diff --git a/.env b/.env
index 7ca84f1..2568130 100644
--- a/.env
+++ b/.env
@@ -1,2 +1,2 @@
-VITE_LAST_BUILD_DATE=20260623
-VITE_LAST_SUCCESSFUL_COMMIT=a89f454
+VITE_LAST_BUILD_DATE=20260625
+VITE_LAST_SUCCESSFUL_COMMIT=41e5f31
diff --git a/AGENTS.md b/AGENTS.md
index 5292adf..0b68b1a 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -70,6 +70,7 @@ __tests__/            # Jest tests
 - Change Log content is sourced from `src/data/toolkit/changelog.json`.
 - Credits Toolkit data is sourced from `src/data/toolkit/credits.json` and synced through the socket server.
 - Toolkit Images and Audio records can upload files through the socket into `src/assets/images/uploads/` and `src/assets/music/uploads/`.
+- Local Toolkit authoring uses `http://127.0.0.1:5175` by default so it does not collide with deployed socket automation.
 - Deployed Toolkit authoring uses `http://bone-kingdom.tabitha.tealthrone:5174` and intentionally runs from the shared repo workspace so edits update development JSON/assets while coding continues.
 - Toolkit seed datasets live under `src/data/toolkit/` and are exported through `src/data/index.ts`.
 - Shared data interfaces live under `src/data/types/`.
@@ -125,6 +126,17 @@ __tests__/            # Jest tests
 - Browser SCSS: `src/assets/scss/`
 - Add or update asset type declarations in `src/types/assets.d.ts` when needed.
 
+### Work with browser SCSS
+
+1. Use `src/assets/scss/index.scss` as the only browser SCSS entrypoint.
+2. Add design tokens and CSS custom properties in `__variables.scss`.
+3. Add shared browser mixins in `__mixins.scss`.
+4. Keep reset, root, and browser-wide element rules in `__globals.scss` and `__scrollbars.scss`.
+5. Put reusable `.blb-*` class builders in the concern-specific partials: `__typography.scss`, `__layout.scss`, `__surfaces.scss`, `__buttons.scss`, `__forms.scss`, and `__toolkit.scss`.
+6. Do not add ad hoc browser CSS in screen files. Add or extend a builder class in `src/assets/scss/`, then reference that class from the browser-only surface that needs it.
+7. Shared React Native screens and native-compatible components still use `StyleSheet.create()` unless a task explicitly asks for a web-only class-based migration.
+8. Keep browser-only class usage, DOM APIs, and web-specific styling assumptions inside `.web.tsx` files, `src/web/`, or explicitly browser-only surfaces.
+
 ## Commands
 
 ```bash
diff --git a/README.md b/README.md
index 9c83880..86c3c95 100644
--- a/README.md
+++ b/README.md
@@ -35,7 +35,7 @@ Starts the Vite browser app on `http://127.0.0.1:5173`.
 npm run dev:toolkit
 ```
 
-Starts the local Toolkit socket server on `http://127.0.0.1:5174`.
+Starts the local Toolkit socket server on `http://127.0.0.1:5175`.
 
 ```bash
 npm run dev:all
@@ -121,7 +121,7 @@ The Toolkit contains socket-backed structured forms for volatile gameplay system
 Socket health check:
 
 ```bash
-curl http://127.0.0.1:5174/health
+curl http://127.0.0.1:5175/health
 ```
 
 ## Shared Deploy Toolkit Socket
@@ -147,7 +147,9 @@ TOOLKIT_SOCKET_HOST=0.0.0.0 npm run deploy:toolkit
 
 ## Assets
 
-Image assets live in `src/assets/images/`. Fonts live in `src/assets/fonts/`. Music lives in `src/assets/music/`. Browser SCSS entrypoints live in `src/assets/scss/`.
+Image assets live in `src/assets/images/`. Fonts live in `src/assets/fonts/`. Music lives in `src/assets/music/`. Browser SCSS builders live in `src/assets/scss/`.
