#171

backend/app/controllers/posts_controller.rb

@@ -173,8 +173,8 @@ class PostsController < ApplicationController
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
 
-    force = truthy_param?(params[:force])
+    force = bool?(:force)
-    merge = truthy_param?(params[:merge])
+    merge = bool?(:merge)
     return head :bad_request if force && merge
 
     base_version_no = nil
@@ -201,15 +201,14 @@ class PostsController < ApplicationController
         base_snapshot = post_snapshot_from_version(base_version)
         current_snapshot = post_snapshot_from_record(post)
       end
-      incoming_snapshot = post_incoming_snapshot(post,
+      incoming_snapshot = post_incoming_snapshot(title:,
-                                                 title:,
                                                  original_created_from:,
                                                  original_created_before:,
                                                  tag_names:,
                                                  parent_post_ids:)
 
       snapshot_to_apply =
-          if post.version_no == base_version_no || force
+          if force || post.version_no == base_version_no || current_snapshot == base_snapshot
             incoming_snapshot
           else
             changes = post_snapshot_changes(base_snapshot, current_snapshot, incoming_snapshot)
@@ -448,30 +447,36 @@ class PostsController < ApplicationController
     version_no
   end
 
-  def truthy_param?(value) = ActiveModel::Type::Boolean.new.cast(value)
-
   def post_snapshot_from_version version
     { title: version.title,
       original_created_from: snapshot_time(version.original_created_from),
       original_created_before: snapshot_time(version.original_created_before),
-      tag_names: version.tags.to_s.split.filter { !(_1.start_with?('nico:')) }.sort,
+      tag_names: editable_tag_names_from_version(version),
       parent_post_ids: snapshot_parent_post_ids_from_version(version) }
   end
 
+  def editable_tag_names_from_version version
+    version.tags.to_s.split.reject { |name| name.downcase.start_with?('nico:') }.sort
+  end
+
   def post_snapshot_from_record post
     { title: post.title,
       original_created_from: snapshot_time(post.original_created_from),
       original_created_before: snapshot_time(post.original_created_before),
-      tag_names: post.tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name'),
+      tag_names: editable_tag_names_from_post(post),
       parent_post_ids: post.parent_posts.order(:id).pluck(:id) }
   end
 
-  def post_incoming_snapshot post, title:, original_created_from:, original_created_before:,
+  def editable_tag_names_from_post post
-                                   tag_names:, parent_post_ids:
+    post.tags.not_nico.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
+  end
+
+  def post_incoming_snapshot title:, original_created_from:, original_created_before:,
+                             tag_names:, parent_post_ids:
     { title:,
       original_created_from: snapshot_time(original_created_from),
       original_created_before: snapshot_time(original_created_before),
-      tag_names: incoming_tag_names_for_snapshot(post, tag_names),
+      tag_names: incoming_tag_names_for_snapshot(tag_names),
       parent_post_ids: parent_post_ids.sort }
   end
 
@@ -494,44 +499,10 @@ class PostsController < ApplicationController
     value.to_s
   end
 
-  def incoming_tag_names_for_snapshot post, raw_tag_names
+  def incoming_tag_names_for_snapshot raw_tag_names
-    manual_names = normalised_manual_tag_names_for_snapshot(raw_tag_names)
+    tags = Tag.normalise_tags!(raw_tag_names, with_tagme: false)
 
-    existing_tags =
+    Tag.expand_parent_tags(tags).map(&:name).uniq.sort
-        Tag
-        .joins(:tag_name)
-        .where(tag_names: { name: manual_names })
-        .to_a
-
-    expanded_names = Tag.expand_parent_tags(existing_tags).map(&:name)
-
-    (manual_names + expanded_names).uniq.sort
-  end
-
-  def normalised_manual_tag_names_for_snapshot raw_tag_names
-    if raw_tag_names.any? { |name| name.downcase.start_with?('nico:') }
-      raise Tag::NicoTagNormalisationError
-    end
-
-    pairs = raw_tag_names.map do |raw_name|
-      prefix, category =
-          Tag::CATEGORY_PREFIXES.find { |p, _| raw_name.downcase.start_with?(p) } || ['', nil]
-
-      name = TagName.canonicalise(raw_name.sub(/\A#{ Regexp.escape(prefix) }/i, '')).first
-
-      [name, category]
-    end
-
-    names = pairs.map(&:first)
-
-    has_deerjikist = pairs.any? do |name, category|
-      category == :deerjikist ||
-          Tag.joins(:tag_name).where(category: :deerjikist, tag_names: { name: }).exists?
-    end
-
-    names << Tag.no_deerjikist.name unless has_deerjikist
-
-    names.uniq.sort
   end
 
