diff --git a/.github/workflows/content-rules-checks.yml b/.github/workflows/content-rules-checks.yml
new file mode 100644
index 0000000..37ff04a
--- /dev/null
+++ b/.github/workflows/content-rules-checks.yml
@@ -0,0 +1,36 @@
+name: Content Rules Checks
+
+on:
+  pull_request:
+    branches: ["main"]
+    paths:
+      - "history.md"
+      - "_research/index.md"
+      - "CLAUDE.md"
+      - "README.md"
+      - "scripts/validate-content-rules.sh"
+    paths-ignore:
+      - ".*/**/*.md"
+      - "**/.*/**/*.md"
+  push:
+    branches: ["main"]
+    paths:
+      - "history.md"
+      - "_research/index.md"
+      - "CLAUDE.md"
+      - "README.md"
+      - "scripts/validate-content-rules.sh"
+    paths-ignore:
+      - ".*/**/*.md"
+      - "**/.*/**/*.md"
+
+jobs:
+  content-rules:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Validate history and research content rules
+        run: bash scripts/validate-content-rules.sh
diff --git a/.github/workflows/teaching-content-checks.yml b/.github/workflows/teaching-content-checks.yml
new file mode 100644
index 0000000..52cc39a
--- /dev/null
+++ b/.github/workflows/teaching-content-checks.yml
@@ -0,0 +1,42 @@
+name: Teaching Content Checks
+
+on:
+  pull_request:
+    branches: ["main"]
+    paths:
+      - "_teaching/**/*.md"
+      - ".markdownlint-cli2.jsonc"
+      - ".prettierrc.json"
+      - "package.json"
+      - "package-lock.json"
+  push:
+    branches: ["main"]
+    paths:
+      - "_teaching/**/*.md"
+      - ".markdownlint-cli2.jsonc"
+      - ".prettierrc.json"
+      - "package.json"
+      - "package-lock.json"
+
+jobs:
+  markdown-quality:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: "20"
+          cache: "npm"
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run markdownlint for teaching content
+        run: npx markdownlint-cli2 --config .markdownlint-cli2.jsonc "_teaching/**/*.md"
+
+      - name: Check prettier formatting for teaching content
+        run: npx prettier --check "_teaching/**/*.md"
diff --git a/.opencode/commands/add-news.md b/.opencode/commands/add-news.md
index f90a08b..2cbc08e 100644
--- a/.opencode/commands/add-news.md
+++ b/.opencode/commands/add-news.md
@@ -11,7 +11,7 @@ Follow these steps:
    - Years are organized with `## Year` headings (e.g., `## 2026`, `## 2025`)
    - Years are sorted descending (newest first)
    - Create year section if it doesn't exist
-   - Months within a year are in chronological order (January at top)
+   - Months within a year are in reverse chronological order (December at top)
    - Format: `- [news content]`
 5. Add the same item to News.md:
    - Years are organized with `## Year` headings
diff --git a/.opencode/commands/add-paper.md b/.opencode/commands/add-paper.md
index 244dbf5..df76730 100644
--- a/.opencode/commands/add-paper.md
+++ b/.opencode/commands/add-paper.md
@@ -150,7 +150,7 @@ Output (for paper [18]):
 ```markdown
 <h3 id="18">[18] Bashkatov, A., Bürkle, F., Demirkır, Ç., Ding, W., <strong>Sanjay, V.</strong>, Babich, A., Yang, X., Mutschke, G., Czarske, J., Lohse, D., Krug, D., Büttner, L., & Eckert, K. Electrolyte droplet spraying in H2 bubbles during water electrolysis. Nat. Commun., 16, 4580 (2025).</h3>
 
-<tags><span>Bubbles</span><span>Jets</span></tags>
+<div class="tags"><span>Bubbles</span><span>Jets</span></div>
 
 [![Nat. Commun.](https://img.shields.io/static/v1.svg?style=flat-square&label=Nat.%20Commun.&message=OA&color=orange)](https://doi.org/10.1038/s41467-025-59762-7)
 [![Blog](https://img.shields.io/badge/Blog-Coming%20Soon-yellow?style=flat-square&logo=obsidian&logoColor=white)](https://blogs.comphy-lab.org/0_ToDo-Blog-public)
diff --git a/CLAUDE.md b/CLAUDE.md
index 3984a61..2d75004 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -30,7 +30,7 @@ The website implements a sophisticated command palette system that requires coor
 - Client-side JavaScript filtering with SEO-friendly static pages
 - Pre-generated tag pages that redirect to filtered views
 - Multiple URL variations for better SEO coverage
-- Tags must be added to `_research/index.md` using `<tags><span>TagName</span></tags>` format
+- Tags must be added to `_research/index.md` using `<div class="tags"><span>TagName</span></div>` format
 
 ## Essential Commands
 
@@ -68,7 +68,7 @@ Add to `_research/index.md` with this exact format:
 ```markdown
 <h3 id="NUMBER">[NUMBER] Author1, A., **Author2, B.**, & Author3, C. Title. _Journal_, Volume, Pages (Year).</h3>
 
