Vanilla JS (v3): Implement 3-pane layout, item fetching, reading, and testing

16 files changed, 1737 insertions, 100 deletions

diff --git a/frontend-vanilla/package-lock.json b/frontend-vanilla/package-lock.json
index 6f6c92e..8a82676 100644
--- a/frontend-vanilla/package-lock.json
+++ b/frontend-vanilla/package-lock.json
@@ -8,8 +8,226 @@
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@@ -428,6 +646,29 @@
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+      "dev": true,
+      "dependencies": {
+        "indent-string": "^4.0.0",
+        "strip-indent": "^3.0.0"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
+    "node_modules/require-from-string": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/require-from-string/-/require-from-string-2.0.2.tgz",
+      "integrity": "sha512-Xf0nWe6RseziFMu+Ap9biiUbmplq6S9/p+7w7YXP/JBHhrUDDUhwa+vANyubuqfZWTveU//DYVGsDG7RKL/vEw==",
+      "dev": true,
+      "engines": {
+        "node": ">=0.10.0"
+      }
+    },
     "node_modules/rollup": {
       "version": "4.57.1",
       "resolved": "https://registry.npmjs.org/rollup/-/rollup-4.57.1.tgz",
@@ -939,6 +1769,24 @@
         "fsevents": "~2.3.2"
       }
     },
+    "node_modules/saxes": {
+      "version": "6.0.0",
+      "resolved": "https://registry.npmjs.org/saxes/-/saxes-6.0.0.tgz",
+      "integrity": "sha512-xAg7SOnEhrm5zI3puOOKyy1OMcMlIJZYNJY7xLBwSze0UjhPLnWfj2GF2EpT0jmzaJKIWKHLsaSSajf35bcYnA==",
+      "dev": true,
+      "dependencies": {
+        "xmlchars": "^2.2.0"
+      },
+      "engines": {
+        "node": ">=v12.22.7"
+      }
+    },
+    "node_modules/siginfo": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/siginfo/-/siginfo-2.0.0.tgz",
+      "integrity": "sha512-ybx0WO1/8bSBLEWXZvEd7gMW3Sn3JFlW3TvX1nREbDLRNQNaeNN8WK0meBwPdAaOI7TtRRRJn/Es1zhrrCHu7g==",
+      "dev": true
+    },
     "node_modules/source-map-js": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/source-map-js/-/source-map-js-1.2.1.tgz",
@@ -948,6 +1796,51 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/stackback": {
+      "version": "0.0.2",
+      "resolved": "https://registry.npmjs.org/stackback/-/stackback-0.0.2.tgz",
+      "integrity": "sha512-1XMJE5fQo1jGH6Y/7ebnwPOBEkIEnT4QF32d5R1+VXdXveM0IBMJt8zfaxX1P3QhVwrYe+576+jkANtSS2mBbw==",
+      "dev": true
+    },
+    "node_modules/std-env": {
+      "version": "3.10.0",
+      "resolved": "https://registry.npmjs.org/std-env/-/std-env-3.10.0.tgz",
+      "integrity": "sha512-5GS12FdOZNliM5mAOxFRg7Ir0pWz8MdpYm6AY6VPkGpbA7ZzmbzNcBJQ0GPvvyWgcY7QAhCgf9Uy89I03faLkg==",
+      "dev": true
+    },
+    "node_modules/strip-indent": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/strip-indent/-/strip-indent-3.0.0.tgz",
+      "integrity": "sha512-laJTa3Jb+VQpaC6DseHhF7dXVqHTfJPCRDaEbid/drOhgitgYku/letMUqOXFoWV0zIIUbjpdH2t+tYj4bQMRQ==",
+      "dev": true,
+      "dependencies": {
+        "min-indent": "^1.0.0"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
+    "node_modules/symbol-tree": {
+      "version": "3.2.4",
+      "resolved": "https://registry.npmjs.org/symbol-tree/-/symbol-tree-3.2.4.tgz",
+      "integrity": "sha512-9QNk5KwDF+Bvz+PyObkmSYjI5ksVUYtjW7AU22r2NKcfLJcXp96hkDWU3+XndOsUb+AQ9QhfzfCT2O+CNWT5Tw==",
+      "dev": true
+    },
+    "node_modules/tinybench": {
+      "version": "2.9.0",
+      "resolved": "https://registry.npmjs.org/tinybench/-/tinybench-2.9.0.tgz",
+      "integrity": "sha512-0+DUvqWMValLmha6lr4kD8iAMK1HzV0/aKnCtWb9v9641TnP/MFb7Pc2bxoxQjTXAErryXVgUOfv2YqNllqGeg==",
+      "dev": true
+    },
+    "node_modules/tinyexec": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/tinyexec/-/tinyexec-1.0.2.tgz",
+      "integrity": "sha512-W/KYk+NFhkmsYpuHq5JykngiOCnxeVL8v8dFnqxSD8qEEdRfXk1SDM6JzNqcERbcGYj9tMrDQBYV9cjgnunFIg==",
+      "dev": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
     "node_modules/tinyglobby": {
       "version": "0.2.15",
       "resolved": "https://registry.npmjs.org/tinyglobby/-/tinyglobby-0.2.15.tgz",
@@ -964,6 +1857,57 @@
         "url": "https://github.com/sponsors/SuperchupuDev"
       }
     },
+    "node_modules/tinyrainbow": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/tinyrainbow/-/tinyrainbow-3.0.3.tgz",
+      "integrity": "sha512-PSkbLUoxOFRzJYjjxHJt9xro7D+iilgMX/C9lawzVuYiIdcihh9DXmVibBe8lmcFrRi/VzlPjBxbN7rH24q8/Q==",
+      "dev": true,
+      "engines": {
+        "node": ">=14.0.0"
+      }
+    },
+    "node_modules/tldts": {
+      "version": "7.0.23",
