diff --git a/NET10/BlazorInteractiveServer/wwwroot/input.css b/NET10/BlazorInteractiveServer/wwwroot/input.css
index 63870d7..135d5ae 100644
--- a/NET10/BlazorInteractiveServer/wwwroot/input.css
+++ b/NET10/BlazorInteractiveServer/wwwroot/input.css
@@ -3,6 +3,7 @@
 @custom-variant dark (&:is(.dark *));
 
 :root {
+  color-scheme: light;
   --background: oklch(0.9900 0 0);
   --foreground: oklch(0 0 0);
   --card: oklch(1 0 0);
@@ -58,6 +59,7 @@
 }
 
 .dark {
+  color-scheme: dark;
   --background: oklch(0 0 0);
   --foreground: oklch(1 0 0);
   --card: oklch(0.1400 0 0);
diff --git a/ShellUI.Tests/ColorSchemeTests.cs b/ShellUI.Tests/ColorSchemeTests.cs
new file mode 100644
index 0000000..5a72c61
--- /dev/null
+++ b/ShellUI.Tests/ColorSchemeTests.cs
@@ -0,0 +1,42 @@
+using System.IO;
+using ShellUI.CLI.Services;
+using ShellUI.Templates;
+using Xunit;
+
+namespace ShellUI.Tests;
+
+public class ColorSchemeTests
+{
+    [Fact]
+    public void InitTheme_SetsColorSchemeForBothThemes()
+    {
+        Assert.Contains("color-scheme: light;", CssTemplates.InputCss);
+        Assert.Contains("color-scheme: dark;", CssTemplates.InputCss);
+    }
+
+    [Fact]
+    public void AppliedTheme_SetsColorSchemeForBothThemes()
+    {
+        var css = ThemeService.BuildThemeCss(new TweakcnTheme
+        {
+            Name = "t",
+            ThemeVars = new(),
+            LightVars = new() { ["background"] = "#fff" },
+            DarkVars = new() { ["background"] = "#000" },
+        });
+
+        Assert.Contains(":root {\n  color-scheme: light;", css.Replace("\r\n", "\n"));
+        Assert.Contains(".dark {\n  color-scheme: dark;", css.Replace("\r\n", "\n"));
+    }
+
+    [Fact]
+    public void PackageTheme_SetsColorSchemeForBothThemes()
+    {
+        var root = new DirectoryInfo(System.AppContext.BaseDirectory);
+        while (root != null && !File.Exists(Path.Combine(root.FullName, "ShellUI.slnx"))) root = root.Parent;
+        var css = File.ReadAllText(Path.Combine(root!.FullName, "src", "ShellUI.Components", "wwwroot", "shellui-theme.css"));
+
+        Assert.Contains("color-scheme: light;", css);
+        Assert.Contains("color-scheme: dark;", css);
+    }
+}
diff --git a/ShellUI.Tests/PackageBehaviorTests.cs b/ShellUI.Tests/PackageBehaviorTests.cs
index f1931dc..f7427d6 100644
--- a/ShellUI.Tests/PackageBehaviorTests.cs
+++ b/ShellUI.Tests/PackageBehaviorTests.cs
@@ -62,4 +62,14 @@ public void Dropdown_ClosesOnEscapeButNotOnOtherKeys()
         dropdown.Find("div.relative").KeyDown(new KeyboardEventArgs { Key = "Escape" });
         Assert.Equal(new[] { false }, changes);
     }
+
+    [Fact]
+    public void TimePicker_ShowsASetValue()
+    {
+        using var ctx = new BunitContext();
+
+        var picker = ctx.Render<TimePicker>(p => p.Add(c => c.Value, new TimeSpan(9, 5, 0)));
+
+        Assert.Contains("09:05", picker.Markup);
+    }
 }
diff --git a/ShellUI.Tests/PackageRenderTests.cs b/ShellUI.Tests/PackageRenderTests.cs
index 260d626..099c0c8 100644
--- a/ShellUI.Tests/PackageRenderTests.cs
+++ b/ShellUI.Tests/PackageRenderTests.cs
@@ -57,6 +57,78 @@ public void EveryPackageComponent_RendersWithoutParameterBindingErrors()
         Assert.True(offenders.Count == 0, "Package components that fail parameter binding:\n  " + string.Join("\n  ", offenders));
     }
 
