diff --git a/README.md b/README.md
index c0f5c25..2d79b11 100644
--- a/README.md
+++ b/README.md
@@ -109,8 +109,8 @@ const data = ref<WaveformData>({
 | `pannable`                        | `boolean`                                   | `false`                                                 | 空格拖拽平移开关                   |
 | `minZoomSpan`                     | `number`                                    | 未设置                                                  | 最小缩放跨度，使用原始 X 数据单位  |
 | `minVisiblePoints`                | `number`                                    | `0`                                                     | 缩放后至少保留的不同 X 坐标数      |
-| `initialXDomain`                  | `[number, number]`                          | 未设置                                                  | 所有图框的初始 X 范围              |
-| `initialXDomains`                 | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置初始范围    |
+| `initialXDomain`                  | `[number, number]`                          | 未设置                                                  | 所有图框的初始 X 范围（可超出数据，空白显示） |
+| `initialXDomains`                 | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置初始范围（可超出数据） |
 | `xDomainStrategy`                 | `WaveformXDomainStrategy`                   | `{ type: 'data' }`                                      | 自动 X 轴视口范围策略              |
 | `yDomain`                         | `[number, number]`                          | 未设置                                                  | 所有波形的固定 Y 轴范围            |
 | `yDomains`                        | `Record<string, [number, number]>`          | 未设置                                                  | 按 track/series ID 配置固定范围    |
@@ -247,7 +247,7 @@ X 轴且包含多个轨道时使用按稳定 track ID 索引的 `yRanges`。平
 调用方应处理加载失败的情况（网络错误、超时等），并保持旧数据或显示加载状态。生产环境建议使用
 `AbortController` 取消过时的请求。
 
-`initialXDomain` 固定首次完整数据的 X 轴缩放边界，不要将它改成后端返回的当前窗口；独立图框有不同时间范围时，可通过
+`initialXDomain` 固定首次及重置时的 X 轴视口范围，不要将它改成后端返回的当前窗口；范围可以超出数据的实际时间，超出部分保留空白。独立图框有不同时间范围时，可通过
 `initialXDomains` 按 track ID 或 series ID 分别配置。`minZoomSpan` 使用原始 X 数据单位，
 可防止每次区间数据回填后重新累计放大。双击图框会
 重置组件内部缩放并触发 `zoom-reset`；调用方应在事件中取消区间请求并恢复首次完整数据。
diff --git a/package.json b/package.json
index ab26692..f12e3cd 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "waveform-analysis",
-  "version": "0.1.36",
+  "version": "0.1.37",
   "main": "./dist/index.cjs",
   "module": "./dist/index.js",
   "types": "./dist/types/index.d.ts",
diff --git a/src/App.test.ts b/src/App.test.ts
index 0b45151..bcf783d 100644
--- a/src/App.test.ts
+++ b/src/App.test.ts
@@ -321,8 +321,9 @@ describe('App workspace layout', { timeout: 20_000 }, () => {
     const styleSelect = frameControls.findAllComponents(Select)[0]
 
     expect(colorPickers).toHaveLength(2)
-    expect(widthInput).toBeDefined()
-    expect(styleSelect).toBeDefined()
+
+    const initialFrames = wrapper.findAll('.waveform-chart__plot-frame')
+    expect(initialFrames.length > 1 && initialFrames.every((frame) => frame.attributes('stroke-width') === '2')).toBe(true)
 
     colorPickers[0].vm.$emit('update:pureColor', 'rgba(220, 38, 38, 0.8)')
     colorPickers[1].vm.$emit('update:pureColor', 'rgba(14, 165, 233, 0.25)')
diff --git a/src/App.vue b/src/App.vue
index 6c7ae6c..3dfee86 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -32,7 +32,7 @@ const overlayMode = ref<WaveformOverlayMode>('single-axis')
 const rowCount = ref(4)
 const columnCount = ref(1)
 const frameBorderColor = ref('#1f2937')
-const frameBorderWidth = ref(1)
+const frameBorderWidth = ref(2)
 const frameBorderStyle = ref<NonNullable<WaveformFrameStyle['borderStyle']>>('solid')
 const frameBackgroundColor = ref('rgba(255, 255, 255, 0)')
 const frameWatermarkVisible = ref(true)
diff --git a/src/components/WaveformChartView.vue b/src/components/WaveformChartView.vue
index 0008247..749b900 100644
--- a/src/components/WaveformChartView.vue
+++ b/src/components/WaveformChartView.vue
@@ -87,9 +87,11 @@ const {
   contextMenu,
   editorSeries,
   editorSeriesOptions,
+  timeError,
   confirmAnnotation,
   cancelAnnotation,
   changeDraftSeries,
+  changeDraftTime,
   editContextAnnotation,
   deleteContextAnnotation,
   chartHeight,
@@ -98,6 +100,11 @@ const {
   setTitleMeasureElement,
   setSharedOverlayElement,
 } = toRefs(props.controller)
+
+function handleChartPointerLeave() {
+  pointerInsideChart.value = false
+  handlePointerLeave.value()
+}
 </script>
 
 <template>
@@ -123,7 +130,7 @@ const {
     :data-plot-margin-bottom="resolvedPlotMargin.bottom"
     :data-title-area-height="titleAreaHeight"
     @pointerenter="pointerInsideChart = true"
-    @pointerleave="pointerInsideChart = false"
+    @pointerleave="handleChartPointerLeave"
     @contextmenu.capture="handleNativeContextMenu"
   >
     <div
@@ -332,9 +339,11 @@ const {
       :series="editorSeries"
       :series-options="editorSeriesOptions"
       :time-unit="timeUnit"
+      :time-error="timeError"
       @confirm="confirmAnnotation"
       @cancel="cancelAnnotation"
       @series-change="changeDraftSeries"
+      @time-change="changeDraftTime"
     />
 
