diff --git a/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/chrome.css b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/chrome.css
new file mode 100644
index 000000000..897b96dec
--- /dev/null
+++ b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/chrome.css
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+
+:root {
+  --simhae-base00: #0a1f2e;
+  --simhae-base01: #142c3e;
+  --simhae-base02: #1c3a50;
+  --simhae-base03: #24425c;
+  --simhae-base04: #4a6e86;
+  --simhae-base05: #c6d8e4;
+  --simhae-base06: #d6e2e8;
+  --simhae-base07: #ecf0f4;
+  --simhae-base08: #c47a72;
+  --simhae-base09: #c8945a;
+  --simhae-base0a: #c8ae6a;
+  --simhae-base0b: #68be92;
+  --simhae-base0c: #50c4c0;
+  --simhae-base0d: #7896cc;
+  --simhae-base0e: #9a7ec8;
+  --simhae-base0f: #8c6040;
+  --simhae-base10: #071420;
+  --simhae-base11: #d08880;
+  --simhae-base12: #d4a870;
+  --simhae-base13: #d4be82;
+  --simhae-base14: #80ccaa;
+  --simhae-base15: #68d4d0;
+  --simhae-base16: #90aed8;
+  --simhae-base17: #ae96d4;
+
+--simhae-front-app-foreground: var(--simhae-base05);
+  --simhae-front-app-background: var(--simhae-base01);
+  --simhae-front-app-border: rgba(74, 110, 134, 0.9);
+  --simhae-sidebar-reveal-border: rgba(74, 110, 134, 0.68);
+  --simhae-sidebar-reveal-border-muted: rgba(74, 110, 134, 0.42);
+
+--zen-primary-color: var(--simhae-sidebar-reveal-border) !important;
+  --zen-colors-primary: var(--simhae-sidebar-reveal-border) !important;
+  --zen-colors-secondary: var(--simhae-base0d) !important;
+  --zen-colors-tertiary: var(--simhae-base02) !important;
+  --zen-colors-border: var(--simhae-base03) !important;
+  --zen-colors-hover-bg: var(--simhae-base02) !important;
+  --zen-colors-toolbar: var(--simhae-base00) !important;
+  --zen-main-browser-background: var(--simhae-base00) !important;
+  --zen-themed-toolbar-bg: var(--simhae-base00) !important;
+  --toolbar-bgcolor: var(--simhae-base00) !important;
+  --toolbar-color: var(--simhae-base05) !important;
+  --lwt-accent-color: var(--simhae-base00) !important;
+  --lwt-text-color: var(--simhae-base05) !important;
+  --lwt-toolbar-field-background-color: var(--simhae-base01) !important;
+  --lwt-toolbar-field-color: var(--simhae-base05) !important;
+  --lwt-toolbar-field-border-color: var(--simhae-base03) !important;
+  --lwt-toolbar-field-focus: var(--simhae-front-app-background) !important;
+  --lwt-toolbar-field-focus-color: var(--simhae-front-app-foreground) !important;
+  --urlbarView-highlight-background: var(--simhae-base02) !important;
+  --urlbarView-highlight-color: var(--simhae-base07) !important;
+  --urlbarView-separator-color: var(--simhae-base03) !important;
+  --arrowpanel-background: var(--simhae-base01) !important;
+  --arrowpanel-color: var(--simhae-base05) !important;
+  --arrowpanel-border-color: var(--simhae-base03) !important;
+  --sidebar-background-color: var(--simhae-base00) !important;
+  --sidebar-border-color: var(--simhae-sidebar-reveal-border) !important;
+  --sidebar-text-color: var(--simhae-base05) !important;
+  --chrome-content-separator-color: var(--simhae-sidebar-reveal-border) !important;
+  --toolbar-background-color: var(--simhae-base00) !important;
+  --toolbox-background-color: var(--simhae-base00) !important;
+  --toolbox-background-color-inactive: var(--simhae-base00) !important;
+  --toolbox-text-color: var(--simhae-base05) !important;
+  --toolbox-text-color-inactive: var(--simhae-base05) !important;
+}
+
+#TabsToolbar,
+#nav-bar,
+#PersonalToolbar {
+  background-color: var(--simhae-base00) !important;
+  color: var(--simhae-base05) !important;
+  border-color: var(--simhae-base03) !important;
+}
+
+#navigator-toolbox {
+  background-color: var(--simhae-base00) !important;
+  color: var(--simhae-base05) !important;
+  border-color: var(--simhae-sidebar-reveal-border) !important;
+  box-shadow: none !important;
+}
+
+#navigator-toolbox .zen-toolbar-background {
+  background: var(--simhae-base00) !important;
+  background-color: var(--simhae-base00) !important;
+  border: 2px solid var(--simhae-sidebar-reveal-border) !important;
+  box-shadow: none !important;
+}
+
+#navigator-toolbox .zen-toolbar-background::before,
+#navigator-toolbox .zen-toolbar-background::after {
+  background: var(--simhae-base00) !important;
+  background-color: var(--simhae-base00) !important;
+  box-shadow: none !important;
+  outline: 2px solid var(--simhae-sidebar-reveal-border) !important;
+  outline-offset: -2px !important;
+}
+
+.urlbar-background,
+#searchbar {
+  background-color: var(--simhae-base01) !important;
+  border-color: var(--simhae-base03) !important;