   def post_conflict_json post:, base_version_no:, base_snapshot:,
@@ -618,29 +589,53 @@ class PostsController < ApplicationController
                  original_created_from: snapshot[:original_created_from],
                  original_created_before: snapshot[:original_created_before])
 
-    tags = Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false)
+    editable_tags = Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false)
-    TagVersioning.record_tag_snapshots!(tags, created_by_user: current_user)
+    TagVersioning.record_tag_snapshots!(editable_tags, created_by_user: current_user)
 
+    readonly_tags = post.tags.nico.to_a
+
+    tags = readonly_tags + editable_tags
     tags = Tag.expand_parent_tags(tags)
-    sync_post_tags!(post, tags)
 
+    sync_post_tags!(post, tags)
     sync_parent_posts!(post, snapshot[:parent_post_ids])
 
     PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
   end
 
   def merge_post_snapshots base_snapshot, current_snapshot, incoming_snapshot
-    [:title, :original_created_from, :original_created_before, :tag_names, :parent_post_ids].map {
+    [:title, :original_created_from, :original_created_before].map {
-      [_1, merge_scaler_snapshot_value(base_snapshot[_1],
+      [_1, merge_scalar_snapshot_value(base_snapshot[_1],
                                        current_snapshot[_1],
                                        incoming_snapshot[_1])]
-    }.to_h
+    }.to_h.merge([:tag_names, :parent_post_ids].map {
+      [_1, merge_set_snapshot_value(base_snapshot[_1],
+                                    current_snapshot[_1],
+                                    incoming_snapshot[_1])]
+    }.to_h)
   end
 
-  def merge_scaler_snapshot_value base, current, mine
+  def merge_scalar_snapshot_value base, current, mine
     return mine if current == base
     return current if mine == base || current == mine
 
     raise ArgumentError, '競合してゐる項目はマージできません．'
   end
+
+  def merge_set_snapshot_value base, current, mine
+    base = base.to_a
+    current = current.to_a
+    mine = mine.to_a
+
+    added_by_current = current - base
+    removed_by_current = base - current
+    added_by_me = mine - base
+    removed_by_me = base - mine
+
+    merged = base + added_by_current + added_by_me
+    merged -= removed_by_current
+    merged -= removed_by_me
+
+    merged.uniq.sort
+  end
 end

backend/app/models/post.rb

@@ -28,6 +28,8 @@ class Post < ApplicationRecord
 
   has_one_attached :thumbnail
 
+  attribute :version_no, :integer, default: 1
+
   before_validation :normalise_url
 
   validates :url, presence: true, uniqueness: true

backend/app/models/tag.rb

@@ -40,6 +40,8 @@ class Tag < ApplicationRecord
   belongs_to :tag_name
   delegate :wiki_page, to: :tag_name
 
+  attribute :version_no, :integer, default: 1
+
   delegate :name, to: :tag_name, allow_nil: true
   validates :tag_name, presence: true
 
@@ -136,7 +138,6 @@ class Tag < ApplicationRecord
     tn = tn.canonical if tn.canonical_id?
 
