diff --git a/backend/services/node_specs.py b/backend/services/node_specs.py
index fa7c359..3ad9da2 100644
--- a/backend/services/node_specs.py
+++ b/backend/services/node_specs.py
@@ -56,7 +56,7 @@ NODE_SPECS: list[dict[str, Any]] = [
         "description": "终止节点,礼貌结束对话。可有多个,均无出边。",
         "icon": "Flag",
         "accent": "rose",
-        "addable": False,
+        "addable": True,
         "constraints": {"minIncoming": 1, "minOutgoing": 0, "maxOutgoing": 0},
         "fields": [
             {"key": "name", "label": "节点名称", "type": "text"},
diff --git a/frontend/src/components/workflow/GenericNode.tsx b/frontend/src/components/workflow/GenericNode.tsx
index 9a562d1..f65e374 100644
--- a/frontend/src/components/workflow/GenericNode.tsx
+++ b/frontend/src/components/workflow/GenericNode.tsx
@@ -6,7 +6,7 @@
  */
 
 import { Handle, Position, type NodeProps } from "@xyflow/react";
-import { Pencil, Trash2 } from "lucide-react";
+import { MessageSquareText, Pencil, Trash2 } from "lucide-react";
 import { useContext } from "react";
 
 import { cn } from "@/lib/utils";
@@ -35,22 +35,30 @@ export function GenericNode({ id, type, data, selected }: NodeProps) {
     <div
       data-node-id={id}
       className={cn(
-        "group relative w-[228px] rounded-2xl border bg-card p-4 shadow-sm transition-all",
+        "group relative w-[250px] rounded-2xl border bg-card p-4 text-card-foreground shadow-sm transition-[border-color,box-shadow,transform]",
         isActive
-          ? "border-success ring-2 ring-success/60"
+          ? "border-success shadow-[0_12px_34px_color-mix(in_srgb,var(--success)_20%,transparent)] ring-2 ring-success/50"
           : selected
-            ? "border-primary ring-2 ring-primary/30"
-            : "border-hairline hover:shadow-md",
+            ? "border-primary shadow-[0_12px_34px_color-mix(in_srgb,var(--primary)_16%,transparent)]"
+            : "border-hairline hover:border-hairline-strong hover:shadow-md",
       )}
     >
       {spec.hasTarget && (
         <Handle
           type="target"
           position={Position.Left}
-          className="!h-2.5 !w-2.5 !border-2 !border-card !bg-muted-soft"
+          className="!h-3 !w-3 !border-[3px] !border-card !bg-muted-soft"
         />
       )}
 
+      <div
+        aria-hidden
+        className="absolute left-5 right-5 top-0 h-px"
+        style={{
+          background: `linear-gradient(90deg, transparent, var(${accentVar(spec.accent)}), transparent)`,
+        }}
+      />
+
       {isActive && (
         <div className="absolute -top-3 left-3 flex items-center gap-1.5 rounded-full bg-success px-2 py-0.5 text-[10px] font-medium text-on-primary shadow-sm">
           <span className="h-1.5 w-1.5 animate-pulse rounded-full bg-on-primary" />
@@ -78,7 +86,7 @@ export function GenericNode({ id, type, data, selected }: NodeProps) {
         >
           <Pencil size={13} />
         </button>
-        {spec.addable && (
+        {type !== "startCall" && (
           <button
             type="button"
             title="删除节点"
@@ -93,30 +101,31 @@ export function GenericNode({ id, type, data, selected }: NodeProps) {
         )}
       </div>
 
-      <div className="flex items-center gap-3">
+      <div className="flex items-start gap-3">
         <div
-          className="flex h-9 w-9 shrink-0 items-center justify-center rounded-xl text-ink"
+          className="flex h-10 w-10 shrink-0 items-center justify-center rounded-full text-foreground"
           style={{
-            backgroundImage: `radial-gradient(circle at 30% 30%, color-mix(in srgb, var(${accentVar(spec.accent)}) 70%, transparent), color-mix(in srgb, var(${accentVar(spec.accent)}) 35%, transparent))`,
+            background: `color-mix(in srgb, var(${accentVar(spec.accent)}) 28%, var(--surface-strong))`,
           }}
         >
-          <Icon size={18} />
+          <Icon size={17} />
         </div>
         <div className="min-w-0 flex-1">
-          <div className="truncate text-sm font-medium text-foreground">
+          <div className="caption-label text-muted-soft">{spec.displayName}</div>
+          <div className="mt-1 truncate text-sm font-medium text-foreground">
             {nodeData.name || spec.displayName}
           </div>
-          <div className="caption-label text-muted-soft">{spec.displayName}</div>
         </div>
+        <MessageSquareText size={15} className="mt-1 text-muted-soft" />
       </div>
 