+      "resolved": "https://registry.npmjs.org/tldts/-/tldts-7.0.23.tgz",
+      "integrity": "sha512-ASdhgQIBSay0R/eXggAkQ53G4nTJqTXqC2kbaBbdDwM7SkjyZyO0OaaN1/FH7U/yCeqOHDwFO5j8+Os/IS1dXw==",
+      "dev": true,
+      "dependencies": {
+        "tldts-core": "^7.0.23"
+      },
+      "bin": {
+        "tldts": "bin/cli.js"
+      }
+    },
+    "node_modules/tldts-core": {
+      "version": "7.0.23",
+      "resolved": "https://registry.npmjs.org/tldts-core/-/tldts-core-7.0.23.tgz",
+      "integrity": "sha512-0g9vrtDQLrNIiCj22HSe9d4mLVG3g5ph5DZ8zCKBr4OtrspmNB6ss7hVyzArAeE88ceZocIEGkyW1Ime7fxPtQ==",
+      "dev": true
+    },
+    "node_modules/tough-cookie": {
+      "version": "6.0.0",
+      "resolved": "https://registry.npmjs.org/tough-cookie/-/tough-cookie-6.0.0.tgz",
+      "integrity": "sha512-kXuRi1mtaKMrsLUxz3sQYvVl37B0Ns6MzfrtV5DvJceE9bPyspOqk9xxv7XbZWcfLWbFmm997vl83qUWVJA64w==",
+      "dev": true,
+      "dependencies": {
+        "tldts": "^7.0.5"
+      },
+      "engines": {
+        "node": ">=16"
+      }
+    },
+    "node_modules/tr46": {
+      "version": "6.0.0",
+      "resolved": "https://registry.npmjs.org/tr46/-/tr46-6.0.0.tgz",
+      "integrity": "sha512-bLVMLPtstlZ4iMQHpFHTR7GAGj2jxi8Dg0s2h2MafAE4uSWF98FC/3MomU51iQAMf8/qDUbKWf5GxuvvVcXEhw==",
+      "dev": true,
+      "dependencies": {
+        "punycode": "^2.3.1"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
     "node_modules/typescript": {
       "version": "5.9.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
@@ -977,6 +1921,15 @@
         "node": ">=14.17"
       }
     },
+    "node_modules/undici": {
+      "version": "7.22.0",
+      "resolved": "https://registry.npmjs.org/undici/-/undici-7.22.0.tgz",
+      "integrity": "sha512-RqslV2Us5BrllB+JeiZnK4peryVTndy9Dnqq62S3yYRRTj0tFQCwEniUy2167skdGOy3vqRzEvl1Dm4sV2ReDg==",
+      "dev": true,
+      "engines": {
+        "node": ">=20.18.1"
+      }
+    },
     "node_modules/vite": {
       "version": "7.3.1",
       "resolved": "https://registry.npmjs.org/vite/-/vite-7.3.1.tgz",
@@ -1050,6 +2003,158 @@
           "optional": true
         }
       }
+    },
+    "node_modules/vitest": {
+      "version": "4.0.18",
+      "resolved": "https://registry.npmjs.org/vitest/-/vitest-4.0.18.tgz",
+      "integrity": "sha512-hOQuK7h0FGKgBAas7v0mSAsnvrIgAvWmRFjmzpJ7SwFHH3g1k2u37JtYwOwmEKhK6ZO3v9ggDBBm0La1LCK4uQ==",
+      "dev": true,
+      "dependencies": {
+        "@vitest/expect": "4.0.18",
+        "@vitest/mocker": "4.0.18",
+        "@vitest/pretty-format": "4.0.18",
+        "@vitest/runner": "4.0.18",
+        "@vitest/snapshot": "4.0.18",
+        "@vitest/spy": "4.0.18",
+        "@vitest/utils": "4.0.18",
+        "es-module-lexer": "^1.7.0",
+        "expect-type": "^1.2.2",
+        "magic-string": "^0.30.21",
+        "obug": "^2.1.1",
+        "pathe": "^2.0.3",
+        "picomatch": "^4.0.3",
+        "std-env": "^3.10.0",
+        "tinybench": "^2.9.0",
+        "tinyexec": "^1.0.2",
+        "tinyglobby": "^0.2.15",
+        "tinyrainbow": "^3.0.3",
+        "vite": "^6.0.0 || ^7.0.0",
+        "why-is-node-running": "^2.3.0"
+      },
+      "bin": {
+        "vitest": "vitest.mjs"
+      },
+      "engines": {
+        "node": "^20.0.0 || ^22.0.0 || >=24.0.0"
+      },
+      "funding": {
+        "url": "https://opencollective.com/vitest"
+      },
+      "peerDependencies": {
+        "@edge-runtime/vm": "*",
+        "@opentelemetry/api": "^1.9.0",
+        "@types/node": "^20.0.0 || ^22.0.0 || >=24.0.0",
+        "@vitest/browser-playwright": "4.0.18",
+        "@vitest/browser-preview": "4.0.18",
+        "@vitest/browser-webdriverio": "4.0.18",
+        "@vitest/ui": "4.0.18",
+        "happy-dom": "*",
+        "jsdom": "*"
+      },
+      "peerDependenciesMeta": {
+        "@edge-runtime/vm": {
+          "optional": true
+        },
+        "@opentelemetry/api": {
+          "optional": true
+        },
+        "@types/node": {
+          "optional": true
+        },
+        "@vitest/browser-playwright": {
+          "optional": true
+        },
+        "@vitest/browser-preview": {
+          "optional": true
+        },
+        "@vitest/browser-webdriverio": {
+          "optional": true
+        },
+        "@vitest/ui": {
+          "optional": true
+        },
+        "happy-dom": {
+          "optional": true
+        },
+        "jsdom": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/w3c-xmlserializer": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/w3c-xmlserializer/-/w3c-xmlserializer-5.0.0.tgz",