+
+`src/assets/scss/index.scss` is the only browser SCSS entrypoint. Builder partials separate tokens, mixins, globals, scrollbars, typography, layout, surfaces, buttons, forms, and Toolkit-specific class systems. Browser-only UI should reference reusable `.blb-*` classes from those builders instead of adding ad hoc CSS in feature files.
 
 The browser favicon is `src/assets/images/favicon.svg`.
 
diff --git a/__tests__/toolkitSocketClient.test.ts b/__tests__/toolkitSocketClient.test.ts
index 0e6230d..de21701 100644
--- a/__tests__/toolkitSocketClient.test.ts
+++ b/__tests__/toolkitSocketClient.test.ts
@@ -47,7 +47,7 @@ describe('toolkit socket client configuration', () => {
     delete process.env.TOOLKIT_SOCKET_URL;
     setTestLocation('localhost');
 
-    expect(getToolkitSocketUrl()).toBe('http://127.0.0.1:5174');
+    expect(getToolkitSocketUrl()).toBe('http://127.0.0.1:5175');
   });
 
   it('derives the deployed socket URL from the current browser host', () => {
diff --git a/llm.txt b/llm.txt
index f477867..f45c080 100644
--- a/llm.txt
+++ b/llm.txt
@@ -80,7 +80,7 @@ Vite resolves `.web.ts` before `.ts` (see `vite.config.ts` `resolve.extensions`)
 Shared stores import `./persistStorage`; the correct implementation is picked per bundler.
 
 ### Web entry
-`src/web/main.tsx` registers `App` via `AppRegistry.runApplication` against `#root` in `index.html`. Global styles: `src/assets/scss/index.scss`; image assets live under `src/assets/images/`.
+`src/web/main.tsx` registers `App` via `AppRegistry.runApplication` against `#root` in `index.html`. Browser styles enter through `src/assets/scss/index.scss`, which composes builder partials for variables, mixins, globals, scrollbars, typography, layout, surfaces, buttons, forms, and Toolkit classes. Image assets live under `src/assets/images/`.
 
 ### Electron shell
 - `electron/main.ts` — `BrowserWindow`, context isolation, no node integration
diff --git a/manifest.llm.json b/manifest.llm.json
index b371fb4..7156f77 100644
--- a/manifest.llm.json
+++ b/manifest.llm.json
@@ -116,7 +116,7 @@
       "runtime": "Node + Socket.IO",
       "entry": "socket/server.mjs",
       "devCommand": "npm run dev:toolkit",
-      "healthUrl": "http://127.0.0.1:5174/health",
+      "healthUrl": "http://127.0.0.1:5175/health",
       "deployCommand": "npm run deploy:toolkit",
       "deployHealthUrl": "http://bone-kingdom.tabitha.tealthrone:5174/health",
       "primary": true
@@ -255,6 +255,18 @@
       "fonts": "src/assets/fonts/",
       "music": "src/assets/music/",
       "scss": "src/assets/scss/",
+      "scssBuilders": [
+        "src/assets/scss/__variables.scss",
+        "src/assets/scss/__mixins.scss",
+        "src/assets/scss/__globals.scss",
+        "src/assets/scss/__scrollbars.scss",
+        "src/assets/scss/__typography.scss",
+        "src/assets/scss/__layout.scss",
+        "src/assets/scss/__surfaces.scss",
+        "src/assets/scss/__buttons.scss",
+        "src/assets/scss/__forms.scss",
+        "src/assets/scss/__toolkit.scss"
+      ],
       "favicon": "src/assets/images/favicon.svg"
     },
     "data": {
@@ -465,7 +477,7 @@
       ],
       "verify": [
         "npm run test -- --runInBand",
-        "npm run dev:toolkit and check http://127.0.0.1:5174/health"
+        "npm run dev:toolkit and check http://127.0.0.1:5175/health"
