointer-events: auto;
+    animation: selectContentShow var(--transition-duration) var(--transition-easing) forwards;
   }
 
   [data-slot="select-select-content-list"] {
@@ -111,43 +127,38 @@
     overflow-x: hidden;
     display: flex;
     flex-direction: column;
-
     &:focus {
       outline: none;
     }
-
     > *:not([role="presentation"]) + *:not([role="presentation"]) {
       margin-top: 2px;
     }
   }
-
   [data-slot="select-select-item"] {
     position: relative;
     display: flex;
     align-items: center;
-    padding: 2px 8px;
+    padding: 4px 8px;
     gap: 12px;
-    border-radius: 4px;
-    cursor: default;
+    border-radius: var(--radius-sm);
 
     /* text-12-medium */
     font-family: var(--font-family-sans);
-    font-size: var(--font-size-small);
+    font-size: var(--font-size-base);
     font-style: normal;
     font-weight: var(--font-weight-medium);
     line-height: var(--line-height-large); /* 166.667% */
     letter-spacing: var(--letter-spacing-normal);
-
     color: var(--text-strong);
 
-    transition:
-      background-color 0.2s ease-in-out,
-      color 0.2s ease-in-out;
+    transition-property: background-color, color;
+    transition-duration: var(--transition-duration);
+    transition-timing-function: var(--transition-easing);
     outline: none;
     user-select: none;
 
-    &[data-highlighted] {
-      background: var(--surface-raised-base-hover);
+    &:hover {
+      background-color: var(--surface-raised-base-hover);
     }
     &[data-disabled] {
       background-color: var(--surface-raised-base);
@@ -160,6 +171,11 @@
       margin-left: auto;
       width: 16px;
       height: 16px;
+      color: var(--icon-strong-base);
+
+      svg {
+        color: var(--icon-strong-base);
+      }
     }
     &:focus {
       outline: none;
@@ -171,13 +187,9 @@
 }
 
 [data-component="select-content"][data-trigger-style="settings"] {
-  min-width: 160px;
+  field-sizing: content;
   border-radius: 8px;
-  padding: 0;
-
-  [data-slot="select-select-content-list"] {
-    padding: 4px;
-  }
+  padding: 0 0 0 4px;
 
   [data-slot="select-select-item"] {
     /* text-14-regular */
@@ -190,13 +202,24 @@
   }
 }
 
-@keyframes select-open {
+@keyframes selectContentShow {
   from {
     opacity: 0;
-    transform: scale(0.95);
+    transform: scaleY(0.95);
   }
   to {
     opacity: 1;
-    transform: scale(1);
+    transform: scaleY(1);
+  }
+}
+
+@keyframes selectContentHide {
+  from {
+    opacity: 1;
+    transform: scaleY(1);
+  }
+  to {
+    opacity: 0;
+    transform: scaleY(0.95);
   }
 }
diff --git a/packages/ui/src/components/select.tsx b/packages/ui/src/components/select.tsx
index 0386c329ec4b..66f48e69b106 100644
--- a/packages/ui/src/components/select.tsx
+++ b/packages/ui/src/components/select.tsx
@@ -1,8 +1,10 @@
 import { Select as Kobalte } from "@kobalte/core/select"
-import { createMemo, onCleanup, splitProps, type ComponentProps, type JSX } from "solid-js"
+import { createMemo, createSignal, onCleanup, splitProps, type ComponentProps, type JSX } from "solid-js"
 import { pipe, groupBy, entries, map } from "remeda"
+import { Show } from "solid-js"
 import { Button, ButtonProps } from "./button"
 import { Icon } from "./icon"
+import { MorphChevron } from "./morph-chevron"
 
 export type SelectProps<T> = Omit<ComponentProps<typeof Kobalte<T>>, "value" | "onSelect" | "children"> & {
   placeholder?: string
@@ -38,6 +40,8 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
     "triggerVariant",
   ])
 