+      "integrity": "sha512-o8qghlI8NZHU1lLPrpi2+Uq7abh4GGPpYANlalzWxyWteJOCsr/P+oPBA49TOLu5FTZO4d3F9MnWJfiMo4BkmA==",
+      "dev": true,
+      "dependencies": {
+        "xml-name-validator": "^5.0.0"
+      },
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/webidl-conversions": {
+      "version": "8.0.1",
+      "resolved": "https://registry.npmjs.org/webidl-conversions/-/webidl-conversions-8.0.1.tgz",
+      "integrity": "sha512-BMhLD/Sw+GbJC21C/UgyaZX41nPt8bUTg+jWyDeg7e7YN4xOM05YPSIXceACnXVtqyEw/LMClUQMtMZ+PGGpqQ==",
+      "dev": true,
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/whatwg-mimetype": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/whatwg-mimetype/-/whatwg-mimetype-5.0.0.tgz",
+      "integrity": "sha512-sXcNcHOC51uPGF0P/D4NVtrkjSU2fNsm9iog4ZvZJsL3rjoDAzXZhkm2MWt1y+PUdggKAYVoMAIYcs78wJ51Cw==",
+      "dev": true,
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/whatwg-url": {
+      "version": "16.0.0",
+      "resolved": "https://registry.npmjs.org/whatwg-url/-/whatwg-url-16.0.0.tgz",
+      "integrity": "sha512-9CcxtEKsf53UFwkSUZjG+9vydAsFO4lFHBpJUtjBcoJOCJpKnSJNwCw813zrYJHpCJ7sgfbtOe0V5Ku7Pa1XMQ==",
+      "dev": true,
+      "dependencies": {
+        "@exodus/bytes": "^1.11.0",
+        "tr46": "^6.0.0",
+        "webidl-conversions": "^8.0.1"
+      },
+      "engines": {
+        "node": "^20.19.0 || ^22.12.0 || >=24.0.0"
+      }
+    },
+    "node_modules/why-is-node-running": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/why-is-node-running/-/why-is-node-running-2.3.0.tgz",
+      "integrity": "sha512-hUrmaWBdVDcxvYqnyh09zunKzROWjbZTiNy8dBEjkS7ehEDQibXJ7XvlmtbwuTclUiIyN+CyXQD4Vmko8fNm8w==",
+      "dev": true,
+      "dependencies": {
+        "siginfo": "^2.0.0",
+        "stackback": "0.0.2"
+      },
+      "bin": {
+        "why-is-node-running": "cli.js"
+      },
+      "engines": {
+        "node": ">=8"
+      }
+    },
+    "node_modules/xml-name-validator": {
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/xml-name-validator/-/xml-name-validator-5.0.0.tgz",
+      "integrity": "sha512-EvGK8EJ3DhaHfbRlETOWAS5pO9MZITeauHKJyb8wyajUfQUenkIg2MvLDTZ4T/TgIcm3HU0TFBgWWboAZ30UHg==",
+      "dev": true,
+      "engines": {
+        "node": ">=18"
+      }
+    },
+    "node_modules/xmlchars": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/xmlchars/-/xmlchars-2.2.0.tgz",
+      "integrity": "sha512-JZnDKK8B0RCDw84FNdDAIpZK+JuJw+s7Lz8nksI7SIuU3UXJJslUthsi+uWBUYOwPFwW7W7PRLRfUKpxjtjFCw==",
+      "dev": true
     }
   }
 }
diff --git a/frontend-vanilla/package.json b/frontend-vanilla/package.json
index ee57be1..65e19b2 100644
--- a/frontend-vanilla/package.json
+++ b/frontend-vanilla/package.json
@@ -6,10 +6,15 @@
   "scripts": {
     "dev": "vite",
     "build": "tsc && vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "test": "vitest"
   },
   "devDependencies": {
+    "@testing-library/dom": "^10.4.1",
+    "@testing-library/jest-dom": "^6.9.1",
+    "jsdom": "^28.1.0",
     "typescript": "~5.9.3",
-    "vite": "^7.3.1"
+    "vite": "^7.3.1",
+    "vitest": "^4.0.18"
   }
-}
+}
\ No newline at end of file
diff --git a/frontend-vanilla/public/vite.svg b/frontend-vanilla/public/vite.svg
deleted file mode 100644
index e7b8dfb..0000000
--- a/frontend-vanilla/public/vite.svg
+++ /dev/null
@@ -1 +0,0 @@
-<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" class="iconify iconify--logos" width="31.88" height="32" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 257"><defs><linearGradient id="IconifyId1813088fe1fbc01fb466" x1="-.828%" x2="57.636%" y1="7.652%" y2="78.411%"><stop offset="0%" stop-color="#41D1FF"></stop><stop offset="100%" stop-color="#BD34FE"></stop></linearGradient><linearGradient id="IconifyId1813088fe1fbc01fb467" x1="43.376%" x2="50.316%" y1="2.242%" y2="89.03%"><stop offset="0%" stop-color="#FFEA83"></stop><stop offset="8.333%" stop-color="#FFDD35"></stop><stop offset="100%" stop-color="#FFA800"></stop></linearGradient></defs><path fill="url(#IconifyId1813088fe1fbc01fb466)" d="M255.153 37.938L134.897 252.976c-2.483 4.44-8.862 4.466-11.382.048L.875 37.958c-2.746-4.814 1.371-10.646 6.827-9.67l120.385 21.517a6.537 6.537 0 0 0 2.322-.004l117.867-21.483c5.438-.991 9.574 4.796 6.877 9.62Z"></path><path fill="url(#IconifyId1813088fe1fbc01fb467)" d="M185.432.063L96.44 17.501a3.268 3.268 0 0 0-2.634 3.014l-5.474 92.456a3.268 3.268 0 0 0 3.997 3.378l24.777-5.718c2.318-.535 4.413 1.507 3.936 3.838l-7.361 36.047c-.495 2.426 1.782 4.5 4.151 3.78l15.304-4.649c2.372-.72 4.652 1.36 4.15 3.788l-11.698 56.621c-.732 3.542 3.979 5.473 5.943 2.437l1.313-2.028l72.516-144.72c1.215-2.423-.88-5.186-3.54-4.672l-25.505 4.922c-2.396.462-4.435-1.77-3.759-4.114l16.646-57.705c.677-2.35-1.37-4.583-3.769-4.113Z"></path></svg>