+    // A component that renders empty but throws once it has a value fails here (the TimePicker "HH:mm" bug).
+    [Fact]
+    public void ValueBearingComponents_RenderWithASampleValue()
+    {
+        var types = typeof(Shell).Assembly.GetExportedTypes()
+            .Where(t => typeof(IComponent).IsAssignableFrom(t) && !t.IsAbstract && t.Namespace == "ShellUI.Components")
+            .Select(t => t.IsGenericTypeDefinition ? Close(t) : t)
+            .OfType<Type>()
+            .ToList();
+
+        var tried = 0;
+        var offenders = new List<string>();
+        foreach (var type in types)
+        {
+            var values = SampleValues(type);
+            if (values.Count == 0 || !Renders(type, new Dictionary<string, object>(), out _)) continue;
+
+            tried++;
+            if (!Renders(type, values, out var error))
+                offenders.Add($"{type.Name} ({string.Join(", ", values.Keys)}): {error}");
+        }
+
+        Assert.True(tried >= 10, $"Only {tried} components had a value to set; the sample types may need extending.");
+        Assert.True(offenders.Count == 0, "Package components that throw once a value is set:\n  " + string.Join("\n  ", offenders));
+    }
+
+    private static readonly System.Text.RegularExpressions.Regex ValueLike = new("Value|Date|Time|Selected");
+
+    private static Dictionary<string, object> SampleValues(Type type)
+    {
+        var values = new Dictionary<string, object>();
+        foreach (var p in type.GetProperties())
+        {
+            if (!p.IsDefined(typeof(ParameterAttribute), true) || !p.CanWrite || !ValueLike.IsMatch(p.Name)) continue;
+            var t = Nullable.GetUnderlyingType(p.PropertyType) ?? p.PropertyType;
+            object? sample =
+                t == typeof(string) ? "b" :
+                t == typeof(DateTime) ? new DateTime(2026, 3, 14) :
+                t == typeof(DateOnly) ? new DateOnly(2026, 3, 14) :
+                t == typeof(TimeSpan) ? new TimeSpan(9, 5, 0) :
+                t == typeof(TimeOnly) ? new TimeOnly(9, 5) :
+                t == typeof(int) ? 42 :
+                t == typeof(double) ? 42.5 :
+                t == typeof(decimal) ? 42.5m :
+                t == typeof(bool) ? true :
+                t == typeof(List<string>) ? new List<string> { "a", "b" } :
+                t == typeof(IEnumerable<string>) ? new List<string> { "a", "b" } :
+                null;
+            if (sample != null) values[p.Name] = sample;
+        }
+        return values;
+    }
+
+    private static bool Renders(Type type, Dictionary<string, object> parameters, out string error)
+    {
+        using var ctx = new BunitContext();
+        ctx.JSInterop.Mode = JSRuntimeMode.Loose;
+        ctx.Services.AddShellUISonner();
+        ctx.Services.AddScoped<IThemeService, ThemeService>();
+        try
+        {
+            ctx.Render<DynamicComponent>(p => p.Add(c => c.Type, type).Add(c => c.Parameters, parameters));
+            error = "";
+            return true;
+        }
+        catch (Exception ex)
+        {
+            error = Flatten(ex);
+            return false;
+        }
+    }
+
     private static Type? Close(Type definition)
     {
         foreach (var candidate in new[] { typeof(Row), typeof(string), typeof(int) })
diff --git a/ShellUI.Tests/UpdateTests.cs b/ShellUI.Tests/UpdateTests.cs
new file mode 100644
index 0000000..e898a45
--- /dev/null
+++ b/ShellUI.Tests/UpdateTests.cs
@@ -0,0 +1,87 @@
+using System.Collections.Generic;
+using System.IO;
+using ShellUI.CLI.Services;
+using ShellUI.Core.Models;
+using ShellUI.Templates;
+using Xunit;
+
+namespace ShellUI.Tests;
+
+public class UpdateDependencyTests
+{
+    [Fact]
+    public void MissingDependencies_FindsDependenciesAddedSinceInstall()
+    {
+        // A 0.3 install of tabs and breadcrumb, before tab-models and the breadcrumb parts existed.
+        var installed = new List<string> { "tabs", "tabs-list", "tabs-trigger", "tabs-content", "breadcrumb", "breadcrumb-item" };
+
+        var missing = ComponentManager.MissingDependencies(new[] { "tabs", "breadcrumb" }, installed);
+
+        Assert.Contains("tab-models", missing);
+        Assert.Contains("breadcrumb-list", missing);
+        Assert.Contains("breadcrumb-ellipsis", missing);
+        Assert.DoesNotContain("tabs-list", missing);
+        Assert.Equal(missing.Count, new HashSet<string>(missing).Count);
+    }
+
+    [Fact]
+    public void MissingDependencies_IsEmptyWhenEverythingIsInstalled()
+    {
+        var tabs = ComponentRegistry.GetMetadata("tabs")!;
+        var installed = new List<string>(tabs.Dependencies) { "tabs" };
+
+        Assert.Empty(ComponentManager.MissingDependencies(new[] { "tabs" }, installed));
+    }
+}
+
+public class UpdateLocalChangesTests
+{
