v2.1.4 — 侧边栏深色主题：深蓝渐变背景+蓝色图标+浅灰文字

static/app.js

@@ -186,7 +186,7 @@
       if (w === todayWk) cls += ' today';
       if (w === selectedWeek) cls += ' selected';
       wHtml += '<div class="' + cls + '" data-week="' + w + '" title="' + w + '">' +
-        'W' + w.split('-W')[1].replace(/^0/, '') + '</div>';
+        '第' + w.split('-W')[1].replace(/^0/, '') + '周</div>';
     }
     var we = document.getElementById('cal-weeks');
     we.innerHTML = wHtml;

static/style.css

@@ -174,6 +174,45 @@ body {
   font-weight: 400;
 }
 
+/* ═══════════════════════════════════════════
+   Sidebar Dark Theme（左侧导航栏专属）
+   ═══════════════════════════════════════════ */
+.sidebar {
+  background: linear-gradient(180deg, #1E293B 0%, #0F172A 100%);
+  border-right: 1px solid #334155;
+}
+.sidebar .user-name {
+  color: #94A3B8;
+}
+.sidebar .user-avatar {
+  background: #4F46E5;
+  color: #FFF;
+}
+.sidebar .btn-logout-icon {
+  color: #64748B;
+}
+.sidebar .btn-logout-icon:hover {
+  background: rgba(248,113,113,0.15);
+  color: #FCA5A5;
+}
+.sidebar .nav-item {
+  color: #94A3B8;
+}
+.sidebar .nav-item:hover {
+  background: rgba(99,102,241,0.08);
+  color: #E2E8F0;
+}
+.sidebar .nav-item .icon-md {
+  color: #6366F1;
+}
+.sidebar .nav-item:hover .icon-md { color: #818CF8; }
+.sidebar .nav-item.active {
+  background: rgba(99,102,241,0.15);
+  color: #FFF;
+  border: 1px solid rgba(99,102,241,0.3);
+}
+.sidebar .nav-item.active .icon-md { color: #818CF8; }
+
 /* ═══════════════════════════════════════════
    Calendar Widget
    ═══════════════════════════════════════════ */
@@ -220,14 +259,13 @@ body {
 
 /* 周选择 */
 .cal-weeks {
-  display: flex;
+  display: grid;
+  grid-template-columns: repeat(2, 1fr);
   gap: 8px;
   padding: 8px 14px 10px;
-  justify-content: center;
 }
 .cal-week-cell {
-  width: 44px;
-  height: 44px;
+  height: 42px;
   display: flex;
   align-items: center;
   justify-content: center;