\ No newline at end of file
diff --git a/frontend-vanilla/src/api.ts b/frontend-vanilla/src/api.ts
new file mode 100644
index 0000000..c32299d
--- /dev/null
+++ b/frontend-vanilla/src/api.ts
@@ -0,0 +1,29 @@
+export function getCookie(name: string): string | undefined {
+    const value = `; ${document.cookie}`;
+    const parts = value.split(`; ${name}=`);
+    if (parts.length === 2) return parts.pop()?.split(';').shift();
+}
+
+/**
+ * A wrapper around fetch that automatically includes the CSRF token
+ * for state-changing requests (POST, PUT, DELETE).
+ */
+export async function apiFetch(input: RequestInfo | URL, init?: RequestInit): Promise<Response> {
+    const method = init?.method?.toUpperCase() || 'GET';
+    const isStateChanging = ['POST', 'PUT', 'DELETE'].includes(method);
+
+    const headers = new Headers(init?.headers || {});
+
+    if (isStateChanging) {
+        const token = getCookie('csrf_token');
+        if (token) {
+            headers.set('X-CSRF-Token', token);
+        }
+    }
+
+    return fetch(input, {
+        ...init,
+        headers,
+        credentials: 'include', // Ensure cookies are sent
+    });
+}
diff --git a/frontend-vanilla/src/components/FeedItem.test.ts b/frontend-vanilla/src/components/FeedItem.test.ts
new file mode 100644
index 0000000..708a871
--- /dev/null
+++ b/frontend-vanilla/src/components/FeedItem.test.ts
@@ -0,0 +1,23 @@
+import { describe, it, expect } from 'vitest';
+import { createFeedItem } from './FeedItem';
+
+describe('FeedItem Component', () => {
+    const mockFeed = { _id: 1, title: 'My Feed', url: 'http://test', web_url: 'http://test', category: 'tag' };
+
+    it('should render a feed item correctly', () => {
+        const html = createFeedItem(mockFeed, false);
+        expect(html).toContain('My Feed');
+        expect(html).toContain('data-id="1"');
+        expect(html).not.toContain('active');
+    });
+
+    it('should apply active class when isActive is true', () => {
+        const html = createFeedItem(mockFeed, true);
+        expect(html).toContain('active');
+    });
+
+    it('should fallback to URL if title is missing', () => {
+        const html = createFeedItem({ ...mockFeed, title: '' }, false);
+        expect(html).toContain('http://test');
+    });
+});
diff --git a/frontend-vanilla/src/components/FeedItem.ts b/frontend-vanilla/src/components/FeedItem.ts
new file mode 100644
index 0000000..3bf72c2
--- /dev/null
+++ b/frontend-vanilla/src/components/FeedItem.ts
@@ -0,0 +1,11 @@
+import type { Feed } from '../types';
+
+export function createFeedItem(feed: Feed, isActive: boolean): string {
+    return `
+    <li class="feed-item ${isActive ? 'active' : ''}" data-id="${feed._id}">
+      <a href="/v3/feed/${feed._id}" class="feed-link" onclick="event.preventDefault(); window.app.navigate('/feed/${feed._id}')">
+        ${feed.title || feed.url}
+      </a>
+    </li>
+  `;
+}
diff --git a/frontend-vanilla/src/counter.ts b/frontend-vanilla/src/counter.ts
deleted file mode 100644
index 09e5afd..0000000
--- a/frontend-vanilla/src/counter.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-export function setupCounter(element: HTMLButtonElement) {
-  let counter = 0
-  const setCounter = (count: number) => {
-    counter = count
-    element.innerHTML = `count is ${counter}`
-  }
-  element.addEventListener('click', () => setCounter(counter + 1))
-  setCounter(0)
-}
diff --git a/frontend-vanilla/src/main.ts b/frontend-vanilla/src/main.ts
index 6396b50..6846a67 100644
--- a/frontend-vanilla/src/main.ts
+++ b/frontend-vanilla/src/main.ts
@@ -1,24 +1,221 @@
-import './style.css'
-import typescriptLogo from './typescript.svg'
-import viteLogo from '/vite.svg'
-import { setupCounter } from './counter.ts'
-
-document.querySelector<HTMLDivElement>('#app')!.innerHTML = `
-  <div>
-    <a href="https://vite.dev" target="_blank">
-      <img src="${viteLogo}" class="logo" alt="Vite logo" />
-    </a>
-    <a href="https://www.typescriptlang.org/" target="_blank">
-      <img src="${typescriptLogo}" class="logo vanilla" alt="TypeScript logo" />
-    </a>