     <WaveformAnnotationContextMenu
diff --git a/src/components/annotation/WaveformAnnotationEditor.css b/src/components/annotation/WaveformAnnotationEditor.css
index f8d5766..0b277e6 100644
--- a/src/components/annotation/WaveformAnnotationEditor.css
+++ b/src/components/annotation/WaveformAnnotationEditor.css
@@ -1,63 +1,8 @@
-.waveform-annotation-editor {
-  position: absolute;
-  inset: 0;
-  z-index: 40;
-  display: grid;
-  place-items: center;
-  padding: 20px;
-  background: rgb(16 24 40 / 32%);
-  animation: waveform-annotation-editor-fade-in 160ms ease-out;
-}
-.waveform-annotation-editor__panel {
+.waveform-annotation-editor__content {
   display: grid;
   gap: 20px;
-  width: min(440px, 100%);
-  max-height: 100%;
-  overflow-y: auto;
-  padding: 22px;
   color: #344054;
   font-size: 13px;
-  background: #fff;
-  border: 1px solid #e4e7ec;
-  border-radius: 12px;
-  box-shadow: 0 20px 50px rgb(16 24 40 / 22%);
-  animation: waveform-annotation-editor-rise-in 180ms ease-out;
-}
-.waveform-annotation-editor__header {
-  display: flex;
-  align-items: flex-start;
-  justify-content: space-between;
-  gap: 16px;
-}
-.waveform-annotation-editor__header h2 {
-  margin: 0;
-  color: #101828;
-  font-size: 18px;
-  line-height: 1.3;
-}
-.waveform-annotation-editor__header p {
-  margin: 5px 0 0;
-  color: #667085;
-  font-size: 12px;
-}
-.waveform-annotation-editor__close {
-  display: inline-grid;
-  flex: 0 0 30px;
-  width: 30px;
-  height: 30px;
-  padding: 0;
-  place-items: center;
-  color: #667085;
-  font-size: 22px;
-  line-height: 1;
-  background: transparent;
-  border: 0;
-  border-radius: 6px;
-  cursor: pointer;
-}
-.waveform-annotation-editor__close:hover {
-  color: #101828;
-  background: #f2f4f7;
 }
 .waveform-annotation-editor__coordinates {
   display: grid;
@@ -78,6 +23,39 @@
 .waveform-annotation-editor__coordinates span {
   color: #667085;
 }
+.waveform-annotation-editor__coordinate-input {
+  display: flex;
+  min-width: 0;
+  align-items: center;
+  gap: 8px;
+  padding: 9px 10px;
+  color: #667085;
+  background: #f8fafc;
+  border: 1px solid #eaecf0;
+  border-radius: 7px;
+}
+.waveform-annotation-editor__coordinate-input :deep(.ant-input-number) {
+  width: auto;
+  min-width: 96px;
+  color: #344054;
+  font-family: 'SFMono-Regular', Consolas, monospace;
+}
+.waveform-annotation-editor__coordinate-value {
+  display: none;
+}
+.waveform-annotation-editor__coordinate-error {
+  grid-column: 1 / -1;
+  margin: -12px 0 0;
+  color: #d92d20;
+  font-size: 11px;
+  line-height: 1.4;
+}
+.waveform-annotation-editor__coordinate-hint {
+  margin: -12px 0 0;
+  color: #98a2b3;
+  font-size: 11px;
+  line-height: 1.4;
+}
 .waveform-annotation-editor__coordinates b {
   color: #1677ff;
   font-size: 11px;
@@ -205,56 +183,9 @@
   border-color: #98a2b3;
   box-shadow: 0 0 0 3px rgb(22 119 255 / 12%);
 }
-.waveform-annotation-editor__actions {
-  display: flex;
-  justify-content: flex-end;
-  gap: 8px;
-  padding-top: 8px;
-  border-top: 1px solid #eaecf0;
-}
-.waveform-annotation-editor__actions button {
-  height: 34px;
-  padding: 0 12px;
-  color: #475467;
-  background: #fff;
-  border: 1px solid #d0d5dd;
-  border-radius: 6px;
-  cursor: pointer;
-}
-.waveform-annotation-editor__actions button.is-primary {
-  color: #fff;
-  background: #1677ff;
-  border-color: #1677ff;
-}
-.waveform-annotation-editor__actions button:disabled {
-  opacity: 0.45;
-  cursor: not-allowed;
-}
-@keyframes waveform-annotation-editor-fade-in {
-  from {
-    opacity: 0;
-  }
-  to {
-    opacity: 1;
-  }
-}
-@keyframes waveform-annotation-editor-rise-in {
-  from {
-    opacity: 0;
-    transform: translateY(8px) scale(0.98);
-  }
-  to {
-    opacity: 1;
-    transform: translateY(0) scale(1);
-  }
-}
 @media (max-width: 420px) {
-  .waveform-annotation-editor {
-    padding: 12px;
-  }
-  .waveform-annotation-editor__panel {
+  .waveform-annotation-editor__content {
     gap: 16px;
-    padding: 18px;
   }
   .waveform-annotation-editor__coordinates {
     grid-template-columns: 1fr;
diff --git a/src/components/annotation/WaveformAnnotationEditor.vue b/src/components/annotation/WaveformAnnotationEditor.vue
index a4faee0..b8d830f 100644
--- a/src/components/annotation/WaveformAnnotationEditor.vue
+++ b/src/components/annotation/WaveformAnnotationEditor.vue
@@ -1,5 +1,6 @@
 <script setup lang="ts">
 import { computed, nextTick, ref, watch } from 'vue'
+import { InputNumber, Modal } from 'ant-design-vue'
 import { ColorPicker } from 'vue3-colorpicker'
 import 'vue3-colorpicker/style.css'
 
@@ -15,24 +16,44 @@ interface Props {
   series?: AnnotationSeriesInfo
   seriesOptions?: AnnotationSeriesCandidate[]
   timeUnit?: TimeUnit
+  timeError?: string
 }
 
 const props = withDefaults(defineProps<Props>(), {
   timeUnit: 'ms',
+  timeError: '',
 })
 const emit = defineEmits<{
   (event: 'confirm', annotation: WaveformAnnotation): void
   (event: 'cancel'): void
   (event: 'series-change', seriesId: string): void
+  (event: 'time-change', displayValue: string): void
 }>()
 
 const textarea = ref<HTMLTextAreaElement>()
 const dialogTitleId = useWaveformInstanceId('waveform-annotation-editor-title')
 const text = ref('')
+const timeInput = ref('')
+const timeValidationRequested = ref(false)
 const borderColor = ref('')
 const textColor = ref('')
 const backgroundColor = ref('')
-const canConfirm = computed(() => text.value.trim().length > 0)
+const inputTimeError = computed(() => {
+  if (!timeValidationRequested.value) return ''
+  if (!timeInput.value.trim() || !Number.isFinite(Number(timeInput.value)))
+    return '请输入有效的时间'
+  return ''
+})
+const timeErrorMessage = computed(() =>
+  timeValidationRequested.value ? inputTimeError.value || props.timeError || '' : '',
+)
+const canConfirm = computed(
+  () =>
+    text.value.trim().length > 0 &&
+    timeInput.value.trim().length > 0 &&
+    Number.isFinite(Number(timeInput.value)) &&
+    !timeErrorMessage.value,
+)
 const characterCount = computed(() => text.value.length)
 const selectedSeries = computed(() => {
   const option = props.seriesOptions?.find(
@@ -46,15 +67,30 @@ const selectedSeries = computed(() => {
 function hydrate() {
   const style = resolveAnnotationStyle(props.annotation.style)
   text.value = props.annotation.text
+  timeInput.value = formatAnnotationTime(props.annotation.x, props.timeUnit)
+  timeValidationRequested.value = false
   borderColor.value = style.borderColor
   textColor.value = style.textColor
   backgroundColor.value = style.backgroundColor
   void nextTick(() => textarea.value?.focus())
 }
 
-watch(() => props.annotation, hydrate, { immediate: true })
+watch(() => props.annotation.id, hydrate, { immediate: true })
 
-function confirm() {
+function handleTimeInput(value: number | string | null) {
+  const nextValue = value === null || value === undefined ? '' : String(value)
+  timeInput.value = nextValue
+  timeValidationRequested.value = false
+}
+
+function commitTimeInput() {
+  timeValidationRequested.value = true
+  emit('time-change', timeInput.value)
+}
+
+async function confirm() {
+  commitTimeInput()
+  await nextTick()
   if (!canConfirm.value) return
   emit('confirm', {
     ...props.annotation,
@@ -82,40 +118,60 @@ function handleSeriesChange(event: Event) {
 </script>
 