     Tag.find_undiscard_or_create_by!(tag_name_id: tn.id) do |t|
-      t.version_no = TagVersion.where(tag_id: t.id).order(version_no: :desc).first || 1
       t.category = category
     end
   rescue ActiveRecord::RecordNotUnique

backend/app/models/wiki_page.rb

@@ -15,6 +15,8 @@ class WikiPage < ApplicationRecord
 
   has_many :wiki_versions
 
+  attribute :version_no, :integer, default: 1
+
   belongs_to :tag_name
   validates :tag_name, presence: true
   validates :body, presence: true

frontend/src/components/PostEditForm.tsx

@@ -8,7 +8,7 @@ import { Button } from '@/components/ui/button'
 import { toast } from '@/components/ui/use-toast'
 import { updatePost } from '@/lib/posts'
 
-import type { FC } from 'react'
+import type { FC, FormEvent } from 'react'
 
 import type { Post, Tag } from '@/types'
 
@@ -33,6 +33,7 @@ type Props = { post:    Post
 
 
 export default (({ post, onSave }: Props) => {
+  const [disabled, setDisabled] = useState (false)
   const [originalCreatedBefore, setOriginalCreatedBefore] =
       useState<string | null> (post.originalCreatedBefore)
   const [originalCreatedFrom, setOriginalCreatedFrom] =
@@ -61,7 +62,9 @@ export default (({ post, onSave }: Props) => {
     }
     catch (e)
     {
-      if (e.response.status !== 409)
+      const response = (e as any)?.response
+
+      if (response?.status !== 409)
 	{
 	  toast ({ description: '更新はできなかったよ……' })
 	  return
@@ -74,7 +77,7 @@ export default (({ post, onSave }: Props) => {
 		<p>ほかの耕作員が先に更新してゐます．</p>
 		<p>現在の変更をどう扱ひますか?</p>
 	      </div>),
-	  choices: [{ value: 'merge', label: '差分をマージ' },
+	  choices: [...(response?.data?.mergeable ? [{ value: 'merge', label: '差分をマージ' }] : []),
 		    { value: 'overwrite', label: '強制上書き', variant: 'danger' }] })
 
       if (action === 'merge')
@@ -96,12 +99,14 @@ export default (({ post, onSave }: Props) => {
     }
   }
 
-  const handleSubmit = async e => {
+  const handleSubmit = async (e: FormEvent) => {
     e.preventDefault ()
 
+    setDisabled (true)
     await update ({ id: post.id, title, tags, parentPostIds,
 		    originalCreatedFrom, originalCreatedBefore },
 		  { baseVersionNo: post.versionNo })
+    setDisabled (false)
   }
 
   useEffect (() => {
@@ -113,10 +118,12 @@ export default (({ post, onSave }: Props) => {
 	{/* タイトル */}
 	<div>
 	  <Label>タイトル</Label>
-	  <input type="text"
+	  <input
-		 className="w-full border rounded p-2"
+	      type="text"
-		 value={title ?? ''}
+	      disabled={disabled}
-		 onChange={ev => setTitle (ev.target.value)}/>
+	      className="w-full border rounded p-2"
+	      value={title ?? ''}
+	      onChange={ev => setTitle (ev.target.value)}/>
 	</div>
 
 	{/* 親投稿 */}
@@ -124,24 +131,32 @@ export default (({ post, onSave }: Props) => {
 	  <Label>親投稿</Label>
 	  <input
 	      type="text"
+	      disabled={disabled}
 	      value={parentPostIds}
 	      onChange={e => setParentPostIds (e.target.value)}
 	      className="w-full border p-2 rounded"/>
 	</div>
 
 	{/* タグ */}
-	<PostFormTagsArea tags={tags} setTags={setTags}/>
+	<PostFormTagsArea
+	    disabled={disabled}
+	    tags={tags}
+	    setTags={setTags}/>
 
 	{/* オリジナルの作成日時 */}
 	<PostOriginalCreatedTimeField
+	    disabled={disabled}
 	    originalCreatedFrom={originalCreatedFrom}
 	    setOriginalCreatedFrom={setOriginalCreatedFrom}
 	    originalCreatedBefore={originalCreatedBefore}
 	    setOriginalCreatedBefore={setOriginalCreatedBefore}/>
 
 	{/* 送信 */}
-	<Button onClick={handleSubmit}
+	<Button
-		className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
+	    type="submit"
+	    disabled={disabled}
+	    onClick={handleSubmit}
+	    className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
 	  更新
 	</Button>
       </div>)

frontend/src/components/PostFormTagsArea.tsx

@@ -7,7 +7,7 @@ import Label from '@/components/common/Label'
 import TextArea from '@/components/common/TextArea'
 import { apiGet } from '@/lib/api'
 