-<tags><span>Tag1</span><span>Tag2</span><span>Featured</span></tags>
+<div class="tags"><span>Tag1</span><span>Tag2</span><span>Featured</span></div>
 
 [![Badge](https://img.shields.io/static/v1.svg?style=flat-square&label=LABEL&message=MESSAGE&color=COLOR)](URL)
 ```
diff --git a/README.md b/README.md
index c596134..55e6720 100644
--- a/README.md
+++ b/README.md
@@ -227,7 +227,7 @@ A static website for the Computational Multiphase Physics Laboratory, built with
 ```markdown
 <h3 id="NUMBER">[NUMBER] Author1, A., **Author2, B.**, & Author3, C. Title. _Journal_, Volume, Pages (Year).</h3>
 
-<tags><span>Tag1</span><span>Tag2</span><span>Featured</span></tags>
+<div class="tags"><span>Tag1</span><span>Tag2</span><span>Featured</span></div>
 
 [![Badge1](https://img.shields.io/static/v1.svg?style=flat-square&label=LABEL&message=MESSAGE&color=COLOR)](URL)
 [![Badge2](https://img.shields.io/static/v1.svg?style=flat-square&label=LABEL&message=MESSAGE&color=COLOR)](URL)
@@ -429,7 +429,7 @@ The search functionality includes content from our external blog at blogs.comphy
 Research papers can be tagged with multiple topics. Tags are defined in the markdown files using the following format:
 
 ```html
-<tags><span>Tag1</span><span>Tag2</span></tags>
+<div class="tags"><span>Tag1</span><span>Tag2</span></div>
 ```
 
 These tags are:
diff --git a/_layouts/history.html b/_layouts/history.html
index 6de682b..b9f13fb 100644
--- a/_layouts/history.html
+++ b/_layouts/history.html
@@ -80,6 +80,7 @@
   </script>
 
   <!-- JavaScript dependencies -->
+  <script defer src="/assets/js/utils.js"></script>
   <script defer src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
   <script defer src="https://cdn.jsdelivr.net/npm/fuse.js@6.6.2"></script>
   <script defer src="/assets/js/main.js"></script>
@@ -314,4 +315,4 @@
   </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/_layouts/research.html b/_layouts/research.html
index 62a0932..2d93833 100644
--- a/_layouts/research.html
+++ b/_layouts/research.html
@@ -62,6 +62,9 @@
   }
   </script>
 
+  <!-- Core utilities (must load first) -->
+  <script defer src="/assets/js/utils.js"></script>
+
   <!-- Command palette (implementation in assets/js/command-palette.js) -->
   <script defer src="/assets/js/command-palette.js"></script>
 
@@ -274,12 +277,6 @@ <h3>Contents</h3>
     </footer>
   </div>
 
-  <!-- Core scripts -->
-  <script defer src="/assets/js/main.js"></script>
-  <script defer src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
-  <!-- Search dependencies -->
-  <script defer src="https://cdn.jsdelivr.net/npm/fuse.js@6.6.2"></script>
-
   <script>
     document.addEventListener('DOMContentLoaded', function() {
       // Generate table of contents
@@ -419,7 +416,7 @@ <h3>Contents</h3>
         }
 
         // Handle tag filtering
-        const allTags = document.querySelectorAll('tags span');
+        const allTags = document.querySelectorAll('.tags span');
         const paperContainers = document.querySelectorAll('.paper-container');
         let activeTag = null;
 
@@ -429,7 +426,7 @@ <h3>Contents</h3>
 
         // Function to highlight matching tags
         const updateMatchingTags = (tagText, shouldHighlight) => {
-          document.querySelectorAll('tags span').forEach(tag => {
+          document.querySelectorAll('.tags span').forEach(tag => {
             if (tag.textContent === tagText) {
               // First remove any active class
               tag.classList.remove('active');
@@ -470,7 +467,7 @@ <h3>Contents</h3>
 