 <template>
-  <div
-    class="waveform-annotation-editor"
-    role="dialog"
-    aria-modal="true"
-    :aria-labelledby="dialogTitleId"
-    @click.self="emit('cancel')"
+  <Modal
+    :visible="true"
+    :width="440"
+    :mask-closable="true"
+    :keyboard="true"
+    cancel-text="取消"
+    ok-text="保存标注"
+    :ok-button-props="{ disabled: !canConfirm }"
+    wrap-class-name="waveform-annotation-editor"
+    @cancel="emit('cancel')"
+    @ok="confirm"
   >
-    <section class="waveform-annotation-editor__panel">
-      <header class="waveform-annotation-editor__header">
-        <div>
-          <h2 :id="dialogTitleId">
-            {{ props.mode === 'add' ? '添加标注' : '编辑标注' }}
-          </h2>
-        </div>
-        <button
-          type="button"
-          class="waveform-annotation-editor__close"
-          aria-label="关闭标注编辑器"
-          title="关闭"
-          @click="emit('cancel')"
-        >
-          ×
-        </button>
-      </header>
+    <template #title>
+      <span :id="dialogTitleId">{{ props.mode === 'add' ? '添加标注' : '编辑标注' }}</span>
+    </template>
 
+    <div class="waveform-annotation-editor__content">
       <div class="waveform-annotation-editor__coordinates" aria-label="标注坐标">
-        <span
-          ><b>X ({{ props.timeUnit }})</b
-          ><code>{{ formatAnnotationTime(props.annotation.x, props.timeUnit) }}</code></span
+        <label
+          class="waveform-annotation-editor__coordinate-input"
+          :aria-invalid="Boolean(timeErrorMessage)"
         >
+          <b>X</b>
+          <InputNumber
+            :value="timeInput === '' ? undefined : Number(timeInput)"
+            :controls="true"
+            :step="0.001"
+            :keyboard="true"
+            :status="timeErrorMessage ? 'error' : undefined"
+            aria-label="标注横轴时间"
+            :aria-invalid="Boolean(timeErrorMessage)"
+            :aria-describedby="timeErrorMessage ? `${dialogTitleId}-time-error` : undefined"
+            @blur="commitTimeInput"
+            @update:value="handleTimeInput"
+          />
+          <code class="waveform-annotation-editor__coordinate-value" aria-hidden="true">{{
+            timeInput
+          }}</code>
+        </label>
+        <p
+          v-if="timeErrorMessage"
+          :id="`${dialogTitleId}-time-error`"
+          class="waveform-annotation-editor__coordinate-error"
+          role="alert"
+        >
+          {{ timeErrorMessage }}
+        </p>
         <span
           ><b>Y</b><code>{{ formatPlainNumber(props.annotation.y) }}</code></span
         >
       </div>
+      <p class="waveform-annotation-editor__coordinate-hint" role="note">
+        修改 X 轴后失焦时会自动吸附最近的采样点
+      </p>
 
       <label
         v-if="selectedSeries"
@@ -200,14 +256,8 @@ function handleSeriesChange(event: Event) {
         </label>
       </fieldset>
 
-      <footer class="waveform-annotation-editor__actions">
-        <button type="button" @click="emit('cancel')">取消</button>
-        <button type="button" class="is-primary" :disabled="!canConfirm" @click="confirm">
-          保存标注
-        </button>
-      </footer>
-    </section>
-  </div>
+    </div>
+  </Modal>
 </template>
 
 <style scoped src="./WaveformAnnotationEditor.css"></style>
diff --git a/src/components/annotation/components.test.ts b/src/components/annotation/components.test.ts
index 3a1d8ee..9190b79 100644
--- a/src/components/annotation/components.test.ts
+++ b/src/components/annotation/components.test.ts
@@ -1,28 +1,93 @@
 import { flushPromises, mount } from '@vue/test-utils'
-import { describe, expect, it, vi } from 'vitest'
+import { InputNumber } from 'ant-design-vue'
+import { afterEach, describe, expect, it, vi } from 'vitest'
 import { ColorPicker } from 'vue3-colorpicker'
+import { defineComponent, h } from 'vue'
 
 import WaveformAnnotationContextMenu from './WaveformAnnotationContextMenu.vue'
 import WaveformAnnotationEditor from './WaveformAnnotationEditor.vue'
 import WaveformAnnotationLayer from './WaveformAnnotationLayer.vue'
 
+const modalStub = defineComponent({
+  props: [
+    'visible',
+    'width',
+    'maskClosable',
+    'keyboard',
+    'wrapClassName',
+    'cancelText',
+    'okText',
+    'okButtonProps',
+  ],
+  emits: ['cancel', 'ok'],
+  setup(props, { emit, slots }) {
+    return () => {
+      const title = slots.title?.() ?? []
+      const titleId = (title[0]?.props as { id?: string } | undefined)?.id
+      return h('div', { class: 'ant-modal-root' }, [
+        h(
+          'div',
+          {
+            class: ['ant-modal-wrap', props.wrapClassName],
+            role: 'dialog',
+            'aria-modal': 'true',
+            'aria-labelledby': titleId,
+            onClick: (event: MouseEvent) => {
+              if (event.target === event.currentTarget && props.maskClosable) emit('cancel')
+            },
+          },
+          [
+            h('div', { class: 'ant-modal' }, [
+              h('div', { class: 'ant-modal-header' }, [
+                h('div', { class: 'ant-modal-title' }, title),
+              ]),
+              h('button', { class: 'ant-modal-close', onClick: () => emit('cancel') }, '×'),
+              slots.default?.(),
+              h('div', { class: 'ant-modal-footer' }, [
+                h('button', { class: 'ant-btn', onClick: () => emit('cancel') }, props.cancelText),
+                h(
+                  'button',
+                  {
+                    class: 'ant-btn ant-btn-primary',
+                    disabled: props.okButtonProps?.disabled,
+                    onClick: () => emit('ok'),
+                  },
+                  props.okText,
+                ),
+              ]),
+            ]),
+          ],
+        ),
+      ])
+    }
+  },
+})
+const mountEditor = (options: { props: Record<string, unknown> }) =>
+  mount(WaveformAnnotationEditor, {
+    props: options.props as never,
+    global: { stubs: { Modal: modalStub, AModal: modalStub } },
+  })
+
 describe('waveform annotation controls', () => {
+  afterEach(() => {
+    document.body.innerHTML = ''
+  })
   it('keeps dialog title ids unique across editor instances', () => {
-    const first = mount(WaveformAnnotationEditor, {
+    const first = mountEditor({
       props: {
         annotation: { id: 'first', seriesId: 'a', x: 1, y: 2, text: '说明' },
         mode: 'edit',
       },
     })
-    const second = mount(WaveformAnnotationEditor, {
+    const second = mountEditor({
       props: {
         annotation: { id: 'second', seriesId: 'a', x: 1, y: 2, text: '说明' },
         mode: 'edit',
       },
     })
 