-import type { FC, SyntheticEvent } from 'react'
+import type { ComponentPropsWithoutRef, FC, SyntheticEvent } from 'react'
 
 import type { Tag } from '@/types'
 
@@ -31,12 +31,13 @@ const replaceToken = (value: string, start: number, end: number, text: string) =
     `${ value.slice (0, start) }${ text }${ value.slice (end) }`
 
 
-type Props = {
+type Props =
-    tags:     string
+    & { tags:     string
-    setTags:  (tags: string) => void }
+	setTags:  (tags: string) => void }
+    & ComponentPropsWithoutRef<'textarea'>
 
 
-export default (({ tags, setTags }: Props) => {
+export default (({ tags, setTags, ...rest }: Props) => {
   const ref = useRef<HTMLTextAreaElement> (null)
 
   const [bounds, setBounds] = useState<{ start: number; end: number }> ({ start: 0, end: 0 })
@@ -87,7 +88,8 @@ export default (({ tags, setTags }: Props) => {
 	    onBlur={() => {
 	      setFocused (false)
 	      setSuggestionsVsbl (false)
-	    }}/>
+	    }}
+	    {...rest}/>
 	{focused && (
 	    <TagSearchBox
 		suggestions={suggestionsVsbl && suggestions.length > 0

frontend/src/components/PostOriginalCreatedTimeField.tsx

@@ -5,13 +5,15 @@ import { Button } from '@/components/ui/button'
 import type { FC } from 'react'
 
 type Props = {
+    disabled?:                boolean
     originalCreatedFrom:      string | null
     setOriginalCreatedFrom:   (x: string | null) => void
     originalCreatedBefore:    string | null
     setOriginalCreatedBefore: (x: string | null) => void }
 
 
-export default (({ originalCreatedFrom,
+export default (({ disabled,
+		   originalCreatedFrom,
 		   setOriginalCreatedFrom,
 		   originalCreatedBefore,
 		   setOriginalCreatedBefore }: Props) => (
@@ -21,6 +23,7 @@ export default (({ originalCreatedFrom,
 	<div className="w-80">
 	  <DateTimeField
 	      className="mr-2"
+	      disabled={disabled ?? false}
 	      value={originalCreatedFrom ?? undefined}
 	      onChange={setOriginalCreatedFrom}
 	      onBlur={ev => {
@@ -40,6 +43,7 @@ export default (({ originalCreatedFrom,
 	<div>
 	  <Button
 	      className="bg-gray-600 text-white rounded"
+	      disabled={disabled}
 	      onClick={() => {
 		setOriginalCreatedFrom (null)
 	      }}>
@@ -51,6 +55,7 @@ export default (({ originalCreatedFrom,
 	<div className="w-80">
 	  <DateTimeField
 	      className="mr-2"
+	      disabled={disabled}
 	      value={originalCreatedBefore ?? undefined}
 	      onChange={setOriginalCreatedBefore}/>
 	  より前
@@ -58,6 +63,7 @@ export default (({ originalCreatedFrom,
 	<div>
 	  <Button
 	      className="bg-gray-600 text-white rounded"
+	      disabled={disabled}
 	      onClick={() => {
 		setOriginalCreatedBefore (null)
 	      }}>

frontend/src/components/TopNav.tsx

@@ -36,12 +36,12 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	  { name: '一覧', to: '/posts' },
 	  { name: '検索', to: '/posts/search' },
 	  { name: '追加', to: '/posts/new' },
-	  { name: '履歴', to: '/posts/changes' },
+	  { name: '全体履歴', to: '/posts/changes' },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:広場' }] },
       { name: 'タグ', to: '/tags', subMenu: [
 	  { name: 'マスタ', to: '/tags' },
 	  { name: 'ニコニコ連携', to: '/tags/nico' },
-	  { name: '履歴', to: '/tags/changes' },
+	  { name: '全体履歴', to: '/tags/changes' },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:タグ' },
 	  { component: <Separator/>, visible: tagFlg },
 	  { name: `広場 (${ postCount || 0 })`,
@@ -53,7 +53,7 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	  { name: '一覧', to: '/materials' },
 	  { name: '検索', to: '/materials/search', visible: false }, 
 	  { name: '追加', to: '/materials/new' },
-	  { name: '履歴', to: '/materials/changes', visible: false },
+	  { name: '全体履歴', to: '/materials/changes', visible: false },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:素材集' }] },
       { name: '上映会', to: '/theatres/1', base: '/theatres', subMenu: [
 	  { name: <>第&thinsp;1&thinsp;会場</>, to: '/theatres/1' },