+  color: var(--simhae-base05) !important;
+}
+
+#urlbar[focused="true"] > .urlbar-background,
+#urlbar[focused="true"] > .urlbar-input-container {
+  background: var(--simhae-front-app-background) !important;
+  border: none !important;
+  box-shadow: none !important;
+  outline: none !important;
+}
+
+#urlbar[open] > .urlbar-background,
+#urlbar[open] > .urlbar-input-container {
+  background: var(--simhae-front-app-background) !important;
+  border: none !important;
+  box-shadow: none !important;
+  outline: none !important;
+}
+
+#urlbar[breakout][breakout-extend] {
+  background: var(--simhae-front-app-background) !important;
+  color: var(--simhae-front-app-foreground) !important;
+  border: 3px solid var(--simhae-front-app-border) !important;
+  border-radius: 12px !important;
+  overflow: clip !important;
+}
+
+#urlbar[breakout][breakout-extend] > .urlbar-background,
+#urlbar[breakout][breakout-extend] > .urlbar-input-container {
+  background: var(--simhae-front-app-background) !important;
+  background-color: var(--simhae-front-app-background) !important;
+  border: none !important;
+  box-shadow: none !important;
+  outline: none !important;
+}
+
+#urlbar[breakout][breakout-extend] .urlbarView {
+  background: var(--simhae-front-app-background) !important;
+  border: none !important;
+  border-top: 1px solid var(--simhae-front-app-border) !important;
+  border-radius: 0 !important;
+  box-shadow: none !important;
+}
+
+#urlbar[breakout][breakout-extend] #urlbar-input,
+#urlbar[breakout][breakout-extend] .urlbar-input {
+  color: var(--simhae-front-app-foreground) !important;
+}
+
+.urlbarView,
+.urlbarView-body-outer,
+.urlbarView-body-inner,
+.urlbarView-results,
+.urlbarView-row-inner {
+  background: var(--simhae-front-app-background) !important;
+  color: var(--simhae-front-app-foreground) !important;
+  border: none !important;
+  border-color: transparent !important;
+}
+
+.urlbarView-row:hover,
+.urlbarView-row[selected] {
+  background-color: var(--simhae-base02) !important;
+  color: var(--simhae-front-app-foreground) !important;
+}
+
+.urlbarView-title,
+.urlbarView-url {
+  color: var(--simhae-front-app-foreground) !important;
+}
+
+.tab-background {
+  background-color: transparent !important;
+  border: 1px solid transparent !important;
+}
+
+.tabbrowser-tab:hover > .tab-stack > .tab-background {
+  background-color: var(--simhae-base02) !important;
+}
+
+.tabbrowser-tab[selected="true"] > .tab-stack > .tab-background,
+.tabbrowser-tab[multiselected="true"] > .tab-stack > .tab-background {
+  background-color: var(--simhae-base01) !important;
+  border-color: var(--simhae-base03) !important;
+}
+
+.tabbrowser-tab[selected="true"] .tab-label,
+.tabbrowser-tab[multiselected="true"] .tab-label {
+  color: var(--simhae-base07) !important;
+}
+
+.tabbrowser-tab[selected="true"] .tab-background::before {
+  background-color: var(--simhae-base0c) !important;
+}
+
+toolbarbutton,
+.toolbarbutton-1,
+.urlbar-page-action {
+  color: var(--simhae-base05) !important;
+}
+
+toolbarbutton:hover,
+.toolbarbutton-1:hover,
+.urlbar-page-action:hover {
+  background-color: var(--simhae-base02) !important;
+  color: var(--simhae-base07) !important;
+}
+
+toolbarbutton[open="true"],
+.toolbarbutton-1[open="true"] {
+  background-color: var(--simhae-base02) !important;
+  color: var(--simhae-base0c) !important;
+}
+
+#sidebar-header,
+sidebar-main,
+zen-sidebar,
+zen-workspaces-button,
+#zen-sidebar-top-buttons,
+#zen-sidebar-bottom-buttons {
+  background-color: var(--simhae-base00) !important;
+  color: var(--simhae-base05) !important;
+}
+
+#sidebar-box {
+  background-color: var(--simhae-base00) !important;
+  border: 3px solid var(--simhae-sidebar-reveal-border) !important;
+  border-radius: 12px !important;
+  box-shadow: none !important;
+  overflow: clip !important;
+}
+
+:root[sidebar-expand-on-hover] #sidebar-main:is(
+  [sidebar-launcher-expanded],
+  [sidebar-ongoing-animations]:not([sidebar-launcher-expanded])
+) {
+  background-image: none !important;
+  background-color: var(--simhae-base00) !important;
+  border-inline-end-color: var(--simhae-sidebar-reveal-border) !important;
+  border-inline-start-color: var(--simhae-sidebar-reveal-border) !important;
+  box-shadow: none !important;
+}
+
+#zen-tabbox-wrapper #sidebar-box {
+  box-shadow: none !important;
+}
+
+#sidebar-splitter,
+#sidebar-launcher-splitter,
+#zen-sidebar-splitter {
+  background: transparent !important;
+  border: none !important;
+  box-shadow: none !important;
+}
+
+#zen-sidebar-splitter {
+  --zen-primary-color: var(--simhae-sidebar-reveal-border) !important;
