feat(web): add i18n, light/dark theme switching, and version constant

- Add i18n (English + 简体中文) with a locale store, $t() magic, and a language toggle (persisted)
- Add light/dark/system theme switching via a theme store and [data-theme] token overrides
- Set the theme before paint to avoid a flash of the wrong theme
- Add frontend version constant web/version.js (window.YDROPBX_VERSION) shown in the app footer
- Update AGENTS.md version-control convention to mention web/version.js
- Bump version to 0.1.1 across frontend, webui changelog, and backend constant

AGENTS.md

@@ -5,4 +5,4 @@
 - Before `git commit`: run `git branch --show-current`. If on `master`, do NOT commit — ask user for a branch name (suggest one based on the changes, e.g. `docs/simplify-branch-workflow`), create it, commit there.
 - General changes → `docs/CHANGELOG.md`; WebUI changes → `docs/CHANGELOG_webui.md` (files under `web/`). Higher versions on top.
 ANGELOG entry format: same entry has English line then Chinese line on consecutive lines (no blank line between them); different entries are separated by a blank line.
-- Version control: When bumping a version, update both the changelog and the corresponding version constant: `pkg/constant/version.go` for backend.
+- Version control: When bumping a version, update both the changelog and the corresponding version constant: `pkg/constant/version.go` for backend(docs/CHANGELOG.md), `web/version.js` for webui(docs/CHANGELOG_webui.md).

docs/CHANGELOG_webui.md

@@ -6,6 +6,22 @@ All notable changes to this template should be documented in this file.
 The format loosely follows Keep a Changelog and can be adapted to the team's habits.
 本文档参考了 Keep a Changelog 的思路，也可以根据团队习惯调整。
 
+## [0.1.1] - 2026-08-27
+
+### Added / 新增
+
+- Added internationalization (i18n): English + 简体中文, with a `locale` store, a `$t()` magic, and a language toggle persisted to localStorage.
+- 新增国际化（i18n）：支持 English 与简体中文，包含 `locale` store、`$t()` 魔法函数，以及持久化到 localStorage 的语言切换按钮。
+
+- Added light/dark/system theme switching via a `theme` store that writes `data-theme` on `<html>`; respects OS preference by default and persists the choice.
+- 新增浅色/深色/跟随系统主题切换：通过 `theme` store 在 `<html>` 上写入 `data-theme`，默认跟随系统并持久化用户选择。
+
+- Added dark-theme token overrides and a no-flash inline bootstrap script on both pages.
+- 为深色模式补充了设计令牌覆盖，并在两个页面加入防止主题闪烁的内联初始化脚本。
+
+- Added a frontend version constant (`web/version.js`, exposed as `window.YDROPBX_VERSION`) shown in the app footer, kept in sync with this changelog.
+- 新增前端版本常量（`web/version.js`，暴露为 `window.YDROPBX_VERSION`）并显示在应用页脚，与本文档版本保持一致。
+
 ## [0.1.0] - 2026-08-27
 
 ### Changed / 变更

internal/server/server.go

@@ -72,6 +72,7 @@ func (s *Server) Handler() http.Handler {
 	static := http.FileServerFS(web.FS)
 	mux.Handle("GET /components/", static)
 	mux.Handle("GET /styles/", static)
+	mux.Handle("GET /version.js", static)
 	mux.Handle("GET /alpine.min.js", static)
 
 	return mux

web/components/fileSection.js

@@ -22,7 +22,7 @@
         return this.files.length;
       },
       get title() {
-        return dir === 'inbox' ? 'Inbox' : 'Outbox';
+        return Alpine.store('locale').t(dir === 'inbox' ? 'inbox' : 'outbox');
       },
       get icon() {
         return dir === 'inbox' ? window.Icons.inbox : window.Icons.outbox;