-    <h1>Vite + TypeScript</h1>
-    <div class="card">
-      <button id="counter" type="button"></button>
-    </div>
-    <p class="read-the-docs">
-      Click on the Vite and TypeScript logos to learn more
-    </p>
+import './style.css';
+import { apiFetch } from './api';
+import { store } from './store';
+import { router } from './router';
+import type { Feed, Item } from './types';
+import { createFeedItem } from './components/FeedItem';
+
+// Cache elements
+const appEl = document.querySelector<HTMLDivElement>('#app')!;
+
+// Initial Layout
+appEl.innerHTML = `
+  <div class="layout">
+    <aside class="sidebar">
+      <div class="sidebar-header">
+        <h2>Neko v3</h2>
+      </div>
+      <ul id="feed-list" class="feed-list"></ul>
+    </aside>
+    <section class="item-list-pane">
+      <header class="top-bar">
+        <h1 id="view-title">All Items</h1>
+      </header>
+      <div id="item-list-container" class="item-list-container"></div>
+    </section>
+    <main class="item-detail-pane">
+      <div id="item-detail-content" class="item-detail-content">
+        <div class="empty-state">Select an item to read</div>
+      </div>
+    </main>
   </div>
-`
+`;
+
+const feedListEl = document.getElementById('feed-list')!;
+const viewTitleEl = document.getElementById('view-title')!;
+const itemListEl = document.getElementById('item-list-container')!;
+const itemDetailEl = document.getElementById('item-detail-content')!;
+
+// --- Rendering Functions ---
+
+function renderFeeds() {
+  const { feeds, activeFeedId } = store;
+  feedListEl.innerHTML = feeds.map((feed: Feed) =>
+    createFeedItem(feed, feed._id === activeFeedId)
+  ).join('');
+}
+
+function renderItems() {
+  const { items, loading } = store;
+
+  if (loading) {
+    itemListEl.innerHTML = '<p class="loading">Loading items...</p>';
+    return;
+  }
+
+  if (items.length === 0) {
+    itemListEl.innerHTML = '<p class="empty">No items found.</p>';
+    return;
+  }
+
+  itemListEl.innerHTML = `
+    <ul class="item-list">
+      ${items.map((item: Item) => `
+        <li class="item-row ${item.read ? 'read' : ''}" data-id="${item._id}">
+          <div class="item-title">${item.title}</div>
+          <div class="item-meta">${item.feed_title || ''}</div>
+        </li>
+      `).join('')}
+    </ul>
+  `;
+
+  // Add click listeners to items
+  itemListEl.querySelectorAll('.item-row').forEach(row => {
+    row.addEventListener('click', () => {
+      const id = parseInt(row.getAttribute('data-id') || '0');
+      selectItem(id);
+    });
+  });
+}
+
+async function selectItem(id: number) {
+  const item = store.items.find((i: Item) => i._id === id);
+  if (!item) return;
+
+  // Mark active row
+  itemListEl.querySelectorAll('.item-row').forEach(row => {
+    row.classList.toggle('active', parseInt(row.getAttribute('data-id') || '0') === id);
+  });
+
+  // Render basic detail
+  itemDetailEl.innerHTML = `
+    <article class="item-detail">
+      <header>
+        <h1><a href="${item.url}" target="_blank">${item.title}</a></h1>
+        <div class="item-meta">
+          From ${item.feed_title || 'Unknown'} on ${new Date(item.publish_date).toLocaleString()}
+        </div>
+      </header>
+      <div id="full-content" class="full-content">
+        ${item.description || 'No description available.'}
+      </div>
+    </article>
+  `;
+
+  // Mark as read if not already
+  if (!item.read) {
+    try {
+      await apiFetch(`/api/item/${item._id}`, {
+        method: 'PUT',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ read: true })
+      });
+      item.read = true;
+      const row = itemListEl.querySelector(`.item-row[data-id="${id}"]`);
+      if (row) row.classList.add('read');
+    } catch (err) {
+      console.error('Failed to mark as read', err);
+    }
+  }
+
+  // Fetch full content if missing
+  if (item.url && (!item.full_content || item.full_content === item.description)) {
+    try {
+      const res = await apiFetch(`/api/item/${item._id}/content`);
+      if (res.ok) {
+        const data = await res.json();
+        if (data.full_content) {
+          item.full_content = data.full_content;
+          const contentEl = document.getElementById('full-content');
+          if (contentEl) contentEl.innerHTML = data.full_content;
+        }
+      }
+    } catch (err) {
+      console.error('Failed to fetch full content', err);
+    }
+  }
+}
+
+// --- Data Actions ---
+
+async function fetchFeeds() {
+  try {