+    private const string Template = "<div class=\"p-4\">@ChildContent</div>\n";
+
+    private static InstalledComponent Entry(string name, string? hash) => new() { Name = name, Version = "0.4.0", Hash = hash };
+
+    [Fact]
+    public void FileMatchingTheRecordedHash_HasNoLocalChanges()
+    {
+        var entry = Entry("button", ComponentInstaller.ContentHash(Template));
+
+        Assert.False(ComponentManager.HasLocalChanges(entry, ComponentRegistry.GetMetadata("button")!, Template, Template));
+    }
+
+    [Fact]
+    public void EditedFile_HasLocalChanges()
+    {
+        var entry = Entry("button", ComponentInstaller.ContentHash(Template));
+
+        Assert.True(ComponentManager.HasLocalChanges(entry, ComponentRegistry.GetMetadata("button")!, Template + "<!-- mine -->", Template));
+    }
+
+    [Fact]
+    public void LineEndingChangesAreNotLocalChanges()
+    {
+        var entry = Entry("button", ComponentInstaller.ContentHash(Template));
+
+        Assert.False(ComponentManager.HasLocalChanges(entry, ComponentRegistry.GetMetadata("button")!, Template.Replace("\n", "\r\n"), Template));
+    }
+
+    [Theory]
+    [InlineData("app-sidebar")]
+    [InlineData("dashboard-02")]
+    [InlineData("auth-01")]
+    public void OlderInstall_EditableBlockThatDiffersFromTheTemplate_HasLocalChanges(string name)
+    {
+        Assert.True(ComponentManager.HasLocalChanges(Entry(name, null), ComponentRegistry.GetMetadata(name)!, "edited", Template));
+    }
+
+    [Fact]
+    public void OlderInstall_EditableBlockMatchingTheTemplate_HasNoLocalChanges()
+    {
+        Assert.False(ComponentManager.HasLocalChanges(Entry("app-sidebar", null), ComponentRegistry.GetMetadata("app-sidebar")!, Template, Template));
+    }
+
+    [Fact]
+    public void OlderInstall_OrdinaryComponentIsUpdatedAsBefore()
+    {
+        Assert.False(ComponentManager.HasLocalChanges(Entry("button", null), ComponentRegistry.GetMetadata("button")!, "edited", Template));
+    }
+}
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 66b0800..5ea66e5 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -80,7 +80,7 @@ The implemented command tree is:
 | `shellui add <components...>` | Install one or more direct targets and recursively install their registry dependencies. |
 | `shellui list` | List direct targets, with installed/available filtering. |
 | `shellui remove <components...>` | Remove selected installed source files and update `shellui.json`. |
-| `shellui update [components...]` | Rewrite selected installed source files, or all installed components with `--all`. |
+| `shellui update [components...]` | Rewrite selected installed source files, or all installed components with `--all`; skips files changed since install unless `--force`, and installs new dependencies. |
 | `shellui theme init <url-or-id>` | Initialize a project and apply a fetched theme in one operation. |
 | `shellui theme apply <url-or-id>` | Apply a theme to `wwwroot/input.css` or emit a standalone override. |
 | `shellui theme update` | Re-fetch the theme recorded in `shellui.theme.lock`. |
diff --git a/docs/CLI_SYNTAX.md b/docs/CLI_SYNTAX.md
index 67a2e79..1f6e1a1 100644
--- a/docs/CLI_SYNTAX.md
+++ b/docs/CLI_SYNTAX.md
@@ -20,7 +20,7 @@ shellui init [--force] [--style <style>] [--tailwind standalone|npm] [--yes] [--
 shellui add <name...> [--force] [--replace-layout]
 shellui list [--installed|--available]
 shellui remove <name...>
-shellui update [name...] [--all]
+shellui update [name...] [--all] [--force]
 shellui theme init <url-or-id> [--force] [--style <style>] [--tailwind standalone|npm] [--yes] [--dashboard 01|02|none] [--replace-layout]
 shellui theme apply <url-or-id> [--emit-override <path>]
 shellui theme update
@@ -142,7 +142,7 @@ shellui remove button
 shellui remove button card dialog
 ```
 
-Pass names separated by spaces. `remove` has no force flag or other options, does not prompt, and does not perform reverse-dependency cleanup. If another component still references a removed file, update that usage or remove the dependent component yourself. Layout blocks such as `dashboard-01` and `dashboard-02` currently require manual removal from `Components/Layout` because remove is not yet layout-aware.
+Pass names separated by spaces. `remove` has no force flag or other options, does not prompt, and does not perform reverse-dependency cleanup. If another component still references a removed file, update that usage or remove the dependent component yourself. Layout blocks such as `dashboard-02` and `auth-01` are removed from `Components/Layout`, and `remove` lists any files that still use the layout (usually `Routes.razor`) so you can point them at another one.
 
 ## `update`
 
@@ -153,9 +153,15 @@ shellui update button
 shellui update button card
 shellui update --all
 shellui update
+shellui update card --force
 ```
 