-    const firstTitleId = first.get('h2').attributes('id')
-    const secondTitleId = second.get('h2').attributes('id')
+    const firstTitleId = first.get('.ant-modal-title [id]').attributes('id')
+    const secondTitleId = second.get('.ant-modal-title [id]').attributes('id')
 
     expect(firstTitleId).toBeTruthy()
     expect(secondTitleId).toBeTruthy()
@@ -31,8 +96,19 @@ describe('waveform annotation controls', () => {
     expect(second.get('[role="dialog"]').attributes('aria-labelledby')).toBe(secondTitleId)
   })
 
+  it.each(['add', 'edit'] as const)('shows the X-axis snapping hint in %s mode', (mode) => {
+    const wrapper = mountEditor({
+      props: {
+        annotation: { id: `hint-${mode}`, seriesId: 'a', x: 1, y: 2, text: '说明' },
+        mode,
+      },
+    })
+
+    expect(wrapper.get('[role="note"]').text()).toBe('修改 X 轴后失焦时会自动吸附最近的采样点')
+  })
+
   it('allows changing the annotation series inside the editor', async () => {
-    const wrapper = mount(WaveformAnnotationEditor, {
+    const wrapper = mountEditor({
       props: {
         annotation: { id: 'note', seriesId: 'a', x: 1, y: 2, text: '说明' },
         mode: 'edit',
@@ -77,17 +153,15 @@ describe('waveform annotation controls', () => {
 
   it('validates text and emits an immutable edited annotation with style defaults', async () => {
     const annotation = { id: 'note', seriesId: 'a', x: 1, y: 2, text: '' }
-    const wrapper = mount(WaveformAnnotationEditor, {
+    const wrapper = mountEditor({
       props: { annotation, mode: 'add' },
     })
     await flushPromises()
 
     expect(wrapper.get('textarea').attributes('maxlength')).toBe('40')
-    expect(wrapper.get('.waveform-annotation-editor__coordinates').text()).toContain(
-      'X (ms)1000.000',
-    )
+    expect(wrapper.get('.waveform-annotation-editor__coordinates').text()).toContain('X1000.000')
     expect(wrapper.get('.waveform-annotation-editor__coordinates').text()).toContain('Y2')
-    expect(wrapper.get('button.is-primary').attributes('disabled')).toBeDefined()
+    expect(wrapper.get('button.ant-btn-primary').attributes('disabled')).toBeDefined()
     await vi.waitFor(() => expect(wrapper.findAllComponents(ColorPicker)).toHaveLength(3), {
       timeout: 5000,
     })
@@ -113,7 +187,7 @@ describe('waveform annotation controls', () => {
     colorPickers[1].vm.$emit('update:pureColor', 'rgba(51, 51, 51, 0.8)')
     colorPickers[2].vm.$emit('update:pureColor', 'rgba(255, 255, 255, 0.5)')
     await wrapper.vm.$nextTick()
-    await wrapper.get('button.is-primary').trigger('click')
+    await wrapper.get('button.ant-btn-primary').trigger('click')
 
     const emitted = wrapper.emitted('confirm')?.[0]?.[0] as
       | {
@@ -133,7 +207,7 @@ describe('waveform annotation controls', () => {
   })
 
   it('formats annotation coordinates using the selected display context', () => {
-    const wrapper = mount(WaveformAnnotationEditor, {
+    const wrapper = mountEditor({
       props: {
         annotation: { id: 'note', seriesId: 'series', x: 1, y: 0.0000001, text: '说明' },
         mode: 'edit',
@@ -142,13 +216,53 @@ describe('waveform annotation controls', () => {
     })
 
     const coordinates = wrapper.get('.waveform-annotation-editor__coordinates').text()
-    expect(coordinates).toContain('X (s)1.000')
+    expect(coordinates).toContain('X1.000')
     expect(coordinates).toContain('Y0.0000001')
     expect(coordinates).not.toContain('e-')
   })
 
+  it('emits valid manual time input and disables save for invalid input', async () => {
+    const wrapper = mountEditor({
+      props: {
+        annotation: { id: 'note', seriesId: 'series', x: 1, y: 2, text: '说明' },
+        mode: 'edit',
+        timeUnit: 'ms',
+      },
+    })
+    const input = wrapper.getComponent(InputNumber)
+    expect(input.props('controls')).toBe(true)
+    await input.vm.$emit('update:value', 1500)
+    expect(wrapper.emitted('time-change')).toBeUndefined()
+    await input.vm.$emit('blur')
+    expect(wrapper.emitted('time-change')).toEqual([['1500']])
+    await input.vm.$emit('update:value', null)
+    await input.vm.$emit('blur')
+    expect(wrapper.get('[role="alert"]').text()).toBe('请输入有效的时间')
+    expect(wrapper.get('button.ant-btn-primary').attributes('disabled')).toBeDefined()
+  })
+
+  it('shows time validation errors and blocks confirmation', async () => {
+    const wrapper = mountEditor({
+      props: {
+        annotation: { id: 'note', seriesId: 'series', x: 1, y: 2, text: '说明' },
+        mode: 'edit',
+        timeError: '时间超出当前波形范围',
+      },
+    })
+
+    const input = wrapper.getComponent(InputNumber)
+    await input.vm.$emit('blur')
+    expect(
+      wrapper.get('.waveform-annotation-editor__coordinate-input').attributes('aria-invalid'),
+    ).toBe('true')
+    expect(wrapper.get('[role="alert"]').text()).toBe('时间超出当前波形范围')
+    expect(wrapper.get('button.ant-btn-primary').attributes('disabled')).toBeDefined()
+    await wrapper.setProps({ timeError: '' })
+    expect(wrapper.find('[role="alert"]').exists()).toBe(false)
+  })
+
   it('hydrates hexadecimal and rgba annotation colors', async () => {
-    const wrapper = mount(WaveformAnnotationEditor, {
+    const wrapper = mountEditor({
       props: {
         annotation: {
           id: 'colored-note',
@@ -176,7 +290,7 @@ describe('waveform annotation controls', () => {
   })
 
   it('supports modal dismissal and live character counting', async () => {
-    const editor = mount(WaveformAnnotationEditor, {
+    const editor = mountEditor({
       props: {
         annotation: { id: 'note', seriesId: 'a', x: 1, y: 2, text: '原文字' },
         mode: 'edit',
@@ -184,23 +298,23 @@ describe('waveform annotation controls', () => {
     })
 
     expect(editor.get('[role="dialog"]').attributes('aria-modal')).toBe('true')
-    expect(editor.get('h2').text()).toBe('编辑标注')
+    expect(editor.get('.ant-modal-title').text()).toBe('编辑标注')
     await editor.get('textarea').setValue('三字说明')
     expect(editor.get('.waveform-annotation-editor__label-row').text()).toContain('4/40')
 
     await editor.get('textarea').trigger('keydown', { key: 'Escape' })
-    await editor.get('.waveform-annotation-editor').trigger('click')
+    await editor.get('.ant-modal-wrap').trigger('click')
     expect(editor.emitted('cancel')).toHaveLength(2)
   })
 
   it('supports cancellation and context menu actions', async () => {
-    const editor = mount(WaveformAnnotationEditor, {
+    const editor = mountEditor({
       props: {
         annotation: { id: 'note', seriesId: 'a', x: 1, y: 2, text: '原文字' },
         mode: 'edit',
       },
     })
-    await editor.findAll('button')[0].trigger('click')
+    await editor.get('.ant-modal-close').trigger('click')
     expect(editor.emitted('cancel')).toHaveLength(1)
 
     const menu = mount(WaveformAnnotationContextMenu, {
diff --git a/src/components/annotation/markup.test.ts b/src/components/annotation/markup.test.ts
index aab9e3c..4fc5ce8 100644
--- a/src/components/annotation/markup.test.ts
+++ b/src/components/annotation/markup.test.ts
@@ -56,6 +56,20 @@ describe('waveform annotation markup', () => {
     ).toBeNull()
   })
 