       ]
     },
     "mobile": {
@@ -621,7 +633,7 @@
     "socketChanges": [
       "npm run test -- --runInBand",
       "npm run dev:toolkit",
-      "curl http://127.0.0.1:5174/health",
+      "curl http://127.0.0.1:5175/health",
       "curl http://bone-kingdom.tabitha.tealthrone:5174/health"
     ],
     "mobileChanges": ["npm run lint", "npm run test -- --runInBand"],
diff --git a/package-lock.json b/package-lock.json
index 52f7fc5..2b45f8d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "BlbThroneOfTheBoneKing",
-  "version": "0.0.5",
+  "version": "0.0.7",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "BlbThroneOfTheBoneKing",
-      "version": "0.0.5",
+      "version": "0.0.7",
       "dependencies": {
         "@react-native-async-storage/async-storage": "^3.1.1",
         "@react-native/new-app-screen": "0.85.3",
diff --git a/package.json b/package.json
index 7ee5551..29fd3ab 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "BlbThroneOfTheBoneKing",
-  "version": "0.0.5",
+  "version": "0.0.7",
   "private": true,
   "main": "dist/electron/main.js",
   "scripts": {
diff --git a/socket/README.md b/socket/README.md
index 66bf988..d4cf01b 100644
--- a/socket/README.md
+++ b/socket/README.md
@@ -6,13 +6,13 @@ The Toolkit socket is a local/shared Socket.IO authoring server for browser-only
 
 ```bash
 npm run dev:toolkit
-curl http://127.0.0.1:5174/health
+curl http://127.0.0.1:5175/health
 ```
 
 Default local settings:
 
 - host: `127.0.0.1`
-- port: `5174`
+- port: `5175`
 - CORS origin: `http://127.0.0.1:5173`
 
 ## Shared Deployment
diff --git a/socket/clear.mjs b/socket/clear.mjs
index 1fdb87d..2d12d11 100644
--- a/socket/clear.mjs
+++ b/socket/clear.mjs
@@ -6,7 +6,7 @@ import { promisify } from 'node:util';
 const execFileAsync = promisify(execFile);
 const ports = [
   process.env.WEB_DEV_PORT ?? '5173',
-  process.env.TOOLKIT_SOCKET_PORT ?? '5174',
+  process.env.TOOLKIT_SOCKET_PORT ?? '5175',
 ];
 
 async function getPortProcessIds(port) {
diff --git a/socket/server.mjs b/socket/server.mjs
index 3c66984..54de313 100644
--- a/socket/server.mjs
+++ b/socket/server.mjs
@@ -16,7 +16,7 @@ const require = createRequire(import.meta.url);
 const packageJson = require('../package.json');
 const defaultWebOrigin = 'http://127.0.0.1:5173';
 const host = process.env.TOOLKIT_SOCKET_HOST ?? '127.0.0.1';
-const port = Number.parseInt(process.env.TOOLKIT_SOCKET_PORT ?? '5174', 10);
+const port = Number.parseInt(process.env.TOOLKIT_SOCKET_PORT ?? '5175', 10);
 const allowedOrigins = (
   process.env.TOOLKIT_SOCKET_CORS_ORIGIN ?? defaultWebOrigin
 )
diff --git a/src/assets/scss/__buttons.scss b/src/assets/scss/__buttons.scss
new file mode 100644
index 0000000..3a59eae
--- /dev/null
+++ b/src/assets/scss/__buttons.scss
@@ -0,0 +1,87 @@
+@use './__mixins' as mixins;
+@use './__variables' as variables;
+
+.blb-button {
+  @include mixins.control-reset;
+  @include mixins.gold-border;
+
+  align-items: center;
+  background: variables.$color-surface-strong;
+  border-radius: variables.$radius-control;
+  color: variables.$color-text;
+  display: inline-flex;
+  font-family: variables.$font-title;
+  gap: variables.$space-2;
+  justify-content: center;
+  min-height: variables.$control-height-md;
+  padding: variables.$space-2 variables.$space-3;
