diff --git a/src/components/AppTagInput.vue b/src/components/AppTagInput.vue
new file mode 100644
index 0000000..aadc419
--- /dev/null
+++ b/src/components/AppTagInput.vue
@@ -0,0 +1,177 @@
+<script setup lang="ts">
+import { ref, computed, onBeforeUnmount, nextTick } from 'vue'
+import { X, Plus } from 'lucide-vue-next'
+import { useTagsStore } from '../stores/tags'
+import { computeDropdownPosition } from '../utils/dropdown'
+
+interface Props {
+  modelValue: number[]
+}
+
+const props = defineProps<Props>()
+const emit = defineEmits<{
+  'update:modelValue': [value: number[]]
+}>()
+
+const tagsStore = useTagsStore()
+
+const isOpen = ref(false)
+const searchQuery = ref('')
+const triggerRef = ref<HTMLDivElement | null>(null)
+const panelRef = ref<HTMLDivElement | null>(null)
+const panelStyle = ref<Record<string, string>>({})
+const inputRef = ref<HTMLInputElement | null>(null)
+
+const selectedTags = computed(() => {
+  return tagsStore.tags.filter(t => t.id && props.modelValue.includes(t.id))
+})
+
+const filteredTags = computed(() => {
+  const q = searchQuery.value.toLowerCase()
+  return tagsStore.tags.filter(t => {
+    if (t.id && props.modelValue.includes(t.id)) return false
+    if (q && !t.name.toLowerCase().includes(q)) return false
+    return true
+  })
+})
+
+const showCreateOption = computed(() => {
+  if (!searchQuery.value.trim()) return false
+  return !tagsStore.tags.some(t => t.name.toLowerCase() === searchQuery.value.trim().toLowerCase())
+})
+
+function toggleTag(tagId: number) {
+  const current = [...props.modelValue]
+  const index = current.indexOf(tagId)
+  if (index >= 0) {
+    current.splice(index, 1)
+  } else {
+    current.push(tagId)
+  }
+  emit('update:modelValue', current)
+}
+
+function removeTag(tagId: number) {
+  emit('update:modelValue', props.modelValue.filter(id => id !== tagId))
+}
+
+async function createAndAdd() {
+  const name = searchQuery.value.trim()
+  if (!name) return
+  const colors = ['#3B82F6', '#8B5CF6', '#EC4899', '#10B981', '#EF4444', '#06B6D4', '#F59E0B', '#6B7280']
+  const color = colors[tagsStore.tags.length % colors.length]
+  const id = await tagsStore.createTag({ name, color })
+  if (id) {
+    emit('update:modelValue', [...props.modelValue, id])
+    searchQuery.value = ''
+  }
+}
+
+function updatePosition() {
+  if (!triggerRef.value) return
+  panelStyle.value = computeDropdownPosition(triggerRef.value, { minWidth: 200, estimatedHeight: 200 })
+}
+
+function open() {
+  isOpen.value = true
+  searchQuery.value = ''
+  updatePosition()
+  nextTick(() => inputRef.value?.focus())
+  document.addEventListener('click', onClickOutside, true)
+  document.addEventListener('scroll', onScrollOrResize, true)
+  window.addEventListener('resize', onScrollOrResize)
+}
+
+function close() {
+  isOpen.value = false
+  document.removeEventListener('click', onClickOutside, true)
+  document.removeEventListener('scroll', onScrollOrResize, true)
+  window.removeEventListener('resize', onScrollOrResize)
+}
+
+function onClickOutside(e: MouseEvent) {
+  const target = e.target as Node
+  if (triggerRef.value?.contains(target) || panelRef.value?.contains(target)) return
+  close()
+}
+
+function onScrollOrResize() {
+  if (isOpen.value) updatePosition()
+}
+
+onBeforeUnmount(() => {
+  document.removeEventListener('click', onClickOutside, true)
+  document.removeEventListener('scroll', onScrollOrResize, true)
+  window.removeEventListener('resize', onScrollOrResize)
+})
+</script>
+
+<template>
+  <div ref="triggerRef" class="relative">
+    <!-- Selected tags + add button -->
+    <div class="flex flex-wrap items-center gap-1.5">
+      <span
+        v-for="tag in selectedTags"
+        :key="tag.id"
+        class="inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-[0.6875rem] text-text-primary"
+        :style="{ backgroundColor: tag.color + '22', borderColor: tag.color + '44', border: '1px solid' }"
+      >
+        <span class="w-1.5 h-1.5 rounded-full" :style="{ backgroundColor: tag.color }" />
+        {{ tag.name }}
+        <button @click.stop="removeTag(tag.id!)" class="ml-0.5 hover:text-status-error">
+          <X class="w-2.5 h-2.5" />
+        </button>
+      </span>
+      <button
+        type="button"
+        @click="isOpen ? close() : open()"
+        class="inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-[0.6875rem] text-text-tertiary border border-border-subtle hover:text-text-secondary hover:border-border-visible transition-colors"
+      >
+        <Plus class="w-3 h-3" />
+        Tag
+      </button>
+    </div>
+
+    <!-- Dropdown -->
+    <Teleport to="body">
+      <div
+        v-if="isOpen"
+        ref="panelRef"
+        :style="panelStyle"
+        class="bg-bg-surface border border-border-visible rounded-xl shadow-[0_4px_24px_rgba(0,0,0,0.4)] overflow-hidden animate-dropdown-enter"
+      >
+        <div class="px-2 pt-2 pb-1">
+          <input
+            ref="inputRef"
+            v-model="searchQuery"
+            type="text"
+            class="w-full px-2.5 py-1.5 bg-bg-inset border border-border-subtle rounded-lg text-[0.75rem] text-text-primary placeholder-text-tertiary focus:outline-none focus:border-border-visible"
+            placeholder="Search or create tag..."
+          />
+        </div>
+        <div class="max-h-[160px] overflow-y-auto py-1">
+          <div
+            v-for="tag in filteredTags"
+            :key="tag.id"
+            @click="toggleTag(tag.id!); searchQuery = ''"
+            class="flex items-center gap-2 px-3 py-1.5 cursor-pointer hover:bg-bg-elevated transition-colors"
+          >
+            <span class="w-2 h-2 rounded-full" :style="{ backgroundColor: tag.color }" />
+            <span class="text-[0.75rem] text-text-primary">{{ tag.name }}</span>
+          </div>
+          <div
+            v-if="showCreateOption"
+            @click="createAndAdd"
+            class="flex items-center gap-2 px-3 py-1.5 cursor-pointer hover:bg-bg-elevated transition-colors text-accent-text"
+          >
+            <Plus class="w-3 h-3" />
+            <span class="text-[0.75rem]">Create "{{ searchQuery.trim() }}"</span>
+          </div>
+          <div v-if="filteredTags.length === 0 && !showCreateOption" class="px-3 py-3 text-center text-[0.75rem] text-text-tertiary">
+            No tags found
+          </div>
+        </div>
+      </div>
+    </Teleport>
+  </div>
+</template>