             // Filter papers
             paperContainers.forEach(container => {
-              const containerTags = container.querySelector('tags');
+              const containerTags = container.querySelector('.tags');
               if (containerTags && containerTags.textContent.includes(tagText)) {
                 container.classList.remove('hidden');
               } else {
@@ -519,4 +516,4 @@ <h3>Contents</h3>
 
   <!-- Command palette functionality is now implemented in command-palette.js -->
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/_layouts/teaching.html b/_layouts/teaching.html
index 6aac77c..272a8c4 100644
--- a/_layouts/teaching.html
+++ b/_layouts/teaching.html
@@ -79,6 +79,7 @@
   </script>
 
   <!-- JavaScript dependencies -->
+  <script defer src="/assets/js/utils.js"></script>
   <script defer src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
   <script defer src="https://cdn.jsdelivr.net/npm/fuse.js@6.6.2"></script>
   <script defer src="/assets/js/main.js"></script>
@@ -129,8 +130,6 @@
     })();
   </script>
 
-  <script defer src="/assets/js/command-palette.js"></script>
-
   <script>
     // Check if we're on localhost
     if (window.location.hostname === 'localhost' || window.location.hostname === '127.0.0.1') {
@@ -318,4 +317,4 @@
   </script>
 
 </body>
-</html>
\ No newline at end of file
+</html>
diff --git a/_layouts/team.html b/_layouts/team.html
index d6fd315..5863052 100644
--- a/_layouts/team.html
+++ b/_layouts/team.html
@@ -398,12 +398,6 @@ <h2 class="map-heading">Team, collaborators, and Conference visits</h2>
       </div> <!-- end ss-go-top -->
     </footer>
 
-  <!-- Core scripts -->
-  <script defer src="/assets/js/main.js"></script>
-  <script defer src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
-  <!-- Search dependencies -->
-  <script defer src="https://cdn.jsdelivr.net/npm/fuse.js@6.6.2"></script>
-
   <script>
     document.addEventListener('DOMContentLoaded', () => {
       // Add IDs to all h2 headings that don't have them
diff --git a/_research/index.md b/_research/index.md
index ff28f2c..fa20038 100644
--- a/_research/index.md
+++ b/_research/index.md
@@ -7,23 +7,23 @@ title: Research
 
 ## Sort by topic
 
-<tags><span>Bubbles</span></tags>
-<tags><span>Drops</span></tags>
-<tags><span>Jets</span></tags>
-<tags><span>Sheets</span></tags>
-<tags><span>Non-Newtonian</span></tags>
-<tags><span>Coalescence</span></tags>
-<tags><span>Superamphiphobic-surfaces</span></tags>
-<tags><span>Impact forces</span></tags>
-<tags><span>Dissipative anomaly</span></tags>
-<tags><span>Soft-matter-singularities</span></tags>
-<tags><span>Elastic beads</span></tags>
-<tags><span>Bouncing</span></tags>
-<tags><span>Rupture</span></tags>
-<tags><span>Contact line</span></tags>
-<tags><span>Marangoni flows</span></tags>
-<tags><span>Numerical methods</span></tags>
-<tags><span>Featured</span></tags>
+<div class="tags"><span>Bubbles</span></div>
+<div class="tags"><span>Drops</span></div>
+<div class="tags"><span>Jets</span></div>
+<div class="tags"><span>Sheets</span></div>
+<div class="tags"><span>Non-Newtonian</span></div>
+<div class="tags"><span>Coalescence</span></div>
+<div class="tags"><span>Superamphiphobic-surfaces</span></div>
+<div class="tags"><span>Impact forces</span></div>
+<div class="tags"><span>Dissipative anomaly</span></div>
+<div class="tags"><span>Soft-matter-singularities</span></div>
+<div class="tags"><span>Elastic beads</span></div>
+<div class="tags"><span>Bouncing</span></div>
+<div class="tags"><span>Rupture</span></div>
+<div class="tags"><span>Contact line</span></div>
+<div class="tags"><span>Marangoni flows</span></div>
+<div class="tags"><span>Numerical methods</span></div>
+<div class="tags"><span>Featured</span></div>
 
 > Click on any tag to filter papers by topic. Each paper can have multiple tags.
 