       {preview ? (
-        <p className="mt-3 line-clamp-2 text-xs leading-5 text-muted-foreground">
+        <p className="mt-4 line-clamp-2 border-t border-hairline-soft pt-3 text-xs leading-5 text-muted-foreground">
           {preview}
         </p>
       ) : (
-        <p className="mt-3 text-xs italic leading-5 text-muted-soft">
-          点击编辑节点内容…
+        <p className="mt-4 border-t border-hairline-soft pt-3 text-xs leading-5 text-muted-foreground">
+          {spec.description}
         </p>
       )}
 
@@ -124,7 +133,7 @@ export function GenericNode({ id, type, data, selected }: NodeProps) {
         <Handle
           type="source"
           position={Position.Right}
-          className="!h-2.5 !w-2.5 !border-2 !border-card !bg-primary"
+          className="!h-3 !w-3 !border-[3px] !border-card !bg-primary"
         />
       )}
     </div>
diff --git a/frontend/src/components/workflow/WorkflowEditor.tsx b/frontend/src/components/workflow/WorkflowEditor.tsx
index cf183ab..78cf0c5 100644
--- a/frontend/src/components/workflow/WorkflowEditor.tsx
+++ b/frontend/src/components/workflow/WorkflowEditor.tsx
@@ -17,6 +17,7 @@ import {
   type Edge,
   MiniMap,
   type Node,
+  type NodeChange,
   Panel,
   ReactFlow,
   ReactFlowProvider,
@@ -214,11 +215,26 @@ function Canvas({
 
   const deleteNode = useCallback(
     (id: string) => {
+      if (nodes.find((node) => node.id === id)?.type === "startCall") return;
       setNodes((ns) => ns.filter((n) => n.id !== id));
       setEdges((es) => es.filter((e) => e.source !== id && e.target !== id));
       setEditingId((cur) => (cur === id ? null : cur));
     },
-    [setNodes, setEdges],
+    [nodes, setNodes, setEdges],
+  );
+
+  const handleNodesChange = useCallback(
+    (changes: NodeChange[]) => {
+      const startIds = new Set(
+        nodes.filter((node) => node.type === "startCall").map((node) => node.id),
+      );
+      onNodesChange(
+        changes.filter(
+          (change) => change.type !== "remove" || !startIds.has(change.id),
+        ),
+      );
+    },
+    [nodes, onNodesChange],
   );
 