+  text-align: center;
+  transition:
+    background-color 120ms ease,
+    border-color 120ms ease,
+    color 120ms ease;
+}
+
+.blb-button:hover {
+  background: #2c2c2c;
+  border-color: variables.$color-gold;
+  color: variables.$color-gold-strong;
+}
+
+.blb-button:focus-visible {
+  @include mixins.focus-ring;
+}
+
+.blb-button:disabled,
+.blb-button[aria-disabled='true'] {
+  cursor: not-allowed;
+  opacity: 0.52;
+}
+
+.blb-button--toolkit {
+  background: variables.$color-surface-warm;
+  border-color: variables.$color-gold;
+  color: variables.$color-gold-strong;
+}
+
+.blb-button--danger {
+  border-color: variables.$color-danger;
+  color: #ffd8d8;
+}
+
+.blb-button--ghost {
+  background: transparent;
+}
+
+.blb-button--sharp {
+  @include mixins.sharp-control;
+
+  border-radius: variables.$radius-sharp;
+}
+
+.blb-button--compact {
+  min-height: variables.$control-height-sm;
+  padding: variables.$space-1 variables.$space-2;
+}
+
+.blb-button--icon {
+  aspect-ratio: 1;
+  min-height: variables.$control-height-sm;
+  padding: 0;
+  width: variables.$control-height-sm;
+}
+
+.blb-button-group {
+  align-items: stretch;
+  display: inline-flex;
+  gap: 0;
+}
+
+.blb-button-group .blb-button {
+  border-radius: 0;
+  margin-left: -1px;
+}
+
+.blb-button-group .blb-button:first-child {
+  margin-left: 0;
+}
diff --git a/src/assets/scss/__forms.scss b/src/assets/scss/__forms.scss
new file mode 100644
index 0000000..d205141
--- /dev/null
+++ b/src/assets/scss/__forms.scss
@@ -0,0 +1,81 @@
+@use './__mixins' as mixins;
+@use './__variables' as variables;
+
+.blb-field {
+  display: flex;
+  flex-direction: column;
+  gap: variables.$space-1;
+}
+
+.blb-field-row {
+  align-items: center;
+  display: grid;
+  gap: variables.$space-2;
+  grid-template-columns: minmax(120px, 0.4fr) minmax(0, 1fr);
+}
+
+.blb-control-label {
+  color: variables.$color-gold;
+  font-size: 12px;
+  text-transform: uppercase;
+}
+
+.blb-input,
+.blb-select,
+.blb-textarea {
+  @include mixins.gold-border;
+
+  background: #0d0f11;
+  border-radius: variables.$radius-control;
+  color: variables.$color-text;
+  min-height: variables.$control-height-md;
+  padding: variables.$space-2;
+  width: 100%;
+}
+
+.blb-input:focus,
+.blb-select:focus,
+.blb-textarea:focus {
+  @include mixins.focus-ring;
+}
+
+.blb-textarea {
+  min-height: 84px;
+  resize: vertical;
+}
+
+.blb-range {
+  accent-color: variables.$color-gold;
+  width: 100%;
+}
+
+.blb-checkbox {
+  accent-color: variables.$color-gold;
+  height: 18px;
+  width: 18px;
+}
+
+.blb-form-grid {
+  display: grid;
+  gap: variables.$space-3;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+}
+
+.blb-icon-action {
+  @include mixins.control-reset;
+  @include mixins.gold-border;
+
+  align-items: center;
+  background: variables.$color-surface-strong;
+  border-radius: variables.$radius-control;
+  color: variables.$color-gold-strong;
+  display: inline-flex;
+  height: variables.$control-height-sm;
+  justify-content: center;
+  width: variables.$control-height-sm;
+}
+
+.blb-icon-action:hover,
+.blb-icon-action:focus-visible {
+  @include mixins.focus-ring;
+}
diff --git a/src/assets/scss/__globals.scss b/src/assets/scss/__globals.scss
index 2ce4dec..497380e 100644
--- a/src/assets/scss/__globals.scss