frontend/src/components/common/DateTimeField.tsx

@@ -2,7 +2,7 @@ import { useEffect, useState } from 'react'
 
 import { cn } from '@/lib/utils'
 
-import type { FC, FocusEvent } from 'react'
+import type { ComponentPropsWithoutRef, FC, FocusEvent } from 'react'
 
 
 const pad = (n: number): string => n.toString ().padStart (2, '0')
@@ -18,14 +18,14 @@ const toDateTimeLocalValue = (d: Date) => {
 }
 
 
-type Props = {
+type Props = Omit<ComponentPropsWithoutRef<'input'>, 'onChange'> & {
     value?:     string
     onChange?:  (isoUTC: string | null) => void
     className?: string
     onBlur?:    (ev: FocusEvent<HTMLInputElement>) => void }
 
 
-export default (({ value, onChange, className, onBlur }: Props) => {
+export default (({ value, onChange, className, onBlur, ...rest }: Props) => {
   const [local, setLocal] = useState ('')
 
   useEffect (() => {
@@ -42,5 +42,6 @@ export default (({ value, onChange, className, onBlur }: Props) => {
 	    setLocal (v)
 	    onChange?.(v ? (new Date (v)).toISOString () : null)
 	  }}
-	  onBlur={onBlur}/>)
+	  onBlur={onBlur}
+	  {...rest}/>)
 }) satisfies FC<Props>

frontend/src/components/ui/dialog.tsx

@@ -37,25 +37,27 @@ const DialogContent = React.forwardRef<
     <DialogOverlay />
     <DialogPrimitive.Content
       ref={ref}
-      className={cn(
+      className={cn (
-	  'fixed left-[50%] top-[50%] z-50 w-[90%] grid max-w-lg',
+	  'fixed left-[50%] top-[50%] z-50 grid w-[calc(100%-2rem)] max-w-lg',
 	  'translate-x-[-50%] translate-y-[-50%]',
-	  'gap-4 border bg-gray-300/80 dark:bg-gray-700/80',
+	  'gap-5 rounded-2xl border border-border',
-	  'p-6 shadow-lg duration-200',
+	  'bg-background p-6 text-foreground shadow-2xl',
+	  'duration-200',
 	  'data-[state=open]:animate-in data-[state=closed]:animate-out',
 	  'data-[state=closed]:fade-out-0 data-[state=open]:fade-in-0',
 	  'data-[state=closed]:zoom-out-95 data-[state=open]:zoom-in-95',
-	  'data-[state=closed]:slide-out-to-left-1/2',
-	  'data-[state=closed]:slide-out-to-top-[48%]',
-	  'data-[state=open]:slide-in-from-left-1/2',
-	  'data-[state=open]:slide-in-from-top-[48%] rounded-lg',
 	  className)}
       {...props}
     >
       {children}
-      <DialogPrimitive.Close className="absolute right-4 top-4 bg-red-500 rounded-sm opacity-70 ring-offset-background transition-opacity hover:opacity-100 focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-2 disabled:pointer-events-none data-[state=open]:bg-accent data-[state=open]:text-muted-foreground">
+      <DialogPrimitive.Close
-        <X className="h-3 w-3" />
+	  className={cn (
-        <span className="sr-only">Close</span>
+	      'absolute right-4 top-4 rounded-full p-1',
+	      'text-muted-foreground opacity-70 transition-opacity',
+	      'hover:bg-accent hover:text-accent-foreground hover:opacity-100',
+	      'focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-2')}>
+	<X className="h-4 w-4"/>
+	<span className="sr-only">Close</span>
       </DialogPrimitive.Close>
     </DialogPrimitive.Content>
   </DialogPortal>

