diff --git a/app/static/css/app.css b/app/static/css/app.css
index a08de56..42563b0 100644
--- a/app/static/css/app.css
+++ b/app/static/css/app.css
@@ -313,7 +313,8 @@ ul {
 /* ── App layout (vault) ──────────────────────────────────────────── */
 .vault-page {
   height: 100vh;
-  height: 100dvh;
+  height: -webkit-fill-available;
+  height: calc(var(--vh, 1vh) * 100);
   overflow: hidden;
 }
 
@@ -850,7 +851,7 @@ ul {
   width: 100%;
   max-width: 480px;
   max-height: 90vh;
-  max-height: 90dvh;
+  max-height: calc(var(--vh, 1vh) * 90);
   overflow-y: auto;
   -webkit-overflow-scrolling: touch;
   padding: 28px;
@@ -1457,8 +1458,8 @@ ul {
 @media (max-width: 768px) {
   .app-layout {
     flex-direction: column;
-    height: 100%;
-    min-height: 100dvh;
+    height: calc(var(--vh, 1vh) * 100);
+    min-height: calc(var(--vh, 1vh) * 100);
     overflow: hidden;
   }
 
@@ -1474,8 +1475,10 @@ ul {
     left: 0;
     bottom: 0;
     width: 280px !important;
+    height: 100% !important; /* Chrome needs explicit height on position:fixed */
     z-index: 90;
     overflow-y: auto;
+    -webkit-overflow-scrolling: touch;
     transition: none;
   }
   .sidebar.mobile-open {
@@ -1483,6 +1486,14 @@ ul {
     flex-direction: column;
   }
 
+  /* Cancel all collapsed-state overrides inside mobile sidebar */
+  .sidebar.collapsed {
+    display: none !important;
+  }
+  .sidebar.collapsed.mobile-open {
+    display: flex !important;
+  }
+
   /* Mobile sidebar: always show full expanded state */
   .sidebar .sidebar-label {
     opacity: 1 !important;
@@ -1570,7 +1581,7 @@ ul {
   }
   .modal {
     max-width: 100% !important;
-    max-height: 92dvh;
+    max-height: calc(var(--vh, 1vh) * 92);
     border-radius: 16px 16px 0 0;
     padding: 20px 16px;
   }
diff --git a/app/static/js/vault.js b/app/static/js/vault.js
index 56d185c..084c9da 100644
--- a/app/static/js/vault.js
+++ b/app/static/js/vault.js
@@ -2737,4 +2737,37 @@ const Vault = (() => {
   return { init };
 })();
 
+/**
+ * Cross-browser viewport height fix.
+ *
+ * Problem: Chrome on Android uses a fixed `100vh` that includes the address bar,
+ * causing overflow when the bar is visible. Safari uses a collapsing bar model.
+ * `dvh` (dynamic viewport height) fixes this but only in Chrome 108+ / Safari 15.4+.
+ *
+ * Solution: Set `--vh` = 1% of window.innerHeight (the *actual* visible height).
+ * CSS uses `calc(var(--vh, 1vh) * 100)` instead of `100vh` everywhere.
+ * On resize (Chrome address bar show/hide, orientation change) we update --vh.
+ */
+(function setViewportHeight() {
+  function update() {
+    const vh = window.innerHeight * 0.01;
+    document.documentElement.style.setProperty("--vh", `${vh}px`);
+  }
+  update();
+  // Use ResizeObserver for Chrome (fires on address bar show/hide)
+  if (window.ResizeObserver) {
+    new ResizeObserver(update).observe(document.documentElement);
+  }
+  // Fallback: listen to resize and orientationchange
+  window.addEventListener("resize", update, { passive: true });
+  window.addEventListener(
+    "orientationchange",
+    () => {
+      // Small delay: orientation change fires before innerHeight updates
+      setTimeout(update, 100);
+    },
+    { passive: true },
+  );
+})();
+
 document.addEventListener("DOMContentLoaded", Vault.init);