+    const res = await apiFetch('/api/feed/');
+    if (!res.ok) throw new Error('Failed to fetch feeds');
+    const feeds = await res.json();
+    store.setFeeds(feeds);
+  } catch (err) {
+    console.error(err);
+  }
+}
+
+async function fetchItems(feedId?: string, tagName?: string) {
+  store.setLoading(true);
+  try {
+    let url = '/api/stream';
+    const params = new URLSearchParams();
+    if (feedId) params.append('feed_id', feedId);
+    if (tagName) params.append('tag', tagName);
+
+    const res = await apiFetch(`${url}?${params.toString()}`);
+    if (!res.ok) throw new Error('Failed to fetch items');
+    const items = await res.json();
+    store.setItems(items);
+    itemDetailEl.innerHTML = '<div class="empty-state">Select an item to read</div>';
+  } catch (err) {
+    console.error(err);
+    store.setItems([]);
+  } finally {
+    store.setLoading(false);
+  }
+}
+
+// --- App Logic ---
+
+function handleRoute() {
+  const route = router.getCurrentRoute();
+
+  if (route.path === '/feed' && route.params.feedId) {
+    const id = parseInt(route.params.feedId);
+    store.setActiveFeed(id);
+    const feed = store.feeds.find((f: Feed) => f._id === id);
+    viewTitleEl.textContent = feed ? feed.title : `Feed ${id}`;
+    fetchItems(route.params.feedId);
+  } else if (route.path === '/tag' && route.params.tagName) {
+    store.setActiveFeed(null);
+    viewTitleEl.textContent = `Tag: ${route.params.tagName}`;
+    fetchItems(undefined, route.params.tagName);
+  } else {
+    store.setActiveFeed(null);
+    viewTitleEl.textContent = 'All Items';
+    fetchItems();
+  }
+}
+
+// Subscribe to store
+store.on('feeds-updated', renderFeeds);
+store.on('active-feed-updated', renderFeeds);
+store.on('items-updated', renderItems);
+store.on('loading-state-changed', renderItems);
+
+// Subscribe to router
+router.addEventListener('route-changed', handleRoute);
+
+// Global app object for inline handlers
+(window as any).app = {
+  navigate: (path: string) => router.navigate(path)
+};
+
+// Start
+async function init() {
+  const authRes = await apiFetch('/api/auth');
+  if (authRes.status === 401) {
+    window.location.href = '/login/';
+    return;
+  }
+
+  await fetchFeeds();
+  handleRoute(); // handles initial route
+}
 
-setupCounter(document.querySelector<HTMLButtonElement>('#counter')!)
+init();
diff --git a/frontend-vanilla/src/router.ts b/frontend-vanilla/src/router.ts
new file mode 100644
index 0000000..08a9e02
--- /dev/null
+++ b/frontend-vanilla/src/router.ts
@@ -0,0 +1,40 @@
+export type Route = {
+    path: string;
+    params: Record<string, string>;
+};
+
+export class Router extends EventTarget {
+    constructor() {
+        super();
+        window.addEventListener('popstate', () => this.handleRouteChange());
+    }
+
+    private handleRouteChange() {
+        this.dispatchEvent(new CustomEvent('route-changed', { detail: this.getCurrentRoute() }));
+    }
+
+    getCurrentRoute(): Route {
+        const path = window.location.pathname.replace(/^\/v3\//, '');
+        const segments = path.split('/').filter(Boolean);
+
+        let routePath = '/';
+        const params: Record<string, string> = {};
+
+        if (segments[0] === 'feed' && segments[1]) {
+            routePath = '/feed';
+            params.feedId = segments[1];
+        } else if (segments[0] === 'tag' && segments[1]) {
+            routePath = '/tag';
+            params.tagName = segments[1];
+        }
+
+        return { path: routePath, params };
+    }
+
+    navigate(path: string) {
+        window.history.pushState({}, '', `/v3${path}`);
+        this.handleRouteChange();
+    }
+}
+
+export const router = new Router();
diff --git a/frontend-vanilla/src/setupTests.ts b/frontend-vanilla/src/setupTests.ts
new file mode 100644
index 0000000..7b0828b
--- /dev/null
+++ b/frontend-vanilla/src/setupTests.ts
@@ -0,0 +1 @@
+import '@testing-library/jest-dom';
diff --git a/frontend-vanilla/src/store.test.ts b/frontend-vanilla/src/store.test.ts
new file mode 100644
index 0000000..688e43e
--- /dev/null
+++ b/frontend-vanilla/src/store.test.ts
@@ -0,0 +1,48 @@
+import { describe, it, expect, vi } from 'vitest';
+import { Store } from './store';
+
+describe('Store', () => {
+    it('should store and notify about feeds', () => {
+        const store = new Store();
+        const mockFeeds = [
+            { _id: 1, title: 'Feed 1', url: 'http://1', web_url: 'http://1', category: 'cat' }
+        ];
+
+        const callback = vi.fn();
