diff --git a/HellionChat/Ui/Settings.cs b/HellionChat/Ui/Settings.cs
index 538fc9f..cec9ea5 100755
--- a/HellionChat/Ui/Settings.cs
+++ b/HellionChat/Ui/Settings.cs
@@ -45,6 +45,7 @@ public sealed class SettingsWindow : Dalamud.Interface.Windowing.Window
         [
             new General(Plugin, Mutable),
             new Appearance(Plugin, Mutable),
+            new SettingsTabs.Themes(Plugin, Mutable),
             new SettingsTabs.Window(Plugin, Mutable),
             new Chat(Plugin, Mutable),
             new SettingsTabs.Tabs(Plugin, Mutable),
diff --git a/HellionChat/Ui/SettingsOverview.cs b/HellionChat/Ui/SettingsOverview.cs
index 0574021..9715bbe 100644
--- a/HellionChat/Ui/SettingsOverview.cs
+++ b/HellionChat/Ui/SettingsOverview.cs
@@ -12,12 +12,12 @@ internal sealed class SettingsOverview
     private readonly SettingsWindow _window;
 
     // Card-Reihenfolge entspricht 1:1 dem Tabs-Index in SettingsWindow.
-    // Themes (Phase J) wird später als Card 2 zwischen Appearance und Window
-    // eingeschoben — dabei muss diese Liste neu gemappt werden.
+    // Themes ist Card-Index 2, eingeschoben zwischen Appearance und Window.
     private static readonly (FontAwesomeIcon Icon, string TitleKey, string SubtextKey)[] CardDefs =
     [
         (FontAwesomeIcon.SlidersH,        "Settings_Card_General_Title",     "Settings_Card_General_Subtext"),
         (FontAwesomeIcon.Palette,         "Settings_Card_Appearance_Title",  "Settings_Card_Appearance_Subtext"),
+        (FontAwesomeIcon.Swatchbook,      "Settings_Card_Themes_Title",      "Settings_Card_Themes_Subtext"),
         (FontAwesomeIcon.WindowMaximize,  "Settings_Card_Window_Title",      "Settings_Card_Window_Subtext"),
         (FontAwesomeIcon.Comments,        "Settings_Card_Chat_Title",        "Settings_Card_Chat_Subtext"),
         (FontAwesomeIcon.FolderTree,      "Settings_Card_Tabs_Title",        "Settings_Card_Tabs_Subtext"),
diff --git a/HellionChat/Ui/SettingsTabs/Themes.cs b/HellionChat/Ui/SettingsTabs/Themes.cs
new file mode 100644
index 0000000..0fe85af
--- /dev/null
+++ b/HellionChat/Ui/SettingsTabs/Themes.cs
@@ -0,0 +1,147 @@
+using System.Numerics;
+using Dalamud.Bindings.ImGui;
+using Dalamud.Interface.Utility.Raii;
+using HellionChat.Resources;
+using HellionChat.Themes;
+using HellionChat.Util;
+
+namespace HellionChat.Ui.SettingsTabs;
+
+internal sealed class Themes : ISettingsTab
+{
+    private readonly Plugin Plugin;
+    private readonly Configuration Mutable;
+
+    public string Name => HellionStrings.ResourceManager.GetString("Settings_Tab_Themes") ?? "Themes" + "###tabs-themes";
+
+    internal Themes(Plugin plugin, Configuration mutable)
+    {
+        Plugin = plugin;
+        Mutable = mutable;
+    }
+
+    public void Draw(bool changed)
+    {
+        var registry = Plugin.ThemeRegistry;
+        var active = registry.Get(Mutable.Theme);
+
+        var activeLabelTemplate = HellionStrings.ResourceManager.GetString("Settings_Themes_Active") ?? "Active: {0}";
+        ImGui.TextUnformatted(string.Format(activeLabelTemplate, active.Name));
+        using (ImRaii.PushColor(ImGuiCol.Text, 0xFF8FA3B5u))
+            ImGui.TextUnformatted(active.Author);
+
+        ImGui.Spacing();
+        ImGui.Separator();
+        ImGui.Spacing();
+
+        var builtInsLabel = HellionStrings.ResourceManager.GetString("Settings_Themes_BuiltIns") ?? "Built-in themes";
+        ImGui.TextUnformatted(builtInsLabel);
+        ImGui.Spacing();
+        DrawThemeGrid(registry.AllBuiltIns(), active.Slug);
+
+        var customs = registry.AllCustom().ToList();
+        if (customs.Count > 0)
+        {
+            ImGui.Spacing();
+            ImGui.Separator();
+            ImGui.Spacing();
+            var customLabel = HellionStrings.ResourceManager.GetString("Settings_Themes_Custom") ?? "Custom themes";
+            ImGui.TextUnformatted(customLabel);
+            ImGui.Spacing();
+            DrawThemeGrid(customs, active.Slug);
+        }
+
+        ImGui.Spacing();
+        ImGui.Separator();
+        ImGui.Spacing();
+
+        var openFolderLabel = HellionStrings.ResourceManager.GetString("Settings_Themes_OpenFolder") ?? "Open themes folder";
+        if (ImGui.Button(openFolderLabel))
+        {
+            var dir = Path.Combine(Plugin.Interface.ConfigDirectory.FullName, "themes");
+            Directory.CreateDirectory(dir);
+            Dalamud.Utility.Util.OpenLink(dir);
+        }
+
+        ImGui.SameLine();
+        var exportLabel = HellionStrings.ResourceManager.GetString("Settings_Themes_ExportActive") ?? "Export active...";
+        if (ImGui.Button(exportLabel))
+        {
+            // Export-Logik wird in Phase L (Task 21) ergänzt — Stub belassen, Button bleibt sichtbar.