+  const [isOpen, setIsOpen] = createSignal(false)
+
   const state = {
     key: undefined as string | undefined,
     cleanup: undefined as (() => void) | void,
@@ -85,7 +89,7 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
       data-component="select"
       data-trigger-style={local.triggerVariant}
       placement={local.triggerVariant === "settings" ? "bottom-end" : "bottom-start"}
-      gutter={4}
+      gutter={8}
       value={local.current}
       options={grouped()}
       optionValue={(x) => (local.value ? local.value(x) : (x as string))}
@@ -115,7 +119,7 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
                 : (itemProps.item.rawValue as string)}
           </Kobalte.ItemLabel>
           <Kobalte.ItemIndicator data-slot="select-select-item-indicator">
-            <Icon name="check-small" size="small" />
+            <Icon name="check" size="small" />
           </Kobalte.ItemIndicator>
         </Kobalte.Item>
       )}
@@ -124,6 +128,7 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
         stop()
       }}
       onOpenChange={(open) => {
+        setIsOpen(open)
         local.onOpenChange?.(open)
         if (!open) stop()
       }}
@@ -149,7 +154,12 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
           }}
         </Kobalte.Value>
         <Kobalte.Icon data-slot="select-select-trigger-icon">
-          <Icon name={local.triggerVariant === "settings" ? "selector" : "chevron-down"} size="small" />
+          <Show when={local.triggerVariant === "settings"}>
+            <Icon name="selector" size="small" />
+          </Show>
+          <Show when={local.triggerVariant !== "settings"}>
+            <MorphChevron expanded={isOpen()} />
+          </Show>
         </Kobalte.Icon>
       </Kobalte.Trigger>
       <Kobalte.Portal>
@@ -166,4 +176,4 @@ export function Select<T>(props: SelectProps<T> & Omit<ButtonProps, "children">)
       </Kobalte.Portal>
     </Kobalte>
   )
-}
+}
\ No newline at end of file
diff --git a/packages/ui/src/styles/index.css b/packages/ui/src/styles/index.css
index 3ed0310ef2b6..cae48137ba60 100644
--- a/packages/ui/src/styles/index.css
+++ b/packages/ui/src/styles/index.css
@@ -48,6 +48,8 @@
 @import "../components/toast.css" layer(components);
 @import "../components/tooltip.css" layer(components);
 @import "../components/typewriter.css" layer(components);
+@import "../components/morph-chevron.css" layer(components);
+@import "../components/reasoning-icon.css" layer(components);
 
 @import "./utilities.css" layer(utilities);
 @import "./animations.css" layer(utilities);
diff --git a/packages/ui/src/styles/utilities.css b/packages/ui/src/styles/utilities.css
index 8c954f1fe4e7..82a913c8830c 100644
--- a/packages/ui/src/styles/utilities.css
+++ b/packages/ui/src/styles/utilities.css
@@ -1,6 +1,17 @@
 :root {
   interpolate-size: allow-keywords;
 
+  /* Transition tokens */
+  --transition-duration: 200ms;
+  --transition-easing: cubic-bezier(0.25, 0, 0.5, 1);
+  --transition-fast: 150ms;
+  --transition-slow: 300ms;
+
+  /* Allow height transitions from 0 to auto */
+  @supports (interpolate-size: allow-keywords) {
+    interpolate-size: allow-keywords;
+  }
+
   [data-popper-positioner] {
     pointer-events: none;
   }
@@ -129,3 +140,34 @@
   line-height: var(--line-height-x-large); /* 120% */
   letter-spacing: var(--letter-spacing-tightest);
 }
+
+/* Transition utility classes */
+.transition-colors {
+  transition-property: background-color, border-color, color, fill, stroke;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+}
+
+.transition-opacity {
+  transition-property: opacity;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+}
+
+.transition-transform {
+  transition-property: transform;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+}
+
+.transition-shadow {
+  transition-property: box-shadow;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+}
+
+.transition-interactive {
+  transition-property: background-color, border-color, color, box-shadow, opacity;
+  transition-duration: var(--transition-duration);
+  transition-timing-function: var(--transition-easing);
+}