+  it('snaps outside and between samples to the nearest complete-data point', () => {
+    const points = [
+      { x: 1, y: 10 },
+      { x: 2, y: 20 },
+      { x: 4, y: 40 },
+    ]
+    expect(findNearestPointByX(points, -10)).toEqual(points[0])
+    expect(findNearestPointByX(points, 3.1)).toEqual(points[2])
+    expect(findNearestPointByX(points, 10)).toEqual(points[2])
+    expect(findNearestPointByX(points, 2)).toEqual(points[1])
+    expect(findNearestPointByX([{ x: 2, y: 20 }], 2.1)).toEqual({ x: 2, y: 20 })
+    expect(findNearestPointByX(points, Number.NaN)).toBeNull()
+  })
+
   it('snaps annotations to nearest sample points while using interpolation for distance calculation', () => {
     const track = createTrack(0, 'series', 0, [
       { x: 0, y: 0 },
@@ -89,14 +103,16 @@ describe('waveform annotation markup', () => {
     expect(interpolateAnnotationPoint(points, 2, 'none')).toEqual({ x: 2, y: 10 })
   })
 
-  it('omits interpolated candidates for point-only series between samples', () => {
+  it('uses the nearest screen-space sample for point-only series', () => {
     const pointOnly = createTrack(0, 'points', 0, [
       { x: 0, y: 2 },
       { x: 2, y: 10 },
     ])
     pointOnly.series.lineType = 'none'
 
-    expect(findAnnotationSeriesCandidates([pointOnly], 1, 100, 50)).toEqual([])
+    expect(findAnnotationSeriesCandidates([pointOnly], 1, 5, 80)).toMatchObject([
+      { point: { x: 0, y: 2 }, screenX: 0, screenY: 80, distance: 5 },
+    ])
   })
 
   it('sorts line candidates by screen distance and keeps series metadata', () => {
diff --git a/src/components/annotation/markup.ts b/src/components/annotation/markup.ts
index 6b2f92c..d015e50 100644
--- a/src/components/annotation/markup.ts
+++ b/src/components/annotation/markup.ts
@@ -25,6 +25,25 @@ export const ANNOTATION_CONNECTOR_LENGTH = 32
 
 const pointBisector = bisector((point: { x: number }) => point.x)
 
+function findNearestPointOnScreen(
+  track: AnnotationTrackLayout,
+  pointerX: number,
+  pointerY: number,
+): { point: { x: number; y: number }; screenX: number; screenY: number; distance: number } | null {
+  let nearest: { point: { x: number; y: number }; screenX: number; screenY: number; distance: number } | null =
+    null
+  for (const point of track.series.points) {
+    if (!Number.isFinite(point.x) || !Number.isFinite(point.y)) continue
+    const screenX = track.xScale(point.x)
+    const screenY = track.top + track.yScale(point.y)
+    const distance = Math.hypot(screenX - pointerX, screenY - pointerY)
+    if (!nearest || distance < nearest.distance) {
+      nearest = { point, screenX, screenY, distance }
+    }
+  }
+  return nearest
+}
+
 export function findNearestPointByX(
   points: Array<{ x: number; y: number }>,
   xValue: number,
@@ -74,6 +93,20 @@ export function findAnnotationSeriesCandidates(
 ): AnnotationSeriesCandidate[] {
   return tracks
     .flatMap((track): AnnotationSeriesCandidate[] => {
+      if (track.series.lineType === 'none') {
+        const nearest = findNearestPointOnScreen(track, pointerX, pointerY)
+        if (!nearest) return []
+        return [
+          {
+            trackIndex: track.index,
+            seriesId: track.series.id,
+            name: track.series.name?.trim() || track.series.id,
+            color: track.series.color || DEFAULT_ANNOTATION_STYLE.borderColor,
+            unit: track.series.unit,
+            ...nearest,
+          },
+        ]
+      }
       const interpolatedPoint = interpolateAnnotationPoint(
         track.series.points,
         xValue,
diff --git a/src/components/annotation/useWaveformChartAnnotations.ts b/src/components/annotation/useWaveformChartAnnotations.ts
index 10c1b5b..3baa457 100644
--- a/src/components/annotation/useWaveformChartAnnotations.ts
+++ b/src/components/annotation/useWaveformChartAnnotations.ts
@@ -1,5 +1,5 @@
 import { pointer, type ScaleLinear } from 'd3'
-import type { ComputedRef, Ref } from 'vue'
+import { ref, type ComputedRef, type Ref } from 'vue'
 
 import type { WaveformAnnotation, WaveformInteractionMode } from '../data/types'
 import { findClosestTrackAtPointer } from '../core/layout'
@@ -9,7 +9,7 @@ import {
   ANNOTATION_AMBIGUITY_DISTANCE,
   ANNOTATION_HIT_RADIUS,
   findAnnotationSeriesCandidates,
-  interpolateAnnotationPoint,
+  findNearestPointByX,
 } from './markup'
 import type {
   AnnotationEditorAnchor,
@@ -78,6 +78,7 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
     activeInteractionMode,
     isPresentationMode,
   } = context
+  const timeError = ref('')
 