+++ b/src/assets/scss/__globals.scss
@@ -1,19 +1,5 @@
 @use './__variables' as variables;
 
-@font-face {
-  font-family: 'MiTicaRegular';
-  font-style: normal;
-  font-weight: normal;
-  src: url('../fonts/mitica/MiTicaRegular.otf') format('opentype');
-}
-
-@font-face {
-  font-family: 'SingleDayRegular';
-  font-style: normal;
-  font-weight: normal;
-  src: url('../fonts/single-day/SingleDayRegular.ttf') format('truetype');
-}
-
 html,
 body,
 #root {
@@ -24,35 +10,25 @@ body,
 
 body {
   background: variables.$color-page-background;
-  font-family: 'SingleDayRegular', sans-serif;
+  color: variables.$color-text;
+  font-family: variables.$font-body;
   overflow: hidden;
 }
 
-* {
-  scrollbar-color: #d6b25e #111315;
-  scrollbar-width: thin;
+*,
+*::before,
+*::after {
+  box-sizing: border-box;
 }
 
-*::-webkit-scrollbar {
-  height: 10px;
-  width: 10px;
-}
-
-*::-webkit-scrollbar-track {
-  background: #111315;
-  border-left: 1px solid #2d2f32;
-}
-
-*::-webkit-scrollbar-thumb {
-  background: #3a3120;
-  border: 1px solid #d6b25e;
-  border-radius: 2px;
-}
-
-*::-webkit-scrollbar-thumb:hover {
-  background: #4a3a22;
+button,
+input,
+select,
+textarea {
+  font: inherit;
 }
 
 #root {
   display: flex;
+  width: 100%;
 }
diff --git a/src/assets/scss/__layout.scss b/src/assets/scss/__layout.scss
new file mode 100644
index 0000000..510651e
--- /dev/null
+++ b/src/assets/scss/__layout.scss
@@ -0,0 +1,77 @@
+@use './__variables' as variables;
+
+.blb-fill {
+  height: 100%;
+  min-height: 0;
+  width: 100%;
+}
+
+.blb-page {
+  background: variables.$color-page-background;
+  color: variables.$color-text;
+  min-height: 100%;
+  overflow: hidden;
+}
+
+.blb-landscape-stage {
+  aspect-ratio: 16 / 9;
+  margin: 0 auto;
+  max-height: 100%;
+  max-width: 100%;
+  overflow: hidden;
+  position: relative;
+}
+
+.blb-stack {
+  display: flex;
+  flex-direction: column;
+  gap: variables.$space-3;
+}
+
+.blb-stack--tight {
+  gap: variables.$space-1;
+}
+
+.blb-cluster {
+  align-items: center;
+  display: flex;
+  flex-wrap: wrap;
+  gap: variables.$space-2;
+}
+
+.blb-split {
+  align-items: stretch;
+  display: flex;
+  gap: variables.$space-4;
+  justify-content: space-between;
+}
+
+.blb-grid-2 {
+  display: grid;
+  gap: variables.$space-4;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+}
+
+.blb-grid-3 {
+  display: grid;
+  gap: variables.$space-3;
+  grid-template-columns: repeat(3, minmax(0, 1fr));
+}
+
+.blb-toolbar {
+  align-items: center;
+  display: flex;
+  gap: 0;
+  min-height: variables.$control-height-sm;
+}
+
+.blb-toolbar-spacer {
+  flex: 1 1 auto;
+}
+
+.blb-fixed-bottom-right {
+  bottom: variables.$space-3;
+  position: fixed;
+  right: variables.$space-3;
+  z-index: variables.$z-status;
+}
diff --git a/src/assets/scss/__mixins.scss b/src/assets/scss/__mixins.scss
new file mode 100644
index 0000000..fb33f9d
--- /dev/null
+++ b/src/assets/scss/__mixins.scss
@@ -0,0 +1,35 @@
+@use './__variables' as variables;
+
+@mixin focus-ring {
+  outline: 2px solid variables.$color-gold-strong;
+  outline-offset: 2px;
+}
+
+@mixin control-reset {
+  appearance: none;
+  background: transparent;
+  border: 0;
+  color: inherit;
+  cursor: pointer;
+  font: inherit;
+  margin: 0;
+  padding: 0;
+}
+
+@mixin gold-border($color: variables.$color-border) {