web/components/i18n.js

@@ -0,0 +1,120 @@
+/**
+ * Internationalization (i18n).
+ *
+ * - `window.I18n` holds the message catalogs (currently English + 简体中文).
+ * - The `locale` store owns the active language, persists it to localStorage,
+ *   and exposes `t(key)`.
+ * - `$t('key')` is registered as an Alpine magic so templates can translate
+ *   inline (e.g. `x-text="$t('nav.logout')"`).
+ *
+ * Because `t()` reads the reactive `lang`, any string bound through it updates
+ * automatically when the language changes.
+ */
+window.I18n = {
+  en: {
+    'app.name': 'yDropbox',
+    'nav.logout': 'Logout',
+    'inbox': 'Inbox',
+    'outbox': 'Outbox',
+    'dropzone.click': 'Click to upload',
+    'dropzone.rest': 'or drag and drop',
+    'empty.inbox': 'No files in inbox',
+    'empty.outbox': 'No files in outbox',
+    'action.download': 'Download',
+    'action.share': 'Share',
+    'action.delete': 'Delete',
+    'toast.uploaded': 'File uploaded',
+    'toast.deleted': 'File deleted',
+    'toast.loadFailed': 'Failed to load files',
+    'toast.shareCopied': 'Share link copied to clipboard',
+    'confirm.deleteTitle': 'Delete file',
+    'confirm.deleteMessage': 'This file will be permanently removed. Continue?',
+    'confirm.cancel': 'Cancel',
+    'confirm.delete': 'Delete',
+    'confirm.confirm': 'Confirm',
+    'theme.light': 'Light',
+    'theme.dark': 'Dark',
+    'theme.system': 'System',
+    'lang.label': 'Language',
+    'login.subtitle': 'Enter your access token to continue',
+    'login.token': 'Access Token',
+    'login.submit': 'Sign In',
+    'login.error': 'Invalid token. Please try again.',
+  },
+  zh: {
+    'app.name': 'yDropbox',
+    'nav.logout': '退出登录',
+    'inbox': '收件箱',
+    'outbox': '发件箱',
+    'dropzone.click': '点击上传',
+    'dropzone.rest': '或拖拽文件到此处',
+    'empty.inbox': '收件箱暂无文件',
+    'empty.outbox': '发件箱暂无文件',
+    'action.download': '下载',
+    'action.share': '分享',
+    'action.delete': '删除',
+    'toast.uploaded': '文件已上传',
+    'toast.deleted': '文件已删除',
+    'toast.loadFailed': '文件加载失败',
+    'toast.shareCopied': '分享链接已复制到剪贴板',
+    'confirm.deleteTitle': '删除文件',
+    'confirm.deleteMessage': '该文件将被永久删除，是否继续？',
+    'confirm.cancel': '取消',
+    'confirm.delete': '删除',
+    'confirm.confirm': '确认',
+    'theme.light': '浅色',
+    'theme.dark': '深色',
+    'theme.system': '跟随系统',
+    'lang.label': '语言',
+    'login.subtitle': '请输入访问令牌以继续',
+    'login.token': '访问令牌',
+    'login.submit': '登录',
+    'login.error': '令牌无效，请重试。',
+  },
+};
+
+(function () {
+  function register() {
+    Alpine.store('locale', {
+      lang: 'en',
+
+      init() {
+        let saved = null;
+        try {
+          saved = localStorage.getItem('yd.locale');
+        } catch (e) {}
+        const browser = (navigator.language || 'en').toLowerCase().startsWith('zh') ? 'zh' : 'en';
+        this.lang = saved || browser;
+        this._applyLangAttr();
+      },
+
+      set(lang) {
+        this.lang = lang;
+        try {
+          localStorage.setItem('yd.locale', lang);
+        } catch (e) {}
+        this._applyLangAttr();
+      },
+
+      toggle() {
+        this.set(this.lang === 'en' ? 'zh' : 'en');
+      },
+
+      t(key) {
+        const dict = window.I18n[this.lang] || window.I18n.en;
+        if (dict && dict[key] != null) return dict[key];
+        if (window.I18n.en[key] != null) return window.I18n.en[key];
+        return key;
+      },
+
+      _applyLangAttr() {
+        document.documentElement.setAttribute('lang', this.lang === 'zh' ? 'zh-CN' : 'en');
+      },
+    });
+
+    Alpine.magic('t', () => (key) => Alpine.store('locale').t(key));
+  }
+
+  if (window.Alpine) register();
+  else document.addEventListener('alpine:init', register);
+})();