-Names are separated by spaces. With no names, or with `--all`, every installed component is updated. `update` overwrites files directly; there is no diff, merge, confirmation, or force option. Commit or back up local changes before updating.
+Names are separated by spaces. With no names, or with `--all`, every installed component is updated.
+
+- **Your changes are kept.** `shellui.json` records a hash of each file as the CLI wrote it. If a file has changed since, `update` skips it and says so; `--force` overwrites it. Files installed by a CLI older than 0.4.0-alpha.2 have no hash, so for those `update` keeps the blocks apps are meant to edit (`app-sidebar`, `sidebar-account`, the `dashboard-*` and `auth-*` layouts) when they differ from the template, and rewrites everything else.
+- **New dependencies are installed.** When a component gained dependencies since you installed it (for example `tabs` now needs `tab-models`), `update` adds them, with their NuGet packages and `_Imports.razor` usings, the same way `add` does.
+
+`update` has no diff or merge. Commit before updating so you can review the changes.
 
 ## `theme`
 
diff --git a/docs/FAQ.md b/docs/FAQ.md
index 65e8874..af30451 100644
--- a/docs/FAQ.md
+++ b/docs/FAQ.md
@@ -91,7 +91,7 @@ There are 93 direct targets. Use the command output as the authoritative name li
 
 ### What happens when I update a component?
 
-`update` overwrites the selected source template without showing a diff, merging changes, or asking for a force flag:
+`update` rewrites the selected components from the current templates and installs any dependencies they gained:
 
 ```bash
 shellui update button
@@ -99,11 +99,11 @@ shellui update button card
 shellui update --all
 ```
 
-Running `shellui update` without names also updates all installed components. Commit or back up local changes first.
+Running `shellui update` without names also updates all installed components. Files you have changed since the CLI wrote them are skipped; add `--force` to overwrite them. There is no diff or merge, so commit first.
 
 ### What happens when I remove a component?
 
-`remove` deletes the named component files and updates `shellui.json`. It has no options and does not perform reverse-dependency cleanup. Layout blocks such as `dashboard-01` and `dashboard-02` currently require manual removal from `Components/Layout` because remove is not yet layout-aware:
+`remove` deletes the named component files and updates `shellui.json`. It has no options and does not perform reverse-dependency cleanup. Layout blocks such as `dashboard-02` are removed from `Components/Layout`, and `remove` lists the files that still use the layout (usually `Routes.razor`):
 
 ```bash
 shellui remove button
diff --git a/docs/QUICKSTART.md b/docs/QUICKSTART.md
index dcc8cb0..47da977 100644
--- a/docs/QUICKSTART.md
+++ b/docs/QUICKSTART.md
@@ -130,9 +130,9 @@ shellui update --all
 shellui remove button card
 ```
 
-`update` overwrites the selected source files directly. It has no comparison, merge, or force step. Commit or back up custom changes before running it.
+`update` rewrites the selected source files and skips any you have changed (use `--force` to overwrite those). Commit before running it.
 
-`remove` accepts component names separated by spaces and has no options. It removes the named files, but it does not perform reverse-dependency cleanup. Layout blocks such as `dashboard-01` and `dashboard-02` currently require manual removal from `Components/Layout`. Check references before removing a component that another component may use.
+`remove` accepts component names separated by spaces and has no options. It removes the named files, but it does not perform reverse-dependency cleanup. For layout blocks such as `dashboard-02`, `remove` lists the files that still use the layout. Check references before removing a component that another component may use.
 
 ## Apply a theme
 
diff --git a/src/ShellUI.CLI/Program.cs b/src/ShellUI.CLI/Program.cs
index ab9c62f..db01e98 100644
--- a/src/ShellUI.CLI/Program.cs
+++ b/src/ShellUI.CLI/Program.cs
@@ -332,17 +332,22 @@ static Command CreateUpdateCommand()
             "Update all installed components");
         command.AddOption(allOption);
 
-        command.SetHandler((components, all) =>
+        var forceOption = new Option<bool>(
+            "--force",
+            "Also overwrite components you have changed");
+        command.AddOption(forceOption);
+
+        command.SetHandler(async (components, all, force) =>
         {
             try
             {
-                ComponentManager.UpdateComponents(components, all);
+                await ComponentManager.UpdateComponents(components, all, force);
             }
             catch (Exception ex)
             {
                 AnsiConsole.MarkupLine($"[red]Error:[/] {ex.Message.Replace("[", "[[").Replace("]", "]]")}");
             }
-        }, componentsArg, allOption);
+        }, componentsArg, allOption, forceOption);
 
         return command;
     }
diff --git a/src/ShellUI.CLI/Services/ComponentInstaller.cs b/src/ShellUI.CLI/Services/ComponentInstaller.cs
index b869844..fce99de 100644
--- a/src/ShellUI.CLI/Services/ComponentInstaller.cs
+++ b/src/ShellUI.CLI/Services/ComponentInstaller.cs
@@ -203,10 +203,7 @@ private static InstallResult InstallComponentInternal(string componentName, Shel
             return InstallResult.Failed;
         }
 