+  --button-background-color-primary: var(--simhae-sidebar-reveal-border) !important;
+}
+
+#zen-sidebar-splitter:hover {
+  background: var(--simhae-sidebar-reveal-border) !important;
+}
+
+#zen-sidebar-splitter::before {
+  background: var(--simhae-sidebar-reveal-border) !important;
+}
+
+#navigator-toolbox,
+#zen-tabbox-wrapper,
+#sidebar-main,
+#sidebar-box,
+#sidebar-splitter,
+#sidebar-launcher-splitter,
+#zen-sidebar-splitter {
+  --border-color: var(--simhae-sidebar-reveal-border) !important;
+  --border-color-deemphasized: var(--simhae-sidebar-reveal-border-muted) !important;
+  --border-color-interactive: var(--simhae-sidebar-reveal-border) !important;
+  --border-color-interactive-active: var(--simhae-sidebar-reveal-border) !important;
+  --border-color-interactive-disabled: var(--simhae-sidebar-reveal-border-muted) !important;
+  --border-color-interactive-hover: var(--simhae-sidebar-reveal-border) !important;
+}
+
+#sidebar-header,
+sidebar-main,
+zen-sidebar,
+zen-workspaces-button,
+#zen-sidebar-top-buttons,
+#zen-sidebar-bottom-buttons {
+  border: none !important;
+}
+
+#tabbrowser-tabpanels,
+#browser,
+#zen-main-app-wrapper,
+#tabbrowser-tabbox,
+#zen-appcontent-wrapper,
+.browserSidebarContainer,
+.browserSidebarContainer browser[type="content"] {
+  background: var(--simhae-base00) !important;
+}
+
+#zen-browser-background::before,
+#zen-browser-background::after {
+  background: var(--simhae-base00) !important;
+}
+
+.browserSidebarContainer {
+  border-radius: var(--zen-native-inner-radius) !important;
+}
+
+.browserSidebarContainer browser[type="content"] {
+  border: none !important;
+}
+
+#zen-workspaces-button toolbarbutton:hover,
+#zen-sidebar-top-buttons toolbarbutton:hover,
+#zen-sidebar-bottom-buttons toolbarbutton:hover {
+  background-color: var(--simhae-base02) !important;
+}
+
+menupopup,
+panel,
+panelview,
+dialog {
+  --panel-background: var(--simhae-base01) !important;
+  --panel-color: var(--simhae-base05) !important;
+  --panel-border-color: var(--simhae-base03) !important;
+}
+
+menu,
+menuitem,
+.subviewbutton {
+  color: var(--simhae-base05) !important;
+}
+
+menu:hover,
+menuitem:hover,
+.subviewbutton:hover {
+  background-color: var(--simhae-base02) !important;
+  color: var(--simhae-base07) !important;
+}
diff --git a/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/image.png b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/image.png
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index 000000000..983f0e24d
Binary files /dev/null and b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/image.png differ
diff --git a/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/readme.md b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/readme.md
new file mode 100644
index 000000000..84033e46b
--- /dev/null
+++ b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/readme.md
@@ -0,0 +1,15 @@
+
+# Simhae for Zen Browser
+
+Simhae is a dark Zen Browser theme built around a calm blue palette.
+
+## Features
+
+- Base00 dark browser shell and sidebar background
+  - URL popup styled with matching foreground, background, border, and divider
+  - Compact sidebar reveal frame matched to the Simhae palette
+  - Sidebar reveal border set to a soft alpha blue
+  - Toolbar reveal background fixed to avoid Zen's default near-black floating frame
+  - Tabs, toolbar buttons, panels, and menu hover states aligned with the theme
+
+Repository: https://github.com/spearkkk/simhae-zen
diff --git a/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/theme.json b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/theme.json
new file mode 100644
index 000000000..e1d7cf9a9
--- /dev/null
+++ b/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/theme.json
@@ -0,0 +1,14 @@
+{
+    "id": "28fb4c6c-8f52-4803-a793-18d3cada7098",
+    "name": "Simhae",
+    "description": "A calm dark blue theme with styled sidebar reveal and URL popup.",
+    "homepage": "https://github.com/spearkkk/simhae-zen",
+    "style": "https://raw.githubusercontent.com/zen-browser/theme-store/main/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/chrome.css",
+    "readme": "https://raw.githubusercontent.com/zen-browser/theme-store/main/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/readme.md",
+    "image": "https://raw.githubusercontent.com/zen-browser/theme-store/main/themes/28fb4c6c-8f52-4803-a793-18d3cada7098/image.png",
+    "author": "spearkkk",
+    "version": "1.0.0",
+    "tags": [],
+    "createdAt": "2026-07-10",
+    "updatedAt": "2026-07-10"
+}
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