+  border: 1px solid $color;
+  box-shadow: inset 0 0 0 1px rgba(214, 178, 94, 0.08);
+}
+
+@mixin panel-surface {
+  @include gold-border;
+
+  background: variables.$color-surface-raised;
+  border-radius: variables.$radius-panel;
+  box-shadow: 0 16px 40px variables.$color-shadow;
+}
+
+@mixin sharp-control {
+  border-radius: variables.$radius-sharp;
+  min-height: variables.$control-height-sm;
+}
diff --git a/src/assets/scss/__scrollbars.scss b/src/assets/scss/__scrollbars.scss
new file mode 100644
index 0000000..46b9752
--- /dev/null
+++ b/src/assets/scss/__scrollbars.scss
@@ -0,0 +1,26 @@
+@use './__variables' as variables;
+
+* {
+  scrollbar-color: variables.$color-gold #111315;
+  scrollbar-width: thin;
+}
+
+*::-webkit-scrollbar {
+  height: 10px;
+  width: 10px;
+}
+
+*::-webkit-scrollbar-track {
+  background: #111315;
+  border-left: 1px solid #2d2f32;
+}
+
+*::-webkit-scrollbar-thumb {
+  background: #3a3120;
+  border: 1px solid variables.$color-gold;
+  border-radius: 2px;
+}
+
+*::-webkit-scrollbar-thumb:hover {
+  background: #4a3a22;
+}
diff --git a/src/assets/scss/__surfaces.scss b/src/assets/scss/__surfaces.scss
new file mode 100644
index 0000000..76fdbbc
--- /dev/null
+++ b/src/assets/scss/__surfaces.scss
@@ -0,0 +1,57 @@
+@use './__mixins' as mixins;
+@use './__variables' as variables;
+
+.blb-panel {
+  @include mixins.panel-surface;
+
+  padding: variables.$space-4;
+}
+
+.blb-panel--dense {
+  padding: variables.$space-2;
+}
+
+.blb-panel--flat {
+  box-shadow: none;
+}
+
+.blb-card {
+  @include mixins.gold-border;
+
+  background: variables.$color-surface;
+  border-radius: variables.$radius-control;
+  padding: variables.$space-3;
+}
+
+.blb-frame {
+  @include mixins.gold-border(variables.$color-border-strong);
+
+  background: rgba(5, 6, 7, 0.72);
+  border-radius: variables.$radius-panel;
+  overflow: hidden;
+}
+
+.blb-divider {
+  background: variables.$color-border;
+  height: 1px;
+  width: 100%;
+}
+
+.blb-socket-dot {
+  border-radius: 999px;
+  display: inline-block;
+  height: 10px;
+  width: 10px;
+}
+
+.blb-socket-dot--connected {
+  background: variables.$color-success;
+}
+
+.blb-socket-dot--connecting {
+  background: variables.$color-warning;
+}
+
+.blb-socket-dot--disconnected {
+  background: variables.$color-danger;
+}
diff --git a/src/assets/scss/__toolkit.scss b/src/assets/scss/__toolkit.scss
new file mode 100644
index 0000000..c75e85b
--- /dev/null
+++ b/src/assets/scss/__toolkit.scss
@@ -0,0 +1,62 @@
+@use './__mixins' as mixins;
+@use './__variables' as variables;
+
+.blb-toolkit {
+  background: variables.$color-page-background;
+  color: variables.$color-text;
+  display: grid;
+  grid-template-rows: auto minmax(0, 1fr);
+  height: 100%;
+  overflow: hidden;
+}
+
+.blb-toolkit-toolbar {
+  align-items: stretch;
+  background: #080a0b;
+  border-bottom: 1px solid variables.$color-border;
+  display: flex;
+  min-height: variables.$control-height-sm;
+  z-index: variables.$z-toolbar;
+}
+
+.blb-toolkit-window {
+  min-height: 0;
+  overflow: auto;
+  padding: variables.$space-3;
+}
+
+.blb-toolkit-record-list {
+  display: flex;
+  flex-direction: column;
+  gap: variables.$space-1;
+  min-width: 160px;
+}
+
+.blb-toolkit-record {
+  @include mixins.gold-border;
+
+  background: variables.$color-surface;