+        }
+    }
+
+    private void DrawThemeGrid(IEnumerable<Theme> themes, string activeSlug)
+    {
+        var avail = ImGui.GetContentRegionAvail();
+        var columns = avail.X >= 700f ? 3 : 2;
+        var cardWidth = (avail.X - (columns - 1) * 8f) / columns;
+        var cardHeight = 110f;
+        var i = 0;
+        foreach (var theme in themes)
+        {
+            DrawThemeCard(theme, activeSlug, cardWidth, cardHeight);
+            i++;
+            if (i % columns != 0)
+                ImGui.SameLine();
+            else
+                ImGui.NewLine();
+        }
+    }
+
+    private void DrawThemeCard(Theme theme, string activeSlug, float w, float h)
+    {
+        var isActive = string.Equals(theme.Slug, activeSlug, StringComparison.OrdinalIgnoreCase);
+        var cursorBefore = ImGui.GetCursorScreenPos();
+        var clicked = ImGui.InvisibleButton($"##theme-card-{theme.Slug}", new Vector2(w, h));
+        var hovered = ImGui.IsItemHovered();
+
+        var draw = ImGui.GetWindowDrawList();
+        var bg = ColourUtil.RgbaToAbgr(theme.Colors.WindowBg | 0xFFu);
+        draw.AddRectFilled(cursorBefore, cursorBefore + new Vector2(w, h), bg, 4f);
+
+        if (isActive)
+        {
+            var border = ColourUtil.RgbaToAbgr(theme.Colors.Primary);
+            draw.AddRect(cursorBefore, cursorBefore + new Vector2(w, h), border, 4f, ImDrawFlags.None, 2f);
+        }
+        else if (hovered)
+        {
+            var border = ColourUtil.RgbaToAbgr(theme.Colors.PrimaryLight & 0xFFFFFF99u);
+            draw.AddRect(cursorBefore, cursorBefore + new Vector2(w, h), border, 4f, ImDrawFlags.None, 1f);
+        }
+
+        // Akzent-Swatch links oben
+        var swatchPos = cursorBefore + new Vector2(12f, 12f);
+        var swatchSize = new Vector2(20f, 20f);
+        draw.AddRectFilled(swatchPos, swatchPos + swatchSize, ColourUtil.RgbaToAbgr(theme.Colors.Primary), 3f);
+
+        // Name
+        ImGui.SetCursorScreenPos(cursorBefore + new Vector2(40f, 12f));
+        var textColor = ColourUtil.RgbaToAbgr(theme.Colors.TextPrimary);
+        using (ImRaii.PushColor(ImGuiCol.Text, textColor))
+            ImGui.TextUnformatted(theme.Name);
+
+        // Author
+        ImGui.SetCursorScreenPos(cursorBefore + new Vector2(40f, 32f));
+        var mutedColor = ColourUtil.RgbaToAbgr(theme.Colors.TextMuted);
+        using (ImRaii.PushColor(ImGuiCol.Text, mutedColor))
+            ImGui.TextUnformatted(theme.Author);
+
+        // Description (wrapped, falls zu lang)
+        ImGui.SetCursorScreenPos(cursorBefore + new Vector2(12f, 60f));
+        ImGui.PushTextWrapPos(cursorBefore.X + w - 12f);
+        using (ImRaii.PushColor(ImGuiCol.Text, mutedColor))
+            ImGui.TextUnformatted(theme.Description);
+        ImGui.PopTextWrapPos();
+
+        // Cursor unter die Card setzen
+        ImGui.SetCursorScreenPos(cursorBefore + new Vector2(0f, h + 8f));
+
+        if (clicked)
+        {
+            Mutable.Theme = theme.Slug;
+            Plugin.ThemeRegistry.Switch(theme.Slug);
+        }
+    }
+}