   const updateEdgeData = useCallback(
@@ -259,96 +275,151 @@ function Canvas({
       <ActiveNodeContext.Provider value={activeNodeId ?? null}>
       <NodeActionContext.Provider value={nodeActions}>
         <EdgeActionContext.Provider value={edgeActions}>
-          <div className="h-full w-full overflow-hidden rounded-2xl border border-hairline bg-canvas-soft">
-            <ReactFlow
-              nodes={nodes}
-              edges={edges}
-              nodeTypes={nodeTypes}
-              edgeTypes={edgeTypes}
-              onNodesChange={onNodesChange}
-              onEdgesChange={onEdgesChange}
-              onConnect={onConnect}
-              isValidConnection={isValidConnection}
-              onPaneClick={() => {
-                setEditingId(null);
-                setEditingEdgeId(null);
-              }}
-              fitView
-              proOptions={{ hideAttribution: true }}
-              defaultEdgeOptions={{ type: "condition", animated: true }}
-              className="bg-canvas-soft"
-            >
-              <Background
-                variant={BackgroundVariant.Dots}
-                gap={20}
-                size={1}
-                color="var(--hairline-strong)"
+          <div className="h-full w-full min-h-[560px]">
+            <section className="relative h-full w-full overflow-hidden rounded-2xl border border-hairline bg-canvas-soft shadow-sm">
+              <div
+                aria-hidden
+                className="pointer-events-none absolute -right-24 -top-24 z-0 h-80 w-80 rounded-full opacity-30 blur-3xl"
+                style={{
+                  background:
+                    "radial-gradient(circle, var(--gradient-sky), transparent 68%)",
+                }}
               />
-              <Controls className="!rounded-xl !border !border-hairline !bg-card !shadow-sm [&_button]:!border-hairline [&_button]:!bg-card [&_button]:!text-foreground" />
-              <MiniMap
-                pannable
-                zoomable
-                className="!rounded-xl !border !border-hairline !bg-card"
-                maskColor="color-mix(in srgb, var(--canvas-soft) 70%, transparent)"
-                nodeColor="var(--surface-strong)"
+              <div
+                aria-hidden
+                className="pointer-events-none absolute -bottom-28 left-1/4 z-0 h-72 w-72 rounded-full opacity-25 blur-3xl"
+                style={{
+                  background:
+                    "radial-gradient(circle, var(--gradient-lavender), transparent 68%)",
+                }}
               />
-              <Panel position="top-left" className="flex gap-2">
-                <Button size="sm" className="gap-2" onClick={() => setAddOpen(true)}>
-                  <Plus size={15} />
-                  添加节点
-                </Button>
-                <Button
-                  size="sm"
-                  variant="outline"
-                  className="gap-2 border-hairline-strong bg-card text-foreground hover:bg-surface-strong"
-                  onClick={() => setSettingsOpen(true)}
-                >
-                  <Settings2 size={15} />
-                  工作流设置
-                </Button>
-              </Panel>
-            </ReactFlow>
+
+              <ReactFlow
+                nodes={nodes}
+                edges={edges}
+                nodeTypes={nodeTypes}
+                edgeTypes={edgeTypes}
+                onNodesChange={handleNodesChange}
+                onEdgesChange={onEdgesChange}
+                onConnect={onConnect}
+                isValidConnection={isValidConnection}
+                onPaneClick={() => {
+                  setEditingId(null);
+                  setEditingEdgeId(null);
+                }}
+                fitView
+                proOptions={{ hideAttribution: true }}
+                defaultEdgeOptions={{ type: "condition", animated: true }}
+              >
+                <Background
+                  variant={BackgroundVariant.Dots}
+                  gap={22}
+                  size={1}
+                  color="var(--hairline-strong)"
+                />
+                <Controls
+                  className="!rounded-xl !border !border-hairline !bg-card !shadow-sm [&_button]:!border-hairline [&_button]:!bg-card [&_button]:!text-foreground"
+                />
+                <MiniMap
+                  pannable
+                  zoomable
+                  className="!rounded-xl !border !border-hairline !bg-card"
+                  maskColor="color-mix(in srgb, var(--canvas-soft) 70%, transparent)"
+                  nodeColor="var(--surface-strong)"
+                />
+                <Panel position="top-left" className="flex gap-2">
+                  <Button
+                    size="sm"
+                    className="gap-2"
+                    onClick={() => setAddOpen(true)}
+                  >
+                    <Plus size={15} />
+                    添加节点
+                  </Button>
+                  <Button
+                    size="sm"
+                    variant="outline"
+                    className="gap-2 border-hairline-strong bg-card text-foreground hover:bg-surface-strong"
+                    onClick={() => setSettingsOpen(true)}
+                  >
+                    <Settings2 size={15} />
+                    工作流设置
+                  </Button>
+                </Panel>
+              </ReactFlow>
+            </section>
 