-        var basePath = metadata.IsLayoutBlock
-            ? Path.Combine(Directory.GetCurrentDirectory(), config.LayoutPath ?? "Components/Layout")
-            : Path.Combine(Directory.GetCurrentDirectory(), config.ComponentsPath);
-        var componentPath = Path.GetFullPath(Path.Combine(basePath, metadata.FilePath));
+        var componentPath = InstalledFilePath(metadata, config);
         var existing = config.InstalledComponents.FirstOrDefault(c => c.Name == componentName);
 
         if (File.Exists(componentPath) && !force)
@@ -222,7 +219,7 @@ private static InstallResult InstallComponentInternal(string componentName, Shel
 
                 content = content.Replace("YourProjectNamespace", projectInfo.RootNamespace);
                 File.WriteAllText(componentPath, content);
-                RecordInstalledComponent(config, metadata, componentName, resetCustomization: true);
+                RecordInstalledComponent(config, metadata, componentName, resetCustomization: true, ContentHash(content));
                 AnsiConsole.MarkupLine($"[green]Updated '{componentName}'[/] [dim](added sidebar interop)[/]");
                 return InstallResult.Success;
             }
@@ -241,22 +238,43 @@ private static InstallResult InstallComponentInternal(string componentName, Shel
         }
 
         File.WriteAllText(componentPath, content);
-        RecordInstalledComponent(config, metadata, componentName, resetCustomization: true);
+        RecordInstalledComponent(config, metadata, componentName, resetCustomization: true, ContentHash(content));
         AnsiConsole.MarkupLine($"[green]Installed '{componentName}'[/] [dim]({metadata.FilePath})[/]");
         return InstallResult.Success;
     }
 
+    internal static string InstalledFilePath(ComponentMetadata metadata, ShellUIConfig config)
+    {
+        var basePath = metadata.IsLayoutBlock
+            ? Path.Combine(Directory.GetCurrentDirectory(), config.LayoutPath ?? "Components/Layout")
+            : Path.Combine(Directory.GetCurrentDirectory(), config.ComponentsPath);
+        return Path.GetFullPath(Path.Combine(basePath, metadata.FilePath));
+    }
+
+    // The template as install would write it into this project.
+    internal static string? RenderedContent(string componentName, string rootNamespace) =>
+        ComponentRegistry.GetComponentContent(componentName)?.Replace("YourProjectNamespace", rootNamespace);
+
+    // Line endings are normalized so a checkout that converts CRLF doesn't count as an edit.
+    public static string ContentHash(string content)
+    {
+        var bytes = System.Text.Encoding.UTF8.GetBytes(content.Replace("\r\n", "\n"));
+        return Convert.ToHexStringLower(System.Security.Cryptography.SHA256.HashData(bytes));
+    }
+
     private static void RecordInstalledComponent(
         ShellUIConfig config,
         ComponentMetadata metadata,
         string componentName,
-        bool resetCustomization)
+        bool resetCustomization,
+        string? hash = null)
     {
         var existing = config.InstalledComponents.FirstOrDefault(c => c.Name == componentName);
         if (existing != null)
         {
             existing.Version = metadata.Version;
             if (resetCustomization) existing.IsCustomized = false;
+            if (hash != null) existing.Hash = hash;
             return;
         }
 
@@ -265,7 +283,8 @@ private static void RecordInstalledComponent(
             Name = componentName,
             Version = metadata.Version,
             InstalledAt = DateTime.UtcNow,
-            IsCustomized = false
+            IsCustomized = false,
+            Hash = hash
         });
     }
 
diff --git a/src/ShellUI.CLI/Services/ComponentManager.cs b/src/ShellUI.CLI/Services/ComponentManager.cs
index cd2ac69..0ada26c 100644
--- a/src/ShellUI.CLI/Services/ComponentManager.cs
+++ b/src/ShellUI.CLI/Services/ComponentManager.cs
@@ -102,15 +102,16 @@ public static void RemoveComponents(string[] componentNames)
             return;
         }
 
-        var installed = GetInstalledComponents();
-        var componentsPath = "Components/UI";
-
-        if (!Directory.Exists(componentsPath))
+        var config = JsonSerializer.Deserialize<ShellUIConfig>(File.ReadAllText(ConfigFileName));
+        if (config == null)
         {
-            AnsiConsole.MarkupLine("[red]Error:[/] Components directory not found.");
+            AnsiConsole.MarkupLine("[red]Error:[/] Failed to read shellui.json");
             return;
         }
 