@@ -31,7 +31,7 @@ title: Research
 
 ### <strong>Dixit, A. K.</strong>, Zhao, C., Zaleski, S., Lohse, D., & <strong>Sanjay, V.</strong> Holey sheets: Double-Threshold Rupture of Draining Liquid Films. arXiv preprint arXiv:2509.12789 (2025).
 
-<tags><span>Sheets</span><span>Rupture</span><span>Soft-matter-singularities</span><span>Featured</span></tags>
+<div class="tags"><span>Sheets</span><span>Rupture</span><span>Soft-matter-singularities</span><span>Featured</span></div>
 
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2509.12789&color=green)](https://arxiv.org/abs/2509.12789)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/HoleySheet)
@@ -41,7 +41,7 @@ title: Research
 
 ### <strong>Jana, S.</strong>, Kolinski, J., Lohse, D., & <strong>Sanjay, V.</strong> Impacting spheres: from liquid drops to elastic beads. arXiv preprint arXiv:2510.24855 (2025).
 
-<tags><span>Drops</span><span>Impact forces</span><span>Elastic beads</span></tags>
+<div class="tags"><span>Drops</span><span>Impact forces</span><span>Elastic beads</span></div>
 
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2510.24855&color=green)](https://arxiv.org/abs/2510.24855)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/Soft-Sphere-Impacts)
@@ -49,7 +49,7 @@ title: Research
 
 ### Appleford, T., <strong>Sanjay, V.</strong>, Jalaal, M. On the Rheology of Two-Dimensional Dilute Emulsions. arXiv preprint arXiv:2508.13022 (2025).
 
-<tags><span>Emulsions</span><span>Rheology</span></tags>
+<div class="tags"><span>Emulsions</span><span>Rheology</span></div>
 
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2508.13022&color=green)](https://arxiv.org/abs/2508.13022)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/tappleford/droplet_under_shear_newtonian_2D)
@@ -57,7 +57,7 @@ title: Research
 
 ### Verschuur, C. I., Oratis, A. T., <strong>Sanjay, V.</strong>, & Snoeijer, J. H. How elasticity affects bubble pinch-off. arXiv preprint arXiv:2511.20075 (2025).
 
-<tags><span>Bubbles</span><span>Soft-matter-singularities</span><span>Elastic beads</span></tags>
+<div class="tags"><span>Bubbles</span><span>Soft-matter-singularities</span><span>Elastic beads</span></div>
 
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2511.20075&color=green)](https://arxiv.org/abs/2511.20075)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/ElasticPinchOff/)
@@ -65,7 +65,7 @@ title: Research
 
 ### Ghaemi, A. H., Yang, Z., Huang, A., <strong>Sanjay, V.</strong>, Feng, J., & Constante-Amores, C. R. Bursting bubbles in Herschel-Bulkley fluids: dynamics and jetting transitions. arXiv preprint arXiv:2511.23345 (2025).
 
-<tags><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span></tags>
+<div class="tags"><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span></div>
 
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2511.23345&color=green)](https://arxiv.org/abs/2511.23345)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/BurstingBubble_Herschel-Bulkley/)
@@ -75,7 +75,7 @@ title: Research
 
 <h3 id="21">[21] Díaz, D., <strong>Bhargava, A. S.</strong>, Walz, F., Sharifi, A., Summaly, S., Berger, R., Kappl, M., Butt, H.-J., Lohse, D., Willers, T., <strong>Sanjay, V.</strong>, & Vollmer, D. Stood-up Drop to Determine Receding Contact Angles. Soft Matter, 22, 657-667 (2026).</h3>
 
-<tags><span>Drops</span><span>Contact line</span></tags>
+<div class="tags"><span>Drops</span><span>Contact line</span></div>
 
 [![Soft Matter](https://img.shields.io/static/v1.svg?style=flat-square&label=Soft%20Matter&message=OA&color=orange)](https://doi.org/10.1039/D5SM00985E)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2511.20259&color=green)](https://arxiv.org/abs/2511.20259)
@@ -86,7 +86,7 @@ title: Research
 
 <h3 id="20">[20] Demirkır, Ç., Yang, R., Bashkatov, A., <strong>Sanjay, V.</strong>, Lohse, D., & Krug, D. To jump or not to jump: Adhesion and viscous dissipation dictate the detachment of coalescing wall-attached bubbles. Phys. Rev. Fluids, 10, 123602 (2025).</h3>
 