web/components/icons.js

@@ -30,4 +30,16 @@ window.Icons = {
 
   empty:
     '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><path d="M22 12h-4l-3 3-4-3H2"/><path d="M5.45 5.11 2 12v6a2 2 0 0 0 2 2h16a2 2 0 0 0 2-2v-6l-3.45-6.89A2 2 0 0 0 16.76 4H7.24a2 2 0 0 0-1.79 1.11z"/></svg>',
+
+  /* Theme */
+  sun:
+    '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="4"/><path d="M12 2v2M12 20v2M4.93 4.93l1.41 1.41M17.66 17.66l1.41 1.41M2 12h2M20 12h2M6.34 17.66l-1.41 1.41M19.07 4.93l-1.41 1.41"/></svg>',
+  moon:
+    '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><path d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z"/></svg>',
+  monitor:
+    '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><rect x="2" y="3" width="20" height="14" rx="2"/><line x1="8" y1="21" x2="16" y2="21"/><line x1="12" y1="17" x2="12" y2="21"/></svg>',
+
+  /* Language */
+  globe:
+    '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="10"/><line x1="2" y1="12" x2="22" y2="12"/><path d="M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z"/></svg>',
 };

web/components/store.js

@@ -24,12 +24,12 @@
           this.files.inbox = inbox.files || [];
           this.files.outbox = outbox.files || [];
         } catch (e) {
-          this.showToast('Failed to load files');
+          this.showToast('toast.loadFailed');
         }
       },
 
       showToast(message) {
-        this.toast.message = message;
+        this.toast.message = Alpine.store('locale').t(message);
         this.toast.show = true;
         if (this.toast._timer) clearTimeout(this.toast._timer);
         this.toast._timer = setTimeout(() => {
@@ -45,7 +45,7 @@
           form.append('dir', dir);
           await fetch('/api/upload', { method: 'POST', body: form });
         }
-        this.showToast('File uploaded');
+        this.showToast('toast.uploaded');
         await this.loadFiles();
       },
 
@@ -55,13 +55,13 @@
 
       async deleteFile(id) {
         const confirmed = await Alpine.store('confirm').show({
-          title: 'Delete file',
-          message: 'This file will be permanently removed. Continue?',
+          title: 'confirm.deleteTitle',
+          message: 'confirm.deleteMessage',
           danger: true,
         });
         if (!confirmed) return;
         await fetch('/api/files/' + id, { method: 'DELETE' });
-        this.showToast('File deleted');
+        this.showToast('toast.deleted');
         await this.loadFiles();
       },
 
@@ -70,7 +70,7 @@
         const data = await res.json();
         try {
           await navigator.clipboard.writeText(data.url);
-          this.showToast('Share link copied to clipboard');
+          this.showToast('toast.shareCopied');
         } catch (_) {
           window.prompt('Share URL:', data.url);
         }

web/components/theme.js

@@ -0,0 +1,64 @@
+/**
+ * Theme manager.
+ *
+ * Supports `light` / `dark` / `system`. The resolved theme is written to the
+ * `data-theme` attribute on <html>, which the CSS token layer keys off of.
+ * The `system` mode tracks the OS preference live. The choice is persisted to
+ * localStorage. A tiny inline script in each page sets the initial attribute
+ * before paint to avoid a flash of the wrong theme.
+ */
+(function () {
+  function register() {
+    Alpine.store('theme', {
+      mode: 'system', // 'light' | 'dark' | 'system'
+      resolved: 'light',
+
+      init() {
+        let saved = null;
+        try {
+          saved = localStorage.getItem('yd.theme');
+        } catch (e) {}
+        if (saved === 'light' || saved === 'dark' || saved === 'system') {
+          this.mode = saved;
+        }
+        this.apply();
+
+        const mq = window.matchMedia('(prefers-color-scheme: dark)');
+        const onChange = () => {
+          if (this.mode === 'system') this.apply();
+        };
+        if (mq.addEventListener) mq.addEventListener('change', onChange);
+        else if (mq.addListener) mq.addListener(onChange);
+      },
+
+      set(mode) {
+        this.mode = mode;
+        try {
+          localStorage.setItem('yd.theme', mode);
+        } catch (e) {}
+        this.apply();
+      },
+
+      cycle() {
+        const order = ['light', 'dark', 'system'];
+        const next = order[(order.indexOf(this.mode) + 1) % order.length];
+        this.set(next);
+      },
+
+      icon() {
+        if (this.mode === 'system') return 'monitor';
+        return this.mode === 'dark' ? 'moon' : 'sun';
+      },
+
+      apply() {
+        const mq = window.matchMedia('(prefers-color-scheme: dark)');
+        const resolved = this.mode === 'system' ? (mq.matches ? 'dark' : 'light') : this.mode;
+        this.resolved = resolved;
+        document.documentElement.setAttribute('data-theme', resolved);
+      },
+    });
+  }
+
+  if (window.Alpine) register();
+  else document.addEventListener('alpine:init', register);
+})();

web/index.html

@@ -8,8 +8,22 @@
   <link rel="stylesheet" href="/styles/base.css">
   <link rel="stylesheet" href="/styles/components.css">
 