+        store.addEventListener('feeds-updated', callback);
+
+        store.setFeeds(mockFeeds);
+
+        expect(store.feeds).toEqual(mockFeeds);
+        expect(callback).toHaveBeenCalled();
+    });
+
+    it('should handle items and loading state', () => {
+        const store = new Store();
+        const mockItems = [{ _id: 1, title: 'Item 1' } as any];
+
+        const itemCallback = vi.fn();
+        const loadingCallback = vi.fn();
+
+        store.addEventListener('items-updated', itemCallback);
+        store.addEventListener('loading-state-changed', loadingCallback);
+
+        store.setLoading(true);
+        expect(store.loading).toBe(true);
+        expect(loadingCallback).toHaveBeenCalled();
+
+        store.setItems(mockItems);
+        expect(store.items).toEqual(mockItems);
+        expect(itemCallback).toHaveBeenCalled();
+    });
+
+    it('should notify when active feed changes', () => {
+        const store = new Store();
+        const callback = vi.fn();
+        store.addEventListener('active-feed-updated', callback);
+
+        store.setActiveFeed(123);
+        expect(store.activeFeedId).toBe(123);
+        expect(callback).toHaveBeenCalled();
+    });
+});
diff --git a/frontend-vanilla/src/store.ts b/frontend-vanilla/src/store.ts
new file mode 100644
index 0000000..d274c5d
--- /dev/null
+++ b/frontend-vanilla/src/store.ts
@@ -0,0 +1,41 @@
+import type { Feed, Item } from './types.ts';
+
+export type StoreEvent = 'feeds-updated' | 'items-updated' | 'active-feed-updated' | 'loading-state-changed';
+
+export class Store extends EventTarget {
+    feeds: Feed[] = [];
+    items: Item[] = [];
+    activeFeedId: number | null = null;
+    loading: boolean = false;
+
+    setFeeds(feeds: Feed[]) {
+        this.feeds = feeds;
+        this.emit('feeds-updated');
+    }
+
+    setItems(items: Item[]) {
+        this.items = items;
+        this.emit('items-updated');
+    }
+
+    setActiveFeed(id: number | null) {
+        this.activeFeedId = id;
+        this.emit('active-feed-updated');
+    }
+
+    setLoading(loading: boolean) {
+        this.loading = loading;
+        this.emit('loading-state-changed');
+    }
+
+    private emit(type: StoreEvent, detail?: any) {
+        this.dispatchEvent(new CustomEvent(type, { detail }));
+    }
+
+    // Helper to add typed listeners
+    on(type: StoreEvent, callback: (e: CustomEvent) => void) {
+        this.addEventListener(type, callback as EventListener);
+    }
+}
+
+export const store = new Store();
diff --git a/frontend-vanilla/src/style.css b/frontend-vanilla/src/style.css
index 3bcdbd0..a9c1c61 100644
--- a/frontend-vanilla/src/style.css
+++ b/frontend-vanilla/src/style.css
@@ -1,96 +1,210 @@
 :root {
-  font-family: system-ui, Avenir, Helvetica, Arial, sans-serif;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
   line-height: 1.5;
   font-weight: 400;
 
   color-scheme: light dark;
-  color: rgba(255, 255, 255, 0.87);
-  background-color: #242424;
+  --bg-color: #ffffff;
+  --text-color: #213547;
+  --sidebar-bg: #f8f9fa;
+  --border-color: #e9ecef;
+  --accent-color: #007bff;
+  --hover-color: #e2e6ea;
+  --sidebar-width: 250px;
+  --item-list-width: 350px;
+}
 
-  font-synthesis: none;
-  text-rendering: optimizeLegibility;
-  -webkit-font-smoothing: antialiased;
-  -moz-osx-font-smoothing: grayscale;
+@media (prefers-color-scheme: dark) {
+  :root {
+    --bg-color: #1a1a1a;
+    --text-color: #e9ecef;
+    --sidebar-bg: #2d2d2d;
+    --border-color: #444;
+    --accent-color: #375a7f;
+    --hover-color: #3e3e3e;
+  }
 }
 
-a {
-  font-weight: 500;
-  color: #646cff;
-  text-decoration: inherit;
+body {
+  margin: 0;
+  color: var(--text-color);
+  background-color: var(--bg-color);
+  height: 100vh;
+  overflow: hidden;
 }
-a:hover {
-  color: #535bf2;
+
+#app {
+  height: 100%;
 }
 
-body {
+.layout {
+  display: flex;
+  height: 100%;
+}
+
+/* Sidebar */
+.sidebar {
+  width: var(--sidebar-width);
+  background-color: var(--sidebar-bg);
+  border-right: 1px solid var(--border-color);
+  display: flex;
+  flex-direction: column;
+}
+
+.sidebar-header {
+  padding: 1rem;
+  border-bottom: 1px solid var(--border-color);
+}
+
+.sidebar-header h2 {
   margin: 0;
+  font-size: 1.1rem;
+}
+
+.feed-list {
+  list-style: none;
+  padding: 0;
+  margin: 0;
+  overflow-y: auto;
+  flex: 1;
+}
+
+.feed-link {
+  display: block;
+  padding: 0.5rem 1rem;
+  text-decoration: none;
+  color: var(--text-color);