frontend/src/index.css

@@ -6,6 +6,56 @@
 
 @layer base
 {
+  :root
+  {
+    --background: 0 0% 100%;
+    --foreground: 222.2 84% 4.9%;
+
+    --primary: 222.2 47.4% 11.2%;
+    --primary-foreground: 210 40% 98%;
+
+    --secondary: 210 40% 96.1%;
+    --secondary-foreground: 222.2 47.4% 11.2%;
+
+    --destructive: 0 72.2% 50.6%;
+    --destructive-foreground: 210 40% 98%;
+
+    --muted: 210 40% 96.1%;
+    --muted-foreground: 215.4 16.3% 46.9%;
+
+    --accent: 210 40% 96.1%;
+    --accent-foreground: 222.2 47.4% 11.2%;
+
+    --border: 214.3 31.8% 91.4%;
+    --input: 214.3 31.8% 91.4%;
+    --ring: 222.2 84% 4.9%;
+  }
+
+  .dark
+  {
+    --background: 222.2 84% 4.9%;
+    --foreground: 210 40% 98%;
+
+    --primary: 210 40% 98%;
+    --primary-foreground: 222.2 47.4% 11.2%;
+
+    --secondary: 217.2 32.6% 17.5%;
+    --secondary-foreground: 210 40% 98%;
+
+    --destructive: 0 62.8% 45%;
+    --destructive-foreground: 210 40% 98%;
+
+    --muted: 217.2 32.6% 17.5%;
+    --muted-foreground: 215 20.2% 65.1%;
+
+    --accent: 217.2 32.6% 17.5%;
+    --accent-foreground: 210 40% 98%;
+
+    --border: 217.2 32.6% 17.5%;
+    --input: 217.2 32.6% 17.5%;
+    --ring: 212.7 26.8% 83.9%;
+  }
+
   body
   {
     @apply overflow-x-clip;
@@ -54,34 +104,6 @@ body
   min-height: 100dvh;
 }
 
-h1
-{
-  font-size: 3.2em;
-  line-height: 1.1;
-}
-
-button
-{
-  border-radius: 8px;
-  border: 1px solid transparent;
-  padding: 0.6em 1.2em;
-  font-size: 1em;
-  font-weight: 500;
-  font-family: inherit;
-  background-color: #1a1a1a;
-  cursor: pointer;
-  transition: border-color 0.25s;
-}
-button:hover
-{
-  border-color: #646cff;
-}
-button:focus,
-button:focus-visible
-{
-  outline: 4px auto -webkit-focus-ring-color;
-}
-
 @media (prefers-color-scheme: light)
 {
   :root

frontend/tailwind.config.js

@@ -19,7 +19,22 @@ export default {
 		'rainbow-scroll': 'rainbow-scroll .25s linear infinite' },
 	    colors: {
 		red: { 925: '#5f1414',
-		       975: '#230505' } },
+		       975: '#230505' },
+		border: 'hsl(var(--border))',
+		input: 'hsl(var(--input))',
+		ring: 'hsl(var(--ring))',
+		background: 'hsl(var(--background))',
+		foreground: 'hsl(var(--foreground))',
+		primary: { DEFAULT: 'hsl(var(--primary))',
+			   foreground: 'hsl(var(--primary-foreground))' },
+		secondary: { DEFAULT: 'hsl(var(--secondary))',
+			     foreground: 'hsl(var(--secondary-foreground))' },
+		destructive: { DEFAULT: 'hsl(var(--destructive))',
+			       foreground: 'hsl(var(--destructive-foreground))' },
+		muted: { DEFAULT: 'hsl(var(--muted))',
+			 foreground: 'hsl(var(--muted-foreground))' },
+		accent: { DEFAULT: 'hsl(var(--accent))',
+			  foreground: 'hsl(var(--accent-foreground))' } },
 	    keyframes: {
 		'rainbow-scroll': {
 		    '0%':   { backgroundPosition: '0% 50%' },