+  <!-- Set the theme before paint to avoid a flash of the wrong theme. -->
+  <script>
+    (function () {
+      try {
+        var t = localStorage.getItem('yd.theme') || 'system';
+        var dark = t === 'dark' || (t === 'system' && window.matchMedia('(prefers-color-scheme: dark)').matches);
+        document.documentElement.setAttribute('data-theme', dark ? 'dark' : 'light');
+      } catch (e) {}
+    })();
+  </script>
+
   <!-- Components register themselves on `alpine:init`; Alpine is loaded last. -->
   <script defer src="/components/icons.js"></script>
+  <script defer src="/version.js"></script>
+  <script defer src="/components/i18n.js"></script>
+  <script defer src="/components/theme.js"></script>
   <script defer src="/components/store.js"></script>
   <script defer src="/components/fileSection.js"></script>
   <script defer src="/components/confirm.js"></script>
@@ -19,10 +33,22 @@
   <div class="app">
     <header class="app-header">
       <h1 class="brand">y<span>Dropbox</span></h1>
+      <div class="header-actions">
+        <button class="btn btn-icon" type="button"
+                @click="$store.locale.toggle()"
+                :title="$t('lang.label')" :aria-label="$t('lang.label')">
+          <span class="icon" x-html="Icons.globe"></span>
+        </button>
+        <button class="btn btn-icon" type="button"
+                @click="$store.theme.cycle()"
+                :title="$t('theme.' + $store.theme.mode)" :aria-label="$t('theme.' + $store.theme.mode)">
+          <span class="icon" x-html="Icons[$store.theme.icon()]"></span>
+        </button>
         <button class="btn btn-ghost btn-logout" @click="$store.files.logout()">
           <span class="icon" x-html="Icons.logout"></span>
-        Logout
+          <span x-text="$t('nav.logout')"></span>
         </button>
+      </div>
     </header>
 
     <main>
@@ -43,13 +69,13 @@
              @drop.prevent="dragover = false; onDrop($event)">
           <input type="file" class="drop-zone-input" @change="onSelect($event)" multiple>
           <div class="drop-zone-icon"><span class="icon" x-html="Icons.upload"></span></div>
-          <div class="drop-zone-text"><strong>Click to upload</strong> or drag and drop</div>
+          <div class="drop-zone-text"><strong x-text="$t('dropzone.click')"></strong> <span x-text="$t('dropzone.rest')"></span></div>
         </div>
 
         <template x-if="count === 0">
           <div class="empty-state">
             <span class="empty-state-icon" x-html="Icons.empty"></span>
-            <div class="empty-state-text" x-text="'No files in ' + title.toLowerCase()"></div>
+            <div class="empty-state-text" x-text="$t('empty.' + dir)"></div>
           </div>
         </template>
 
@@ -61,13 +87,13 @@
                 <div class="file-name" x-text="file.name"></div>
               </div>
               <div class="file-actions">
-                <button class="btn btn-icon" @click="$store.files.download(file.id)" title="Download">
+                <button class="btn btn-icon" @click="$store.files.download(file.id)" :title="$t('action.download')">
                   <span class="icon" x-html="Icons.download"></span>
                 </button>
-                <button class="btn btn-icon" x-show="canShare" @click="$store.files.share(file.id)" title="Share">
+                <button class="btn btn-icon" x-show="canShare" @click="$store.files.share(file.id)" :title="$t('action.share')">
                   <span class="icon" x-html="Icons.share"></span>
                 </button>
-                <button class="btn btn-icon btn-danger" @click="$store.files.deleteFile(file.id)" title="Delete">
+                <button class="btn btn-icon btn-danger" @click="$store.files.deleteFile(file.id)" :title="$t('action.delete')">
                   <span class="icon" x-html="Icons.trash"></span>
                 </button>
               </div>
@@ -93,13 +119,13 @@
              @drop.prevent="dragover = false; onDrop($event)">
           <input type="file" class="drop-zone-input" @change="onSelect($event)" multiple>
           <div class="drop-zone-icon"><span class="icon" x-html="Icons.upload"></span></div>
-          <div class="drop-zone-text"><strong>Click to upload</strong> or drag and drop</div>
+          <div class="drop-zone-text"><strong x-text="$t('dropzone.click')"></strong> <span x-text="$t('dropzone.rest')"></span></div>
         </div>
 