+  font-size: 0.9rem;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+.feed-item:hover {
+  background-color: var(--hover-color);
+}
+
+.feed-item.active {
+  background-color: var(--hover-color);
+  font-weight: bold;
+}
+
+/* Item List Pane */
+.item-list-pane {
+  width: var(--item-list-width);
+  border-right: 1px solid var(--border-color);
   display: flex;
-  place-items: center;
-  min-width: 320px;
-  min-height: 100vh;
+  flex-direction: column;
+  background-color: var(--bg-color);
 }
 
-h1 {
-  font-size: 3.2em;
-  line-height: 1.1;
+.top-bar {
+  padding: 0.75rem 1rem;
+  border-bottom: 1px solid var(--border-color);
 }
 
-#app {
-  max-width: 1280px;
-  margin: 0 auto;
-  padding: 2rem;
-  text-align: center;
+.top-bar h1 {
+  margin: 0;
+  font-size: 1rem;
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
 }
 
-.logo {
-  height: 6em;
-  padding: 1.5em;
-  will-change: filter;
-  transition: filter 300ms;
+.item-list-container {
+  flex: 1;
+  overflow-y: auto;
 }
-.logo:hover {
-  filter: drop-shadow(0 0 2em #646cffaa);
+
+.item-list {
+  list-style: none;
+  padding: 0;
+  margin: 0;
+}
+
+.item-row {
+  padding: 0.75rem 1rem;
+  border-bottom: 1px solid var(--border-color);
+  cursor: pointer;
+  transition: background 0.1s;
+}
+
+.item-row:hover {
+  background-color: var(--hover-color);
+}
+
+.item-row.active {
+  background-color: var(--hover-color);
+  border-left: 3px solid var(--accent-color);
 }
-.logo.vanilla:hover {
-  filter: drop-shadow(0 0 2em #3178c6aa);
+
+.item-row.read {
+  opacity: 0.6;
 }
 
-.card {
-  padding: 2em;
+.item-title {
+  font-weight: 600;
+  font-size: 0.95rem;
+  margin-bottom: 0.2rem;
+  line-height: 1.3;
 }
 
-.read-the-docs {
+.item-meta {
+  font-size: 0.8rem;
   color: #888;
 }
 
-button {
-  border-radius: 8px;
-  border: 1px solid transparent;
-  padding: 0.6em 1.2em;
-  font-size: 1em;
-  font-weight: 500;
-  font-family: inherit;
-  background-color: #1a1a1a;
-  cursor: pointer;
-  transition: border-color 0.25s;
+/* Item Detail Pane */
+.item-detail-pane {
+  flex: 1;
+  overflow-y: auto;
+  background-color: var(--bg-color);
 }
-button:hover {
-  border-color: #646cff;
+
+.item-detail-content {
+  max-width: 800px;
+  margin: 0 auto;
+  padding: 2rem;
 }
-button:focus,
-button:focus-visible {
-  outline: 4px auto -webkit-focus-ring-color;
+
+.item-detail header {
+  margin-bottom: 2rem;
+  border-bottom: 1px solid var(--border-color);
+  padding-bottom: 1rem;
 }
 
-@media (prefers-color-scheme: light) {
-  :root {
-    color: #213547;
-    background-color: #ffffff;
-  }
-  a:hover {
-    color: #747bff;
-  }
-  button {
-    background-color: #f9f9f9;
-  }
+.item-detail h1 {
+  font-size: 1.8rem;
+  margin: 0 0 0.5rem 0;
+}
+
+.item-detail h1 a {
+  color: var(--text-color);
+  text-decoration: none;
+}
+
+.full-content {
+  font-size: 1.1rem;
+  line-height: 1.6;
+}
+
+.full-content img {
+  max-width: 100%;
+  height: auto;
+}
+
+.empty-state {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  height: 100%;
+  color: #888;
+  font-size: 1.2rem;
 }
+
+.loading,
+.empty {
+  padding: 1rem;
+  text-align: center;
+  color: #888;
+}
\ No newline at end of file
diff --git a/frontend-vanilla/src/types.ts b/frontend-vanilla/src/types.ts
new file mode 100644
index 0000000..4c1110f
--- /dev/null
+++ b/frontend-vanilla/src/types.ts
@@ -0,0 +1,24 @@
+export interface Feed {
+    _id: number;
+    url: string;
+    web_url: string;
+    title: string;
+    category: string;
+}
+
+export interface Item {
+    _id: number;
+    feed_id: number;
+    title: string;
+    url: string;
+    description: string;
+    publish_date: string;
+    read: boolean;
+    starred: boolean;
+    full_content?: string;
+    header_image?: string;
+    feed_title?: string;
+}
+export interface Category {
+    title: string;
+}
diff --git a/frontend-vanilla/src/typescript.svg b/frontend-vanilla/src/typescript.svg
deleted file mode 100644
index d91c910..0000000
--- a/frontend-vanilla/src/typescript.svg
+++ /dev/null
@@ -1 +0,0 @@
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diff --git a/frontend-vanilla/vitest.config.ts b/frontend-vanilla/vitest.config.ts
new file mode 100644
index 0000000..9695d57
--- /dev/null
+++ b/frontend-vanilla/vitest.config.ts
@@ -0,0 +1,10 @@
+/// <reference types="vitest" />
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+    test: {
+        environment: 'jsdom',
+        globals: true,
+        setupFiles: ['./src/setupTests.ts'],
+    },
+});