+  border-radius: variables.$radius-control;
+  color: variables.$color-text;
+  padding: variables.$space-2;
+}
+
+.blb-toolkit-record--active {
+  background: variables.$color-surface-warm;
+  border-color: variables.$color-gold;
+}
+
+.blb-toolkit-editor {
+  min-width: 0;
+  overflow: auto;
+}
+
+.blb-toolkit-status {
+  align-items: center;
+  bottom: variables.$space-2;
+  display: inline-flex;
+  gap: variables.$space-1;
+  position: fixed;
+  right: variables.$space-2;
+  z-index: variables.$z-status;
+}
diff --git a/src/assets/scss/__typography.scss b/src/assets/scss/__typography.scss
new file mode 100644
index 0000000..c10187e
--- /dev/null
+++ b/src/assets/scss/__typography.scss
@@ -0,0 +1,83 @@
+@use './__variables' as variables;
+
+@font-face {
+  font-family: 'MiTicaRegular';
+  font-style: normal;
+  font-weight: normal;
+  src: url('../fonts/mitica/MiTicaRegular.otf') format('opentype');
+}
+
+@font-face {
+  font-family: 'SingleDayRegular';
+  font-style: normal;
+  font-weight: normal;
+  src: url('../fonts/single-day/SingleDayRegular.ttf') format('truetype');
+}
+
+.blb-font-title {
+  font-family: variables.$font-title;
+}
+
+.blb-font-body {
+  font-family: variables.$font-body;
+}
+
+.blb-heading-xl,
+.blb-heading-lg,
+.blb-heading-md,
+.blb-control-label {
+  color: variables.$color-text;
+  font-family: variables.$font-title;
+  letter-spacing: 0;
+  margin: 0;
+}
+
+.blb-heading-xl {
+  font-size: 42px;
+  line-height: 1;
+}
+
+.blb-heading-lg {
+  font-size: 30px;
+  line-height: 1.05;
+}
+
+.blb-heading-md {
+  font-size: 20px;
+  line-height: 1.1;
+}
+
+.blb-body-copy {
+  color: variables.$color-text;
+  font-family: variables.$font-body;
+  font-size: 16px;
+  line-height: 1.35;
+  margin: 0;
+}
+
+.blb-small-copy,
+.blb-kicker {
+  color: variables.$color-text-muted;
+  font-family: variables.$font-body;
+  font-size: 12px;
+  line-height: 1.2;
+  margin: 0;
+}
+
+.blb-kicker {
+  color: variables.$color-gold;
+  font-family: variables.$font-title;
+  text-transform: uppercase;
+}
+
+.blb-text-gold {
+  color: variables.$color-gold-strong;
+}
+
+.blb-text-muted {
+  color: variables.$color-text-muted;
+}
+
+.blb-text-dim {
+  color: variables.$color-text-dim;
+}
diff --git a/src/assets/scss/__variables.scss b/src/assets/scss/__variables.scss
index 05cfe71..236a24c 100644
--- a/src/assets/scss/__variables.scss
+++ b/src/assets/scss/__variables.scss
@@ -1 +1,62 @@
+$font-title: 'MiTicaRegular', serif;
+$font-body: 'SingleDayRegular', sans-serif;
+
 $color-page-background: #050607;
+$color-surface: #111518;
+$color-surface-raised: #171b1f;
+$color-surface-strong: #232323;
+$color-surface-warm: #3a2a12;
+$color-text: #f8f1dd;
+$color-text-muted: #b9ad96;
+$color-text-dim: #7d745f;
+$color-gold: #d6b25e;
+$color-gold-strong: #f5d67b;
+$color-gold-dim: #80642f;
+$color-border: #3b3326;
+$color-border-strong: #72582b;
+$color-danger: #b44747;
+$color-success: #61d47a;
+$color-warning: #d7bb52;
+$color-shadow: rgba(0, 0, 0, 0.42);
+
+$space-1: 4px;
+$space-2: 8px;
+$space-3: 12px;
+$space-4: 16px;
+$space-5: 20px;
+$space-6: 24px;
+$space-8: 32px;
+
+$radius-sharp: 0;
+$radius-control: 4px;
+$radius-panel: 6px;
+
+$control-height-sm: 28px;
+$control-height-md: 38px;
+$control-height-lg: 46px;
+
+$z-overlay: 20;
+$z-toolbar: 30;
+$z-status: 40;
+
+:root {