         <template x-if="count === 0">
           <div class="empty-state">
             <span class="empty-state-icon" x-html="Icons.empty"></span>
-            <div class="empty-state-text" x-text="'No files in ' + title.toLowerCase()"></div>
+            <div class="empty-state-text" x-text="$t('empty.' + dir)"></div>
           </div>
         </template>
 
@@ -111,10 +137,10 @@
                 <div class="file-name" x-text="file.name"></div>
               </div>
               <div class="file-actions">
-                <button class="btn btn-icon" @click="$store.files.download(file.id)" title="Download">
+                <button class="btn btn-icon" @click="$store.files.download(file.id)" :title="$t('action.download')">
                   <span class="icon" x-html="Icons.download"></span>
                 </button>
-                <button class="btn btn-icon btn-danger" @click="$store.files.deleteFile(file.id)" title="Delete">
+                <button class="btn btn-icon btn-danger" @click="$store.files.deleteFile(file.id)" :title="$t('action.delete')">
                   <span class="icon" x-html="Icons.trash"></span>
                 </button>
               </div>
@@ -141,20 +167,25 @@
            @click.stop
            role="dialog"
            aria-modal="true"
-           :aria-label="title">
-        <h3 class="modal-title" x-text="title"></h3>
-        <p class="modal-body" x-text="message"></p>
+           :aria-label="$t(title)">
+        <h3 class="modal-title" x-text="$t(title)"></h3>
+        <p class="modal-body" x-text="$t(message)"></p>
         <div class="modal-actions">
-          <button class="btn btn-ghost" type="button" @click="cancel()">Cancel</button>
+          <button class="btn btn-ghost" type="button" @click="cancel()" x-text="$t('confirm.cancel')"></button>
           <button class="btn"
                   :class="danger ? 'btn-danger' : 'btn-primary'"
                   type="button"
                   x-ref="accept"
                   @click="accept()"
-                  x-text="danger ? 'Delete' : 'Confirm'"></button>
+                  x-text="$t(danger ? 'confirm.delete' : 'confirm.confirm')"></button>
         </div>
       </div>
     </div>
+
+    <footer class="app-footer">
+      <span class="app-footer-brand">yDropbox</span>
+      <span class="app-footer-version" x-text="'v' + YDROPBX_VERSION"></span>
+    </footer>
   </div>
 </body>
 </html>

web/login.html

@@ -7,16 +7,44 @@
     <link rel="stylesheet" href="/styles/tokens.css">
     <link rel="stylesheet" href="/styles/base.css">
     <link rel="stylesheet" href="/styles/components.css">
+
+    <script>
+      (function () {
+        try {
+          var t = localStorage.getItem('yd.theme') || 'system';
+          var dark = t === 'dark' || (t === 'system' && window.matchMedia('(prefers-color-scheme: dark)').matches);
+          document.documentElement.setAttribute('data-theme', dark ? 'dark' : 'light');
+        } catch (e) {}
+      })();
+    </script>
+
+    <script defer src="/components/icons.js"></script>
+    <script defer src="/components/i18n.js"></script>
+    <script defer src="/components/theme.js"></script>
+    <script defer src="/alpine.min.js"></script>
 </head>
-<body>
+<body x-data>
+    <div class="page-topbar">
+        <button class="btn btn-icon" type="button"
+                @click="$store.locale.toggle()"
+                :title="$t('lang.label')" :aria-label="$t('lang.label')">
+            <span class="icon" x-html="Icons.globe"></span>
+        </button>
+        <button class="btn btn-icon" type="button"
+                @click="$store.theme.cycle()"
+                :title="$t('theme.' + $store.theme.mode)" :aria-label="$t('theme.' + $store.theme.mode)">
+            <span class="icon" x-html="Icons[$store.theme.icon()]"></span>
+        </button>
+    </div>
+
     <div class="login-wrap">
         <div class="login-card">
             <h1>y<span>Dropbox</span></h1>
-            <p>Enter your access token to continue</p>
+            <p x-text="$t('login.subtitle')"></p>
             <form id="loginForm">
-                <input type="password" id="token" placeholder="Access Token" required autocomplete="current-password">
-                <div class="login-error" id="loginError">Invalid token. Please try again.</div>
-                <button type="submit" class="btn btn-primary">Sign In</button>
+                <input type="password" id="token" :placeholder="$t('login.token')" required autocomplete="current-password">
+                <div class="login-error" id="loginError" x-text="$t('login.error')"></div>
+                <button type="submit" class="btn btn-primary" x-text="$t('login.submit')"></button>
             </form>
         </div>
     </div>