+        var installed = config.InstalledComponents.Select(c => c.Name).ToList();
+        var removed = 0;
+
         AnsiConsole.WriteLine();
         AnsiConsole.Write(new Rule("[red]Removing Components[/]").RuleStyle("red dim"));
         AnsiConsole.WriteLine();
@@ -131,9 +132,9 @@ public static void RemoveComponents(string[] componentNames)
                 continue;
             }
 
-            if (normalizedName == "sidebar-js")
+            if (normalizedName == "sidebar-js" && ComponentRegistry.GetMetadata("sidebar-provider") is { } provider)
             {
-                var providerPath = Path.Combine(componentsPath, "SidebarProvider.razor");
+                var providerPath = ComponentInstaller.InstalledFilePath(provider, config);
                 if (File.Exists(providerPath) &&
                     File.ReadAllText(providerPath).Contains("shellui-sidebar.js", StringComparison.Ordinal))
                 {
@@ -142,28 +143,49 @@ public static void RemoveComponents(string[] componentNames)
                 }
             }
 
-            var componentPath = Path.Combine(componentsPath, metadata.FilePath);
-            
+            var componentPath = ComponentInstaller.InstalledFilePath(metadata, config);
             if (File.Exists(componentPath))
             {
                 File.Delete(componentPath);
                 AnsiConsole.MarkupLine($"[green]Removed:[/] {metadata.DisplayName}");
-                
-                installed.Remove(normalizedName);
             }
             else
             {
-                AnsiConsole.MarkupLine($"[yellow]Warning:[/] File not found: {componentPath}");
+                AnsiConsole.MarkupLine($"[green]Removed:[/] {metadata.DisplayName} [dim](its file was already gone)[/]");
+            }
+            installed.Remove(normalizedName);
+            removed++;
+
+            if (metadata.IsLayoutBlock)
+            {
+                var layout = Path.GetFileNameWithoutExtension(metadata.FilePath);
+                foreach (var file in FilesReferencing(layout))
+                    AnsiConsole.MarkupLine($"[yellow]Note:[/] {Markup.Escape(file)} still uses {layout}; point it at another layout.");
             }
         }
 
         UpdateConfig(installed);
 
         AnsiConsole.WriteLine();
-        AnsiConsole.MarkupLine($"[green]Successfully removed {componentNames.Length} component(s)[/]");
+        AnsiConsole.MarkupLine(removed > 0
+            ? $"[green]Removed {removed} component(s)[/]"
+            : "[yellow]Nothing removed[/]");
     }
 
-    public static void UpdateComponents(string[] componentNames, bool updateAll)
+    // Razor files that still name a type, so a removed layout doesn't break the build unnoticed.
+    internal static IEnumerable<string> FilesReferencing(string typeName)
+    {
+        var root = Directory.GetCurrentDirectory();
+        var pattern = new System.Text.RegularExpressions.Regex($@"\b{System.Text.RegularExpressions.Regex.Escape(typeName)}\b");
+        return Directory.EnumerateFiles(root, "*.razor", SearchOption.AllDirectories)
+            .Where(f => !f.Contains($"{Path.DirectorySeparatorChar}bin{Path.DirectorySeparatorChar}") &&
+                        !f.Contains($"{Path.DirectorySeparatorChar}obj{Path.DirectorySeparatorChar}"))
+            .Where(f => pattern.IsMatch(File.ReadAllText(f)))
+            .Select(f => Path.GetRelativePath(root, f))
+            .OrderBy(f => f);
+    }
+
+    public static async Task UpdateComponents(string[] componentNames, bool updateAll, bool force = false)
     {
         if (!File.Exists(ConfigFileName))
         {
@@ -171,16 +193,19 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
             return;
         }
 
-        var installed = GetInstalledComponents();
+        var config = JsonSerializer.Deserialize<ShellUIConfig>(File.ReadAllText(ConfigFileName));
+        var installed = config?.InstalledComponents.Select(c => c.Name).ToList() ?? new List<string>();
 
-        if (installed.Count == 0)
+        if (config == null || installed.Count == 0)
         {
             AnsiConsole.MarkupLine("[yellow]No components installed yet.[/]");
             return;
         }
 
-        var toUpdate = updateAll || componentNames.Length == 0 
-            ? installed.ToArray() 
+        var rootNamespace = ProjectDetector.DetectProject().RootNamespace;
+
+        var toUpdate = updateAll || componentNames.Length == 0
+            ? installed.ToArray()
             : componentNames;
 
         AnsiConsole.WriteLine();
@@ -190,6 +215,8 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
         var updated = 0;
         var skipped = 0;
         var failed = new List<string>();
+        var updatedNames = new List<string>();
+        var customized = new List<string>();
 