+  --blb-font-title: #{$font-title};
+  --blb-font-body: #{$font-body};
+  --blb-color-page-background: #{$color-page-background};
+  --blb-color-surface: #{$color-surface};
+  --blb-color-surface-raised: #{$color-surface-raised};
+  --blb-color-surface-strong: #{$color-surface-strong};
+  --blb-color-surface-warm: #{$color-surface-warm};
+  --blb-color-text: #{$color-text};
+  --blb-color-text-muted: #{$color-text-muted};
+  --blb-color-text-dim: #{$color-text-dim};
+  --blb-color-gold: #{$color-gold};
+  --blb-color-gold-strong: #{$color-gold-strong};
+  --blb-color-gold-dim: #{$color-gold-dim};
+  --blb-color-border: #{$color-border};
+  --blb-color-border-strong: #{$color-border-strong};
+  --blb-color-danger: #{$color-danger};
+  --blb-color-success: #{$color-success};
+  --blb-color-warning: #{$color-warning};
+  --blb-shadow: #{$color-shadow};
+}
diff --git a/src/assets/scss/index.scss b/src/assets/scss/index.scss
index e385542..ac69816 100644
--- a/src/assets/scss/index.scss
+++ b/src/assets/scss/index.scss
@@ -1 +1,13 @@
+// Browser style builder entrypoint.
+// Add new web class systems as partials here; keep component code referencing
+// the generated .blb-* classes instead of defining ad hoc browser CSS.
+@use './__variables';
+@use './__mixins';
+@use './__typography';
 @use './__globals';
+@use './__scrollbars';
+@use './__layout';
+@use './__surfaces';
+@use './__buttons';
+@use './__forms';
+@use './__toolkit';
diff --git a/src/data/toolkit/changelog.json b/src/data/toolkit/changelog.json
index f4ff78a..8fecdbd 100644
--- a/src/data/toolkit/changelog.json
+++ b/src/data/toolkit/changelog.json
@@ -1,4 +1,16 @@
 [
+  {
+    "id": "browser-scss-builder-system",
+    "version": "0.0.5-20260625-local",
+    "createdAt": "2026-06-25",
+    "title": "Browser SCSS Builder System",
+    "summary": "Added a separated browser styling builder layer and moved local Toolkit socket defaults away from the deployed socket port.",
+    "changes": [
+      "Added SCSS builder partials for variables, mixins, typography, layout, surfaces, buttons, forms, scrollbars, and Toolkit-specific classes.",
+      "Documented the styling boundary between browser class builders and native-compatible React Native StyleSheet usage.",
+      "Changed the local Toolkit socket default port to 5175 while keeping deployed Toolkit automation on 5174."
+    ]
+  },
   {
     "id": "woodpecker-gitea-endpoint-fix",
     "version": "0.0.5-20260624-local",
diff --git a/src/socket/toolkitSocketClient.ts b/src/socket/toolkitSocketClient.ts
index 73bfe95..e6db755 100644
--- a/src/socket/toolkitSocketClient.ts
+++ b/src/socket/toolkitSocketClient.ts
@@ -81,7 +81,8 @@ type ToolkitAssetUploadResponse =
   | ToolkitAssetUploadSuccessResponse
   | ToolkitAssetUploadErrorResponse;
 
-const defaultToolkitSocketUrl = 'http://127.0.0.1:5174';
+const defaultToolkitSocketUrl = 'http://127.0.0.1:5175';
+const deployedToolkitSocketPort = '5174';
 const toolkitSocketTimeoutMs = 5000;
 
 let toolkitSocket: Socket | null = null;
@@ -112,7 +113,7 @@ function getBrowserToolkitSocketUrl() {
     return defaultToolkitSocketUrl;
   }
 
-  return `${location.protocol}//${location.hostname}:5174`;
+  return `${location.protocol}//${location.hostname}:${deployedToolkitSocketPort}`;
 }
 
 export function getToolkitSocketUrl() {