   function toggleSeriesVisibility(seriesId: string) {
     if (!chartSeries.value.some((series) => series.id === seriesId)) return
@@ -127,6 +128,7 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
     anchor: AnnotationEditorAnchor,
     candidates: AnnotationSeriesCandidate[],
   ) {
+    timeError.value = ''
     annotationInteraction.openCreate(hit, makeAnnotationId, anchor)
     editorSeriesOptions.value = candidates
     const draft = annotationInteraction.editorDraft.value
@@ -140,7 +142,6 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
       }
     }
   }
-
   function changeDraftSeries(seriesId: string) {
     if (isPresentationMode.value) return
     const draft = annotationInteraction.editorDraft.value
@@ -149,24 +150,61 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
       item.seriesList.some((series) => series.id === seriesId),
     )
     const series = track?.seriesList.find((item) => item.id === seriesId)
-    const point =
-      series && draft
-        ? interpolateAnnotationPoint(series.points, draft.annotation.x, series.lineType)
-        : null
-    if (!draft || !candidate || !track || !point) return
+    const validPoints = series?.points.filter(
+      (item) => Number.isFinite(item.x) && Number.isFinite(item.y),
+    )
+    const point = validPoints && draft ? findNearestPointByX(validPoints, draft.annotation.x) : null
+    if (!draft || !candidate || !track || !validPoints?.length) {
+      timeError.value = '当前波形没有有效数据'
+      return
+    }
+    if (draft.annotation.x < validPoints[0].x || draft.annotation.x > validPoints.at(-1)!.x) {
+      timeError.value = '时间超出当前波形范围'
+      return
+    }
+    timeError.value = ''
     draft.annotation = {
       ...draft.annotation,
       seriesId,
-      y: point.y,
+      y: point!.y,
       style: { ...draft.annotation.style, borderColor: candidate.color },
     }
   }
-
+  function changeDraftTime(displayValue: string) {
+    if (isPresentationMode.value) return
+    const draft = annotationInteraction.editorDraft.value
+    const displayTime = Number(displayValue)
+    if (!draft || !Number.isFinite(displayTime)) {
+      timeError.value = '请输入有效的时间'
+      return
+    }
+    const rawTime = props.timeUnit === 'ms' ? displayTime / 1000 : displayTime
+    const track = trackLayouts.value.find((item) =>
+      item.seriesList.some((series) => series.id === draft.annotation.seriesId),
+    )
+    const series = track?.seriesList.find((item) => item.id === draft.annotation.seriesId)
+    const validPoints = series?.points.filter(
+      (point) => Number.isFinite(point.x) && Number.isFinite(point.y),
+    )
+    if (!validPoints?.length) {
+      timeError.value = '当前波形没有有效数据'
+      return
+    }
+    const firstX = validPoints[0].x
+    const lastX = validPoints[validPoints.length - 1].x
+    if (rawTime < firstX || rawTime > lastX) {
+      timeError.value = '时间超出当前波形范围'
+      return
+    }
+    const point = findNearestPointByX(validPoints, rawTime)!
+    timeError.value = ''
+    draft.annotation = { ...draft.annotation, x: point.x, y: point.y }
+  }
   function cancelAnnotation() {
+    timeError.value = ''
     annotationInteraction.closeEditor()
     editorSeriesOptions.value = []
   }
-
   function resolveTrackAtPointer(
     pointerX: number,
     pointerY: number,
@@ -292,6 +330,7 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
 
   function editContextAnnotation() {
     if (isPresentationMode.value) return
+    timeError.value = ''
     const menu = annotationInteraction.contextMenu.value
     const annotation = props.annotations.find((item) => item.id === menu?.annotationId)
     if (!annotation) return
@@ -328,7 +367,7 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
   function confirmAnnotation(annotation: WaveformAnnotation) {
     if (isPresentationMode.value) return
     const draft = annotationInteraction.editorDraft.value
-    if (!draft) return
+    if (!draft || timeError.value) return
     if (draft.mode === 'add') {
       emit('update:annotations', [...props.annotations, annotation])
       emit('annotation-create', annotation)
@@ -345,6 +384,8 @@ export function useWaveformChartAnnotations(context: AnnotationContext) {
   return {
     toggleSeriesVisibility,
     changeDraftSeries,
+    changeDraftTime,
+    timeError,
     cancelAnnotation,
     resolveTrackAtPointer,
     handleAnnotationClick,
diff --git a/src/components/core/constants.test.ts b/src/components/core/constants.test.ts
new file mode 100644
index 0000000..6afff78
--- /dev/null
+++ b/src/components/core/constants.test.ts
@@ -0,0 +1,29 @@
+import { describe, expect, it } from 'vitest'
+
+import { channelColors } from './constants'
+
+describe('channelColors', () => {
+  it('contains the referenced dark palette followed by twenty supplemental colors', () => {
+    expect(channelColors).toHaveLength(30)
+    expect(channelColors.slice(0, 10)).toEqual([
+      '#0960bd',
+      '#ff7f0e',
+      '#2ca02c',
+      '#d62728',
+      '#9467bd',
+      '#8c564b',
+      '#e377c2',
+      '#7f7f7f',
+      '#bcbd22',
+      '#17becf',
+    ])
+    expect(new Set(channelColors).size).toBe(channelColors.length)
+  })
+
+  it('wraps around after the thirtieth color for automatic series assignment', () => {
+    expect(channelColors[0]).toBe('#0960bd')
+    expect(channelColors[29]).toBe('#31572c')
+    expect(channelColors[30 % channelColors.length]).toBe(channelColors[0])
+    expect(channelColors[31 % channelColors.length]).toBe(channelColors[1])
+  })
+})
diff --git a/src/components/core/constants.ts b/src/components/core/constants.ts
index e0efae3..86bb758 100644
--- a/src/components/core/constants.ts
+++ b/src/components/core/constants.ts
@@ -125,19 +125,41 @@ export const TITLE_LINE_HEIGHT = 1.2
 // ==================== 样式常量 ====================
 
 /**
- * 通道默认颜色列表
+ * 多系列波形的默认颜色列表。
+ *
+ * 颜色保持较深并具备足够辨识度，避免大量系列同时绘制时使用浅色导致线条难以观察。
  */
 export const channelColors = [
   '#0960bd',
   '#ff7f0e',
-  '#389e0d',
-  '#cf1322',
-  '#531dab',
-  '#08979c',
-  '#c41d7f',
-  '#434343',
-  '#7cb305',
-  '#1d39c4',
+  '#2ca02c',
+  '#d62728',
+  '#9467bd',
+  '#8c564b',
+  '#e377c2',
+  '#7f7f7f',
+  '#bcbd22',
+  '#17becf',
+  '#005f73',
+  '#0a9396',
+  '#ae2012',
+  '#bb3e03',
+  '#ca6702',
+  '#ee9b00',
+  '#9b2226',
+  '#3a0ca3',
+  '#4361ee',
+  '#4895ef',
+  '#560bad',
+  '#7209b7',
+  '#b5179e',
+  '#f72585',
+  '#006d77',
+  '#2f3e46',
+  '#354f52',
+  '#52796f',
+  '#800f2f',
+  '#31572c',
 ]
 
 /**
diff --git a/src/components/waveformChartCases/annotationEditingAndReprojection.test.ts b/src/components/waveformChartCases/annotationEditingAndReprojection.test.ts
index c2fdc73..c976cb2 100644
--- a/src/components/waveformChartCases/annotationEditingAndReprojection.test.ts
+++ b/src/components/waveformChartCases/annotationEditingAndReprojection.test.ts
@@ -1,10 +1,18 @@
-import { flushPromises } from '@vue/test-utils'
+import { DOMWrapper, flushPromises } from '@vue/test-utils'
 import { describe, expect, it } from 'vitest'
 
 import { flushAnimationFrames } from '../../test/setup'
 
 import { mountSizedChart } from '../../test/waveformChart'
 