             {/* 添加节点弹窗 */}
             <Dialog open={addOpen} onOpenChange={setAddOpen}>
-              <DialogContent className="sm:max-w-[460px]">
-                <DialogHeader>
-                  <DialogTitle className="font-display text-ink">
-                    添加节点
-                  </DialogTitle>
-                  <DialogDescription>
-                    选择要添加到画布的节点类型。
-                  </DialogDescription>
+              <DialogContent className="gap-0 overflow-hidden border border-hairline bg-card p-0 shadow-2xl sm:max-w-[500px]">
+                <DialogHeader className="relative overflow-hidden border-b border-hairline px-6 py-6 pr-16">
+                  <div
+                    aria-hidden
+                    className="pointer-events-none absolute -right-14 -top-16 h-40 w-40 rounded-full opacity-40 blur-3xl"
+                    style={{
+                      background:
+                        "radial-gradient(circle, var(--gradient-sky), transparent 68%)",
+                    }}
+                  />
+                  <div className="relative flex items-start gap-4">
+                    <div className="flex h-11 w-11 shrink-0 items-center justify-center rounded-full bg-surface-strong text-foreground">
+                      <Plus size={18} />
+                    </div>
+                    <div>
+                      <div className="caption-label text-muted-soft">
+                        节点目录
+                      </div>
+                      <DialogTitle className="font-display display-sm mt-1 text-ink">
+                        添加节点
+                      </DialogTitle>
+                      <DialogDescription className="mt-2 leading-6">
+                        选择节点类型并添加到画布中央，随后可编辑内容并建立连线。
+                      </DialogDescription>
+                    </div>
+                  </div>
                 </DialogHeader>
-                <div className="flex flex-col gap-2 py-2">
-                  {addableSpecs.length === 0 && (
-                    <p className="text-sm text-muted-soft">暂无可添加的节点类型。</p>
-                  )}
+                <div className="flex max-h-[440px] flex-col gap-3 overflow-y-auto bg-canvas-soft/70 p-4">
+                  {addableSpecs.length === 0 ? (
+                    <p className="rounded-2xl border border-dashed border-hairline-strong bg-card px-4 py-8 text-center text-sm text-muted-soft">
+                      暂无可添加的节点类型。
+                    </p>
+                  ) : null}
                   {addableSpecs.map((spec) => {
                     const Icon = spec.icon;
                     return (
                       <button
                         key={spec.type}
                         type="button"
-                        className="flex items-start gap-3 rounded-xl border border-hairline bg-card p-3 text-left transition-colors hover:border-primary hover:bg-surface-strong/40"
+                        className="group relative flex items-start gap-4 overflow-hidden rounded-2xl border border-hairline bg-card p-4 text-left shadow-sm transition-[border-color,box-shadow,transform] hover:-translate-y-0.5 hover:border-hairline-strong hover:shadow-md"
                         onClick={() => addNode(spec)}
                       >
-                        <div
-                          className="flex h-9 w-9 shrink-0 items-center justify-center rounded-xl text-ink"
+                        <span
+                          aria-hidden
+                          className="absolute left-5 right-5 top-0 h-px"
                           style={{
-                            backgroundImage: `radial-gradient(circle at 30% 30%, color-mix(in srgb, var(${accentVar(spec.accent)}) 70%, transparent), color-mix(in srgb, var(${accentVar(spec.accent)}) 35%, transparent))`,
+                            background: `linear-gradient(90deg, transparent, var(${accentVar(spec.accent)}), transparent)`,
+                          }}
+                        />
+                        <div
+                          className="flex h-10 w-10 shrink-0 items-center justify-center rounded-full text-foreground transition-transform group-hover:scale-105"
+                          style={{
+                            background: `color-mix(in srgb, var(${accentVar(spec.accent)}) 28%, var(--surface-strong))`,
                           }}
                         >
-                          <Icon size={18} />
+                          <Icon size={17} />
                         </div>
-                        <div className="min-w-0">
+                        <div className="min-w-0 flex-1">
                           <div className="text-sm font-medium text-foreground">
                             {spec.displayName}
                           </div>
-                          <div className="mt-0.5 text-xs leading-5 text-muted-foreground">
+                          <div className="mt-1 text-xs leading-5 text-muted-foreground">
                             {spec.description}
                           </div>
                         </div>
+                        <Plus
+                          size={15}
+                          className="mt-1 shrink-0 text-muted-soft transition-colors group-hover:text-foreground"
+                        />
                       </button>
                     );
                   })}
@@ -358,16 +429,34 @@ function Canvas({
 