         Loaders.SnakeStatus().Start("Updating components...", ctx =>
         {
@@ -212,6 +239,19 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
                     continue;
                 }
 
+                var path = ComponentInstaller.InstalledFilePath(metadata, config);
+                if (!force && File.Exists(path))
+                {
+                    var entry = config.InstalledComponents.First(c => c.Name == normalizedName);
+                    if (HasLocalChanges(entry, metadata, File.ReadAllText(path), ComponentInstaller.RenderedContent(normalizedName, rootNamespace)))
+                    {
+                        AnsiConsole.MarkupLine($"[yellow]Skipped:[/] {metadata.DisplayName} has local changes [dim](use --force to overwrite)[/]");
+                        customized.Add(normalizedName);
+                        skipped++;
+                        continue;
+                    }
+                }
+
                 if (metadata.Dependencies.Contains("shellui-js") &&
                     !ComponentInstaller.IsShellUiJsCompatible() &&
                     !ComponentInstaller.EnsureShellUiJs())
@@ -224,6 +264,7 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
                 if (ComponentInstaller.InstallComponent(normalizedName, metadata, force: true, skipConfig: false))
                 {
                     AnsiConsole.MarkupLine($"[green]Updated:[/] {metadata.DisplayName} to v{metadata.Version}");
+                    updatedNames.Add(normalizedName);
                     updated++;
                 }
                 else
@@ -233,6 +274,8 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
             }
         });
 
+        if (customized.Count > 0) MarkCustomized(customized);
+
         AnsiConsole.WriteLine();
         if (updated > 0)
             AnsiConsole.MarkupLine($"[green]Updated {updated} component(s)[/]");
@@ -240,6 +283,54 @@ public static void UpdateComponents(string[] componentNames, bool updateAll)
             AnsiConsole.MarkupLine($"[yellow]Skipped {skipped} component(s)[/]");
         if (failed.Count > 0)
             AnsiConsole.MarkupLine($"[red]Failed: {Markup.Escape(string.Join(", ", failed))}[/]");
+
+        // Templates gain dependencies between versions (breadcrumb-list, tab-models); add them like `add` does.
+        var missing = MissingDependencies(updatedNames, GetInstalledComponents());
+        if (missing.Count > 0)
+        {
+            AnsiConsole.WriteLine();
+            AnsiConsole.MarkupLine($"[blue]Installing new dependencies:[/] {string.Join(", ", missing)}");
+            await ComponentInstaller.InstallComponents(missing.ToArray(), force: false);
+        }
+    }
+
+    // Blocks apps are told to edit. Entries from before hashes were recorded can only be compared with the current template.
+    private static bool IsEditableBlock(ComponentMetadata metadata) =>
+        metadata.IsLayoutBlock || metadata.Name is "app-sidebar" or "sidebar-account";
+
+    public static bool HasLocalChanges(InstalledComponent entry, ComponentMetadata metadata, string current, string? template)
+    {
+        var hash = ComponentInstaller.ContentHash(current);
+        if (entry.Hash != null) return hash != entry.Hash;
+        return IsEditableBlock(metadata) && template != null && hash != ComponentInstaller.ContentHash(template);
+    }
+
+    public static List<string> MissingDependencies(IEnumerable<string> components, ICollection<string> installed)
+    {
+        var missing = new List<string>();
+        var seen = new HashSet<string>(installed);
+        var queue = new Queue<string>(components);
+        while (queue.Count > 0)
+        {
+            var metadata = ComponentRegistry.GetMetadata(queue.Dequeue());
+            if (metadata == null) continue;
+            foreach (var dep in metadata.Dependencies)
+            {
+                if (!seen.Add(dep)) continue;
+                missing.Add(dep);
+                queue.Enqueue(dep);
+            }
+        }
+        return missing;
+    }
+
+    private static void MarkCustomized(List<string> names)
+    {
+        var config = JsonSerializer.Deserialize<ShellUIConfig>(File.ReadAllText(ConfigFileName));
+        if (config == null) return;
+        foreach (var entry in config.InstalledComponents.Where(c => names.Contains(c.Name)))
+            entry.IsCustomized = true;
+        File.WriteAllText(ConfigFileName, JsonSerializer.Serialize(config, new JsonSerializerOptions { WriteIndented = true }));
     }
 
     private static void UpdateConfig(List<string> installedComponentNames)
diff --git a/src/ShellUI.CLI/Services/ThemeService.cs b/src/ShellUI.CLI/Services/ThemeService.cs
index 18ad88f..0a5ce80 100644
--- a/src/ShellUI.CLI/Services/ThemeService.cs
+++ b/src/ShellUI.CLI/Services/ThemeService.cs
@@ -102,8 +102,8 @@ public static string BuildThemeCss(TweakcnTheme theme)
         sb.AppendLine(BeginMarker);
         sb.AppendLine($"/* Theme: {theme.Name} — fetched from tweakcn */");
 