web/styles/components.css

@@ -23,6 +23,12 @@
   margin-bottom: var(--space-8);
 }
 
+.header-actions {
+  display: flex;
+  align-items: center;
+  gap: var(--space-2);
+}
+
 .brand {
   font-size: var(--text-2xl);
   font-weight: 700;
@@ -209,7 +215,7 @@
   align-items: center;
   gap: var(--space-3);
   padding: var(--space-3) var(--space-5);
-  border-bottom: 1px solid #f3f4f6;
+  border-bottom: 1px solid var(--color-divider);
   transition: background var(--transition-fast);
 }
 .file-row:last-child {
@@ -284,8 +290,8 @@
   padding: var(--space-3) var(--space-5);
   font-size: var(--text-sm);
   font-weight: 500;
-  color: #fff;
-  background: var(--color-text);
+  color: var(--color-toast-fg);
+  background: var(--color-toast-bg);
   border-radius: var(--radius-md);
   box-shadow: var(--shadow-lg);
   opacity: 0;
@@ -304,6 +310,24 @@
   }
 }
 
+/* ----- App footer (version) ----- */
+.app-footer {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  gap: var(--space-2);
+  margin-top: var(--space-8);
+  font-size: var(--text-xs);
+  color: var(--color-text-tertiary);
+}
+.app-footer-version {
+  font-variant-numeric: tabular-nums;
+  padding: 2px 8px;
+  background: var(--color-surface);
+  border: 1px solid var(--color-border);
+  border-radius: var(--radius-full);
+}
+
 /* ----- Modal (confirmation dialog) ----- */
 .modal-overlay {
   position: fixed;
@@ -346,6 +370,15 @@
 }
 
 /* ----- Login ----- */
+.page-topbar {
+  position: fixed;
+  top: var(--space-4);
+  right: var(--space-4);
+  display: flex;
+  gap: var(--space-2);
+  z-index: var(--z-toast);
+}
+
 .login-wrap {
   display: flex;
   align-items: center;

web/styles/tokens.css

@@ -21,6 +21,13 @@
 
   --color-success: #10b981;
 
+  /* Structural tokens */
+  --color-divider: #f3f4f6;
+  --color-toast-bg: #1a1d23;
+  --color-toast-fg: #ffffff;
+
+  color-scheme: light;
+
   /* ===== Spacing (4px base) ===== */
   --space-1: 0.25rem;
   --space-2: 0.5rem;
@@ -61,3 +68,31 @@
   --z-toast: 1000;
   --z-modal: 1100;
 }
+
+/* ===== Dark theme ===== */
+[data-theme="dark"] {
+  --color-bg: #0f1115;
+  --color-bg-gradient: radial-gradient(1200px 600px at 50% -10%, #1a2030 0%, var(--color-bg) 55%);
+  --color-surface: #171a21;
+  --color-surface-hover: #1e222b;
+  --color-border: #262b35;
+  --color-border-strong: #323844;
+
+  --color-text: #e6e8ec;
+  --color-text-secondary: #9aa1ad;
+  --color-text-tertiary: #6b7280;
+
+  --color-primary: #3b82f6;
+  --color-primary-hover: #2f6fe0;
+  --color-primary-soft: #16233f;
+
+  --color-danger: #f87171;
+  --color-danger-hover: #ef4444;
+  --color-danger-soft: #2a1717;
+
+  --color-divider: #23262f;
+  --color-toast-bg: #e6e8ec;
+  --color-toast-fg: #1a1d23;
+
+  color-scheme: dark;
+}

web/version.js

@@ -0,0 +1,3 @@
+// Frontend version. Bump this together with the top entry in
+// docs/CHANGELOG_webui.md whenever the UI changes.
+window.YDROPBX_VERSION = '0.1.1';

web/web.go

@@ -2,5 +2,5 @@ package web
 
 import "embed"
 
-//go:embed login.html index.html alpine.min.js components styles
+//go:embed login.html index.html alpine.min.js version.js components styles
 var FS embed.FS