+function getAnnotationEditor() {
+  const editor = Array.from(document.body.querySelectorAll<HTMLElement>('[role="dialog"]'))
+    .filter((element) => element.closest('.waveform-annotation-editor'))
+    .at(-1)
+  if (!editor) throw new Error('Expected annotation editor modal to be mounted')
+  return new DOMWrapper(editor)
+}
+
 describe('WaveformChart', () => {
   it('edits and immediately deletes existing annotations without mutating props', async () => {
     const sourceAnnotation = {
@@ -31,8 +39,10 @@ describe('WaveformChart', () => {
     })
     await wrapper.get('.waveform-annotation-context-menu button').trigger('click')
     await flushPromises()
-    await wrapper.get('textarea[aria-label="标注文本"]').setValue('新文字')
-    await wrapper.get('.waveform-annotation-editor button.is-primary').trigger('click')
+    const editor = getAnnotationEditor()
+    await editor.get('textarea[aria-label="标注文本"]').setValue('新文字')
+    await editor.get('button.ant-btn-primary').trigger('click')
+    await flushPromises()
 
     const updated = wrapper.emitted('update:annotations')?.at(-1)?.[0] as
       Array<{ text: string }> | undefined
diff --git a/src/components/waveformChartCases/dataAndHoverPerformance.test.ts b/src/components/waveformChartCases/dataAndHoverPerformance.test.ts
index 5dc7bf5..ebf4817 100644
--- a/src/components/waveformChartCases/dataAndHoverPerformance.test.ts
+++ b/src/components/waveformChartCases/dataAndHoverPerformance.test.ts
@@ -189,6 +189,46 @@ describe('WaveformChart', () => {
     expect(wrapper.emitted('point-hover')?.at(-1)).toEqual([null])
   })
 
+  it('clears hover when the pointer leaves the chart and restores it only after a new plot move', async () => {
+    const wrapper = await mountSizedChart(
+      {
+        kind: 'points',
+        points: [
+          { x: 0, y: 0 },
+          { x: 1, y: 5 },
+        ],
+      },
+      { grid: { rowCount: 1, columnCount: 1 } },
+    )
+    const overlay = wrapper.get('.waveform-chart__overlay')
+    const overlayWidth = Number(overlay.attributes('width'))
+    Object.defineProperty(overlay.element, 'getBoundingClientRect', {
+      value: () => ({ left: 0, top: 0, width: overlayWidth, height: 290 }),
+    })
+
+    overlay.element.dispatchEvent(
+      new MouseEvent('pointermove', { clientX: overlayWidth, clientY: 120, bubbles: true }),
+    )
+    flushAnimationFrames()
+    await flushPromises()
+    expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(true)
+
+    await wrapper.trigger('pointerleave')
+    expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(false)
+    expect(wrapper.find('.waveform-chart__crosshair').exists()).toBe(false)
+    expect(wrapper.emitted('point-hover')?.at(-1)).toEqual([null])
+
+    await wrapper.trigger('pointerenter')
+    expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(false)
+
+    overlay.element.dispatchEvent(
+      new MouseEvent('pointermove', { clientX: 0, clientY: 120, bubbles: true }),
+    )
+    flushAnimationFrames()
+    await flushPromises()
+    expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(true)
+  })
+
   it('hides the numeric tooltip and crosshair when showTooltip is disabled', async () => {
     const wrapper = await mountSizedChart(
       {
diff --git a/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts b/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts
index 0402558..e8d1555 100644
--- a/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts
+++ b/src/components/waveformChartCases/interactionAndAnnotationCreation.test.ts
@@ -1,10 +1,18 @@
-import { flushPromises } from '@vue/test-utils'
+import { DOMWrapper, flushPromises } from '@vue/test-utils'
 import { describe, expect, it } from 'vitest'
 
 import { flushAnimationFrames, pendingAnimationFrameCount } from '../../test/setup'
 
 import { mountSizedChart } from '../../test/waveformChart'
 
+function getAnnotationEditor() {
+  const editor = Array.from(document.body.querySelectorAll<HTMLElement>('[role="dialog"]'))
+    .filter((element) => element.closest('.waveform-annotation-editor'))
+    .at(-1)
+  if (!editor) throw new Error('Expected annotation editor modal to be mounted')
+  return new DOMWrapper(editor)
+}
+
 describe('WaveformChart', () => {
   it('zooms only the active independent track and resets when the mode changes', async () => {
     const wrapper = await mountSizedChart({
@@ -172,9 +180,10 @@ describe('WaveformChart', () => {
     )
     await flushPromises()
 
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(true)
-    await wrapper.get('textarea[aria-label="标注文本"]').setValue('峰值点')
-    await wrapper.get('.waveform-annotation-editor button.is-primary').trigger('click')
+    const editor = getAnnotationEditor()
+    await editor.get('textarea[aria-label="标注文本"]').setValue('峰值点')
+    await editor.get('button.ant-btn-primary').trigger('click')
+    await flushPromises()
 
     const annotations = wrapper.emitted('update:annotations')?.at(-1)?.[0] as
       Array<{ seriesId: string; x: number; y: number; text: string }> | undefined
@@ -209,10 +218,10 @@ describe('WaveformChart', () => {
       }),
     )
     await flushPromises()
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(true)
-    expect(wrapper.get('.waveform-annotation-editor').attributes('aria-modal')).toBe('true')
-    expect(wrapper.find('.waveform-annotation-editor__panel').exists()).toBe(true)
-    const textarea = wrapper.get('textarea[aria-label="标注文本"]')
+    const editor = getAnnotationEditor()
+    expect(editor.attributes('role')).toBe('dialog')
+    expect(editor.find('.waveform-annotation-editor__content').exists()).toBe(true)
+    const textarea = editor.get('textarea[aria-label="标注文本"]')
     const textareaContextMenu = new MouseEvent('contextmenu', {
       bubbles: true,
       cancelable: true,
@@ -220,7 +229,8 @@ describe('WaveformChart', () => {
     expect(textarea.element.dispatchEvent(textareaContextMenu)).toBe(true)
     expect(textareaContextMenu.defaultPrevented).toBe(false)
     await textarea.setValue('右键标注')
-    await wrapper.get('.waveform-annotation-editor button.is-primary').trigger('click')
+    await editor.get('button.ant-btn-primary').trigger('click')
+    await flushPromises()
 
     // Annotation snaps to nearest sample point (x=1, y=5)
     expect(wrapper.emitted('update:annotations')?.at(-1)?.[0]).toMatchObject([
@@ -278,20 +288,20 @@ describe('WaveformChart', () => {
     )
     await flushPromises()
     expect(
-      wrapper
-        .find('select[aria-label="选择标注波形"]')
+      getAnnotationEditor()
+        .get('select[aria-label="选择标注波形"]')
         .findAll('option')
         .map((item) => item.text()),
     ).toEqual(['通道 A'])
 
-    await wrapper.get('button[aria-label="关闭标注编辑器"]').trigger('click')
+    await getAnnotationEditor().get('.ant-modal-close').trigger('click')
     overlays[0].element.dispatchEvent(
       new MouseEvent('contextmenu', { clientX: 356, clientY: 230, bubbles: true }),
     )
     await flushPromises()
     expect(
-      wrapper
-        .find('select[aria-label="选择标注波形"]')
+      getAnnotationEditor()
+        .get('select[aria-label="选择标注波形"]')
         .findAll('option')
         .map((item) => item.text()),
     ).toEqual(['通道 B'])
diff --git a/src/components/waveformChartCases/legendVisibility.test.ts b/src/components/waveformChartCases/legendVisibility.test.ts
index 9f1dc9d..014e803 100644
--- a/src/components/waveformChartCases/legendVisibility.test.ts
+++ b/src/components/waveformChartCases/legendVisibility.test.ts
@@ -7,6 +7,14 @@ import WaveformChartView from '../WaveformChartView.vue'
 
 import { gridSeries, mountSizedChart, visibilitySeries } from '../../test/waveformChart'
 
