04/18 fix toggle button of sidebar

app/static/css/app.css

@@ -310,27 +310,39 @@ ul {
   display: flex;
   flex-direction: column;
   overflow: hidden;
-  overflow-y: auto;
   transition: width 0.22s ease;
 }
 
 .sidebar.collapsed {
   width: 56px;
-  overflow-y: visible;
+}
+
+/* Sidebar must not clip its children when collapsed — tooltips need to escape */
+.sidebar.collapsed .sidebar-nav,
+.sidebar.collapsed .sidebar-footer {
+  overflow: visible;
 }
 
 .sidebar-header {
   display: flex;
   align-items: center;
   gap: 8px;
-  padding: 18px 16px;
+  padding: 14px 12px;
   border-bottom: 1px solid rgba(255, 255, 255, 0.08);
   flex-shrink: 0;
-  min-height: 60px;
+  min-height: 56px;
+  overflow: hidden;
+}
+/* When collapsed: centre the toggle button, hide everything else */
+.sidebar.collapsed .sidebar-header {
+  justify-content: center;
+  padding: 14px 0;
+  overflow: visible;
 }
 .sidebar-header .logo-icon {
   font-size: 22px;
   flex-shrink: 0;
+  transition: opacity 0.15s ease;
 }
 .sidebar-header .logo-text {
   font-size: 16px;
@@ -339,41 +351,45 @@ ul {
   flex: 1;
   white-space: nowrap;
   overflow: hidden;
-  transition:
-    opacity 0.15s ease,
-    width 0.15s ease;
+  transition: opacity 0.15s ease;
 }
+.sidebar.collapsed .sidebar-header .logo-icon,
 .sidebar.collapsed .sidebar-header .logo-text {
   opacity: 0;
   width: 0;
+  pointer-events: none;
 }
 
-/* Toggle button */
+/* Toggle button — always visible, always clickable */
 .btn-sidebar-toggle {
   background: none;
   border: none;
   color: rgba(255, 255, 255, 0.5);
-  font-size: 13px;
+  font-size: 14px;
   cursor: pointer;
-  padding: 4px 6px;
+  padding: 6px 8px;
   border-radius: 4px;
   line-height: 1;
   flex-shrink: 0;
   transition:
     color var(--transition),
     transform 0.22s ease;
+  margin-left: auto;
+  z-index: 10;
 }
 .btn-sidebar-toggle:hover {
   color: #fff;
-  background: rgba(255, 255, 255, 0.1);
+  background: rgba(255, 255, 255, 0.12);
 }
 .sidebar.collapsed .btn-sidebar-toggle {
   transform: rotate(180deg);
+  margin-left: 0;
 }
 
 .sidebar-nav {
   flex: 1;
   padding: 8px 0;
+  overflow-y: auto;
 }
 
 .sidebar-section-header {
@@ -389,6 +405,8 @@ ul {
 .sidebar.collapsed .sidebar-section-header {
   opacity: 0;
   pointer-events: none;
+  height: 0;
+  padding: 0;
 }
 
 .sidebar-item {
@@ -405,6 +423,7 @@ ul {
   text-align: left;
   position: relative;
   white-space: nowrap;
+  overflow: hidden;
 }
 .sidebar-item:hover {
   background: var(--color-sidebar-hover);
@@ -418,29 +437,24 @@ ul {
   flex-shrink: 0;
 }
 
-/* Hide labels and show tooltip when collapsed */
+/* Labels — fade out when collapsed */
 .sidebar-label {
-  overflow: hidden;
-  transition:
-    opacity 0.15s ease,
-    width 0.15s ease;
+  transition: opacity 0.15s ease;
 }
 .sidebar.collapsed .sidebar-label {
   opacity: 0;
-  width: 0;
 }
 .sidebar.collapsed .sidebar-item {
   justify-content: center;
   padding: 9px 0;
+  overflow: visible; /* allow tooltip to escape */
 }
 
 /* Tooltip — shown on hover in collapsed state */
 .sidebar.collapsed .sidebar-item::after {
   content: attr(data-tooltip);
-  position: absolute;
-  left: calc(100% + 8px);
-  top: 50%;
-  transform: translateY(-50%);
+  position: fixed;
+  left: 64px;
   background: #111827;
   color: #fff;
   font-size: 12px;
@@ -450,7 +464,7 @@ ul {
   pointer-events: none;
   opacity: 0;
   transition: opacity 0.12s ease;
-  z-index: 200;
+  z-index: 1000;
   box-shadow: 0 2px 8px rgba(0, 0, 0, 0.35);
 }
 .sidebar.collapsed .sidebar-item:hover::after {