             {/* 工作流设置弹窗 */}
             <Dialog open={settingsOpen} onOpenChange={setSettingsOpen}>
-              <DialogContent className="sm:max-w-[460px]">
-                <DialogHeader>
-                  <DialogTitle className="font-display text-ink">
-                    工作流设置
-                  </DialogTitle>
-                  <DialogDescription>
-                    配置整个工作流使用的语音与大模型,以及交互策略。
-                  </DialogDescription>
+              <DialogContent className="gap-0 overflow-hidden border border-hairline bg-card p-0 shadow-2xl sm:max-w-[500px]">
+                <DialogHeader className="relative overflow-hidden border-b border-hairline px-6 py-6 pr-16">
+                  <div
+                    aria-hidden
+                    className="pointer-events-none absolute -right-14 -top-16 h-40 w-40 rounded-full opacity-40 blur-3xl"
+                    style={{
+                      background:
+                        "radial-gradient(circle, var(--gradient-lavender), transparent 68%)",
+                    }}
+                  />
+                  <div className="relative flex items-start gap-4">
+                    <div className="flex h-11 w-11 shrink-0 items-center justify-center rounded-full bg-surface-strong text-foreground">
+                      <Settings2 size={18} />
+                    </div>
+                    <div>
+                      <div className="caption-label text-muted-soft">
+                        全局配置
+                      </div>
+                      <DialogTitle className="font-display display-sm mt-1 text-ink">
+                        工作流设置
+                      </DialogTitle>
+                      <DialogDescription className="mt-2 leading-6">
+                        配置整个工作流使用的语音、大模型与交互策略。
+                      </DialogDescription>
+                    </div>
+                  </div>
                 </DialogHeader>
-                <div className="flex flex-col gap-5 py-2">
+                <div className="flex max-h-[62vh] flex-col gap-3 overflow-y-auto bg-canvas-soft/70 p-4">
                   <ModelSelect
                     label="大模型(LLM)"
                     value={settings.llm}
@@ -386,9 +475,14 @@ function Canvas({
                     options={modelOptions.tts}
                     onChange={(v) => onSettingsChange({ ...settings, tts: v })}
                   />
-                  <label className="flex items-center justify-between gap-3 pt-1">
-                    <span className="text-sm font-medium text-foreground">
-                      允许用户打断
+                  <label className="flex items-center justify-between gap-4 rounded-2xl border border-hairline bg-card p-4 shadow-sm">
+                    <span>
+                      <span className="block text-sm font-medium text-foreground">
+                        允许用户打断
+                      </span>
+                      <span className="mt-1 block text-xs leading-5 text-muted-foreground">
+                        用户说话时可中断当前语音回复。
+                      </span>
                     </span>
                     <Switch
                       checked={settings.allowInterrupt}
@@ -398,7 +492,7 @@ function Canvas({
                     />
                   </label>
                 </div>
-                <DialogFooter>
+                <DialogFooter className="border-t border-hairline bg-card px-5 py-4">
                   <Button onClick={() => setSettingsOpen(false)}>完成</Button>
                 </DialogFooter>
               </DialogContent>
@@ -420,7 +514,7 @@ function Canvas({
                       setEditingId(null);
                     }}
                     onDelete={
-                      editingSpec.addable
+                      editingNode.type !== "startCall"
                         ? () => deleteNode(editingNode.id)
                         : undefined
                     }
@@ -468,13 +562,13 @@ function ModelSelect({
   onChange: (value: string | undefined) => void;
 }) {
   return (
-    <div className="flex flex-col gap-2">
+    <div className="flex flex-col gap-2 rounded-2xl border border-hairline bg-card p-4 shadow-sm">
       <label className="text-sm font-medium text-foreground">{label}</label>
       <Select
         value={value ?? NONE}
         onValueChange={(v) => onChange(v === NONE ? undefined : v)}
       >
-        <SelectTrigger className="border-hairline-strong bg-background text-foreground">
+        <SelectTrigger className="w-full border-hairline-strong bg-canvas-soft text-foreground">
           <SelectValue placeholder="选择模型资源" />
         </SelectTrigger>
         <SelectContent>