+function annotationEditorExists() {
+  return Boolean(
+    Array.from(document.body.querySelectorAll<HTMLElement>('[role="dialog"]'))
+      .filter((element) => element.closest('.waveform-annotation-editor'))
+      .at(-1),
+  )
+}
+
 describe('WaveformChart', () => {
   it('resolves legend positions by stable track id across pages', async () => {
     const wrapper = await mountSizedChart(
@@ -273,7 +281,7 @@ describe('WaveformChart', () => {
     )
     flushAnimationFrames()
     await flushPromises()
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(true)
+    expect(annotationEditorExists()).toBe(true)
 
     const controller = wrapper.getComponent(WaveformChartView).props('controller') as unknown as {
       annotationInteraction: { editorDraft: { value: { annotation: { seriesId: string } } | null } }
@@ -287,7 +295,7 @@ describe('WaveformChart', () => {
     expect(item).toBeDefined()
     await item!.trigger('click')
     await flushPromises()
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(false)
+    expect(annotationEditorExists()).toBe(false)
   })
 
   it('renders independent cells with separate x axes and overlays', async () => {
diff --git a/src/components/waveformChartCases/multiAxisAndPagination.test.ts b/src/components/waveformChartCases/multiAxisAndPagination.test.ts
index 2a04a84..1812090 100644
--- a/src/components/waveformChartCases/multiAxisAndPagination.test.ts
+++ b/src/components/waveformChartCases/multiAxisAndPagination.test.ts
@@ -208,7 +208,7 @@ describe('WaveformChart', () => {
       legend
         .findAll('.waveform-legend__swatch')
         .map((swatch) => swatch.get('path').attributes('stroke')),
-    ).toEqual(['#0960bd', '#389e0d'])
+    ).toEqual(['#0960bd', '#2ca02c'])
     expect(wrapper.findAll('.waveform-chart__watermark').map((item) => item.text())).toEqual([
       '1',
       '2',
diff --git a/src/components/waveformChartCases/presentationMode.test.ts b/src/components/waveformChartCases/presentationMode.test.ts
index adc8f19..140197d 100644
--- a/src/components/waveformChartCases/presentationMode.test.ts
+++ b/src/components/waveformChartCases/presentationMode.test.ts
@@ -5,6 +5,14 @@ import { flushAnimationFrames } from '../../test/setup'
 import { mountSizedChart } from '../../test/waveformChart'
 import type { WaveformData, WaveformDisplayMode } from '../data/types'
 
+function annotationEditorExists() {
+  return Boolean(
+    Array.from(document.body.querySelectorAll<HTMLElement>('[role="dialog"]'))
+      .filter((element) => element.closest('.waveform-annotation-editor'))
+      .at(-1),
+  )
+}
+
 const presentationData: WaveformData = {
   kind: 'series',
   series: [
@@ -282,13 +290,13 @@ describe('WaveformChart presentation mode', () => {
       }),
     )
     await flushPromises()
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(true)
+    expect(annotationEditorExists()).toBe(true)
 
     await wrapper.setProps({ presentationMode: true })
     await flushPromises()
 
     expect(wrapper.find('.waveform-chart__tooltip').exists()).toBe(false)
-    expect(wrapper.find('.waveform-annotation-editor').exists()).toBe(false)
+    expect(annotationEditorExists()).toBe(false)
     expect(wrapper.emitted('point-hover')?.at(-1)).toEqual([null])
 
     await wrapper.setProps({ presentationMode: false })
diff --git a/src/components/waveformChartCases/renderingStyles.test.ts b/src/components/waveformChartCases/renderingStyles.test.ts
index 10e8218..4704844 100644
--- a/src/components/waveformChartCases/renderingStyles.test.ts
+++ b/src/components/waveformChartCases/renderingStyles.test.ts
@@ -181,7 +181,7 @@ describe('WaveformChart', () => {
     ])
     expect(stepSwatchPaths[0]?.attributes()).toMatchObject({
       d: 'M1 8H25',
-      stroke: '#389e0d',
+      stroke: '#2ca02c',
       'stroke-width': '1.5',
     })
     expect(stepSwatchPaths[1]?.attributes()).toMatchObject({
diff --git a/src/components/waveformChartCases/xDomainStrategy.test.ts b/src/components/waveformChartCases/xDomainStrategy.test.ts
index 6edec71..99211cb 100644
--- a/src/components/waveformChartCases/xDomainStrategy.test.ts
+++ b/src/components/waveformChartCases/xDomainStrategy.test.ts
@@ -93,4 +93,64 @@ describe('WaveformChart x domain strategy', () => {
     expect(tracks[1]?.get('.waveform-chart__axis-endpoint--start').text()).toBe('10000')
     expect(tracks[1]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('15000')
   })
+
+  it('keeps an explicit viewport wider than the data and leaves uncovered time blank', async () => {
+    const wrapper = await mountSizedChart(
+      {
+        kind: 'points',
+        points: [
+          { x: 0, y: 0 },
+          { x: 10, y: 1 },
+        ],
+      },
+      { timeUnit: 's', initialXDomain: [-5, 20] },
+    )
+
+    const track = wrapper.get('.waveform-chart__track')
+    const width = Number(track.attributes('data-track-width'))
+    const path = track.get('.waveform-chart__line').attributes('d') ?? ''
+    const xCoordinates = Array.from(path.matchAll(/(?:M|L)([\d.-]+)/g)).map((match) =>
+      Number(match[1]),
+    )
+
+    expect(track.get('.waveform-chart__axis-endpoint--start').text()).toBe('-5')
+    expect(track.get('.waveform-chart__axis-endpoint--end').text()).toBe('20')
+    expect(xCoordinates.length).toBeGreaterThan(0)
+    expect(Math.min(...xCoordinates)).toBeGreaterThanOrEqual(0)
+    expect(Math.max(...xCoordinates)).toBeLessThanOrEqual(width)
+  })
+
+  it('applies independent explicit viewports per track, including empty time regions', async () => {
+    const wrapper = await mountSizedChart(
+      {
+        kind: 'series',
+        series: [
+          {
+            id: 'first',
+            name: '第一轨',
+            data: { kind: 'points', points: [{ x: 0, y: 0 }, { x: 10, y: 1 }] },
+          },
+          {
+            id: 'second',
+            name: '第二轨',
+            data: { kind: 'points', points: [{ x: 100, y: 0 }, { x: 110, y: 1 }] },
+          },
+        ],
+      },
+      {
+        displayMode: 'independent',
+        grid: { rowCount: 1, columnCount: 2 },
+        timeUnit: 's',
+        initialXDomains: { first: [-5, 20], second: [95, 120] },
+      },
+    )
+
+    const tracks = wrapper.findAll('.waveform-chart__track')
+    expect(tracks[0]?.get('.waveform-chart__axis-endpoint--start').text()).toBe('-5')
+    expect(tracks[0]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('20')
+    expect(tracks[1]?.get('.waveform-chart__axis-endpoint--start').text()).toBe('95')
+    expect(tracks[1]?.get('.waveform-chart__axis-endpoint--end').text()).toBe('120')
+    expect(tracks[0]?.find('.waveform-chart__line').exists()).toBe(true)
+    expect(tracks[1]?.find('.waveform-chart__line').exists()).toBe(true)
+  })
 })