diff --git a/src/pages/task/TaskDetail.jsx b/src/pages/task/TaskDetail.jsx
index 208a2ce..8264029 100644
--- a/src/pages/task/TaskDetail.jsx
+++ b/src/pages/task/TaskDetail.jsx
@@ -128,13 +128,15 @@ export default function TaskDetail({ task, projectCode, columns, members, tasks,
    *  这里始终按 String() 比对, 不要 Number(): 否则结果变 NaN, 落库列被改成 "NaN" 报「看板列不存在」 */
   function pickColumn() {
     const current = String(task.columnId)
-    ActionSheet.show({
+    const handler = ActionSheet.show({
       actions: (columns || []).map((c) => ({
         text: c.name + (String(c.id) === current ? ' ✓' : ''),
         key: String(c.id),
       })),
       cancelText: '取消',
       onAction: async (item) => {
+        // 选中即收起 sheet (与项目视图 ⋯ 菜单同口径); 否则改完列 sheet 还挂在那
+        handler.close?.()
         const columnId = String(item.key)
         if (columnId === current) return
         try {
@@ -200,28 +202,35 @@ export default function TaskDetail({ task, projectCode, columns, members, tasks,
         borderTopLeftRadius: 12,
         borderTopRightRadius: 12,
         maxHeight: `calc(88vh - ${kb}px)`,
-        overflowY: 'auto',
-        padding: `16px 16px calc(env(safe-area-inset-bottom, 0px) + 20px + ${kb}px)`,
+        // 三段式: 固定头 / 滚动体 / 固定底 (标题与保存按钮始终可见)
+        display: 'flex',
+        flexDirection: 'column',
+        overflow: 'hidden',
+        padding: 0,
       }}
     >
-      <div className="sheet-title">{task.title}</div>
-      {fullId && (
-        <div className="sheet-idrow">
-          <span
-            className="task-id-chip"
-            role="button"
-            title="点击复制完整任务编号"
-            onClick={copyId}
-          >
-            <span className="tid">{fullId}</span>
-            <span className="tid-copy">{copied ? '已复制' : '复制'}</span>
-          </span>
+      {/* 固定头部: 标题 + 看板列/状态 + 编号 */}
+      <div className="td-head">
+        <div className="sheet-title">{task.title}</div>
+        {/* 看板列 · 状态 与完整任务编号同一行, 编号靠右 (点按复制) */}
+        <div className="sheet-sub">
+          <span className="sub-meta">{currentCol?.name} · {STATUS_LABEL[task.status]}</span>
+          {fullId && (
+            <span
+              className="task-id-chip"
+              role="button"
+              title="点击复制完整任务编号"
+              onClick={copyId}
+            >
+              <span className="tid">{fullId}</span>
+              <span className="tid-copy">{copied ? '已复制' : '复制'}</span>
+            </span>
+          )}
         </div>
-      )}
-      <div className="sheet-sub">
-        {currentCol?.name} · {STATUS_LABEL[task.status]}
       </div>
 
+      {/* 可滚动主体: 只有这一段滚动 */}
+      <div className="td-body">
       <div className="field">
         <label>标题</label>
         <input
@@ -386,8 +395,15 @@ export default function TaskDetail({ task, projectCode, columns, members, tasks,
           }}
         />
       </div>
+      </div>{/* /.td-body */}
 
-      <div className="btn-primary" onClick={save}>{saving ? '保存中…' : '保存'}</div>
+      {/* 固定底部: 保存 (键盘弹出时随 kb 上抬) */}
+      <div
+        className="td-foot"
+        style={{ paddingBottom: `calc(env(safe-area-inset-bottom, 0px) + 12px + ${kb}px)` }}
+      >
+        <div className="btn-primary" onClick={save}>{saving ? '保存中…' : '保存'}</div>
+      </div>
 
       <UserPicker
         visible={picker === 'assignee'}
diff --git a/src/styles/globals.css b/src/styles/globals.css
index 0c03a0c..a7675d3 100644
--- a/src/styles/globals.css
+++ b/src/styles/globals.css
@@ -1135,18 +1135,37 @@ body.me-safe-top .app-safe-top { height: 0; }
 .cs-count { font-size: 11px; color: #999; margin-left: 8px; }
 
 /* ---- 任务详情 ---- */
+/* 三段式弹层: 固定头 / 滚动体 / 固定底 —— 标题与保存按钮始终可见 */
+.td-head {
+  flex: 0 0 auto; padding: 16px 16px 8px; background: #fff;
+  border-bottom: 1px solid var(--color-border);
+}
+.td-body {
+  flex: 1 1 auto; min-height: 0; overflow-y: auto;
+  padding: 12px 16px 4px;
+  -webkit-overflow-scrolling: touch; overscroll-behavior: contain;
+}
+.td-foot {
+  flex: 0 0 auto; padding: 10px 16px 12px; background: #fff;
+  border-top: 1px solid var(--color-border);
+}
+/* 底部固定后不再需要上外边距 */
+.td-foot .btn-primary { margin-top: 0; }
 .sheet-title {
   font-size: 16px; font-weight: 700; margin-bottom: 4px; word-break: break-word;
   display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
 }
+/* 详情页副标题行: 左侧「看板列 · 状态」, 右侧完整任务编号 (点按复制) */
 .sheet-sub {
+  display: flex; align-items: center; gap: 8px;
   font-size: 11.5px; color: #999; margin-bottom: 14px;
+}
+.sheet-sub .sub-meta {
+  flex: 1 1 auto; min-width: 0;
   overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
 }
-/* 详情页标题下的完整任务编号 (项目编号-序号): 点按复制 */
-.sheet-idrow { margin: -1px 0 6px; }
 .task-id-chip {
-  display: inline-flex; align-items: center; gap: 6px;
+  display: inline-flex; align-items: center; gap: 6px; flex-shrink: 0;
   font-size: 11px; line-height: 1; font-weight: 600;
   color: #5b6b7c; background: #eef2f6; border-radius: 999px; padding: 5px 9px;
   cursor: pointer; -webkit-user-select: none; user-select: none;