-        WriteBlock(sb, ":root", theme.LightVars);
-        WriteBlock(sb, ".dark", theme.DarkVars);
+        WriteBlock(sb, ":root", "light", theme.LightVars);
+        WriteBlock(sb, ".dark", "dark", theme.DarkVars);
 
         if (theme.ThemeVars.Count > 0)
         {
@@ -118,11 +118,13 @@ public static string BuildThemeCss(TweakcnTheme theme)
         return sb.ToString();
     }
 
-    private static void WriteBlock(StringBuilder sb, string selector, Dictionary<string, string> vars)
+    // color-scheme makes the browser's own controls (date popups, scrollbars, select lists) follow the theme.
+    private static void WriteBlock(StringBuilder sb, string selector, string colorScheme, Dictionary<string, string> vars)
     {
         if (vars.Count == 0) return;
         sb.AppendLine();
         sb.AppendLine($"{selector} {{");
+        sb.AppendLine($"  color-scheme: {colorScheme};");
         foreach (var (k, v) in vars.OrderBy(kv => kv.Key, StringComparer.Ordinal))
             sb.AppendLine($"  --{k}: {v};");
         sb.AppendLine("}");
diff --git a/src/ShellUI.Components/Components/TimePicker.razor b/src/ShellUI.Components/Components/TimePicker.razor
index 116facd..f0615c8 100644
--- a/src/ShellUI.Components/Components/TimePicker.razor
+++ b/src/ShellUI.Components/Components/TimePicker.razor
@@ -6,7 +6,7 @@
             disabled="@Disabled"
             class="@Shell.Cn("flex h-10 w-full items-center justify-between rounded-md border border-input bg-background px-3 py-2 text-sm ring-offset-background focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-2", Disabled ? "cursor-not-allowed opacity-50" : "")">
         <span class="@(Value == null ? "text-muted-foreground" : "")">
-            @(Value?.ToString("HH:mm") ?? Placeholder)
+            @(Value?.ToString(@"hh\:mm") ?? Placeholder)
         </span>
         <svg class="h-4 w-4 opacity-50" fill="none" viewBox="0 0 24 24" stroke="currentColor">
             <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z" />
diff --git a/src/ShellUI.Components/wwwroot/shellui-theme.css b/src/ShellUI.Components/wwwroot/shellui-theme.css
index 39a8a34..bb94e87 100644
--- a/src/ShellUI.Components/wwwroot/shellui-theme.css
+++ b/src/ShellUI.Components/wwwroot/shellui-theme.css
@@ -1,4 +1,5 @@
 :root {
+  color-scheme: light;
   --background: oklch(0.9900 0 0);
   --foreground: oklch(0 0 0);
   --card: oklch(1 0 0);
@@ -54,6 +55,7 @@
 }
 
 .dark {
+  color-scheme: dark;
   --background: oklch(0 0 0);
   --foreground: oklch(1 0 0);
   --card: oklch(0.1400 0 0);
diff --git a/src/ShellUI.Core/Models/ShellUIConfig.cs b/src/ShellUI.Core/Models/ShellUIConfig.cs
index d2186eb..10ca716 100644
--- a/src/ShellUI.Core/Models/ShellUIConfig.cs
+++ b/src/ShellUI.Core/Models/ShellUIConfig.cs
@@ -1,3 +1,4 @@
+using System.Text.Json.Serialization;
 using ShellUI.Core;
 
 namespace ShellUI.Core.Models;
@@ -28,6 +29,10 @@ public class InstalledComponent
     public required string Version { get; set; }
     public DateTime InstalledAt { get; set; } = DateTime.UtcNow;
     public bool IsCustomized { get; set; }
+
+    // SHA-256 of the file as the CLI wrote it; update compares against it to spot local edits.
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string? Hash { get; set; }
 }
 
 public enum ProjectType
diff --git a/src/ShellUI.Templates/CssTemplates.cs b/src/ShellUI.Templates/CssTemplates.cs
index 67b7e59..97a1e4c 100644
--- a/src/ShellUI.Templates/CssTemplates.cs
+++ b/src/ShellUI.Templates/CssTemplates.cs
@@ -35,6 +35,7 @@ public static class CssTemplates
 @custom-variant dark (&:is(.dark *));
 
 :root {
+  color-scheme: light;
   --background: oklch(0.9900 0 0);
   --foreground: oklch(0 0 0);
   --card: oklch(1 0 0);
@@ -90,6 +91,7 @@ public static class CssTemplates
 }
 
 .dark {
+  color-scheme: dark;
   --background: oklch(0 0 0);
   --foreground: oklch(1 0 0);
   --card: oklch(0.1400 0 0);