-<tags><span>Bubbles</span><span>Coalescence</span></tags>
+<div class="tags"><span>Bubbles</span><span>Coalescence</span></div>
 
 [![PRF](https://img.shields.io/static/v1.svg?style=flat-square&label=PRF&message=OA&color=orange)](https://doi.org/10.1103/nq3w-57gg)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2501.05532&color=green)](https://arxiv.org/abs/2501.05532)
@@ -97,7 +97,7 @@ title: Research
 
 <h3 id="19">[19] Mclauchlan, J., Walker, J. S., <strong>Sanjay, V.</strong>, Jalaal, M., Reid, J. P., Squires, A. M., & Souslov, A. Bouncing microdroplets on hydrophobic surfaces. Proc. Natl. Acad. Sci., 122, e2507309122 (2025).</h3>
 
-<tags><span>Drops</span><span>Bouncing</span></tags>
+<div class="tags"><span>Drops</span><span>Bouncing</span></div>
 
 [![PNAS](https://img.shields.io/static/v1.svg?style=flat-square&label=PNAS&message=OA&color=orange)](https://doi.org/10.1073/pnas.2507309122)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2503.22527&color=green)](https://arxiv.org/abs/2503.22527)
@@ -105,7 +105,7 @@ title: Research
 
 <h3 id="18">[18] Saini, M., <strong>Sanjay, V.</strong>, Saade, Y., Lohse, D., & Popinet, S. Implementation of integral surface tension formulations in a volume of fluid framework and their applications to Marangoni flows. J. Comput. Phys., 542, 114348 (2025).</h3>
 
-<tags><span>Marangoni flows</span><span>Numerical methods</span></tags>
+<div class="tags"><span>Marangoni flows</span><span>Numerical methods</span></div>
 
 [![J. Comput. Phys.](https://img.shields.io/static/v1.svg?style=flat-square&label=J.%20Comput.%20Phys.&message=OA&color=orange)](https://doi.org/10.1016/j.jcp.2025.114348)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/marangoniSheet)
@@ -113,7 +113,7 @@ title: Research
 
 <h3 id="17">[17] Bashkatov, A., Bürkle, F., Demirkır, Ç., Ding, W., <strong>Sanjay, V.</strong>, Babich, A., Yang, X., Mutschke, G., Czarske, J., Lohse, D., Krug, D., Lars, B., & Eckert, E. Electrolyte droplet spraying in H2 bubbles during water electrolysis under normal and microgravity conditions. Nat. Commun., 16, 4580 (2025).</h3>
 
-<tags><span>Bubbles</span><span>Jets</span><span>Coalescence</span><span>Soft-matter-singularities</span><span>Drops</span></tags>
+<div class="tags"><span>Bubbles</span><span>Jets</span><span>Coalescence</span><span>Soft-matter-singularities</span><span>Drops</span></div>
 
 [![Nat. Commun.](https://img.shields.io/static/v1.svg?style=flat-square&label=Nat.%20Commun.&message=OA&color=orange)](https://doi.org/10.1038/s41467-025-59762-7)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2409.00515&color=green)](https://arxiv.org/abs/2409.00515)
@@ -124,7 +124,7 @@ title: Research
 
 <h3 id="16">[16] <strong>Dixit, A.</strong>, Oratis, A., Zinelis, K., Lohse, D., & <strong>Sanjay, V.</strong> Viscoelastic Worthington Jets and Droplets Produced by Bursting Bubbles. J. Fluid Mech., 1010, A2 (2025).</h3>
 
-<tags><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span><span>Soft-matter-singularities</span><span>Drops</span></tags>
+<div class="tags"><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span><span>Soft-matter-singularities</span><span>Drops</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2025.237)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2408.05089&color=green)](https://arxiv.org/abs/2408.05089)
@@ -135,7 +135,7 @@ title: Research
 
 <h3 id="15">[15] <strong>Sanjay, V.</strong>, & Lohse, D. Unifying theory of scaling in drop impact: Forces & maximum spreading diameter. Phys. Rev. Lett., 134, 104003 (2025).</h3>
 
-<tags><span>Drops</span><span>Dissipative anomaly</span><span>Superamphiphobic-surfaces</span><span>Impact forces</span></tags>
+<div class="tags"><span>Drops</span><span>Dissipative anomaly</span><span>Superamphiphobic-surfaces</span><span>Impact forces</span></div>
 
 [![PRL](https://img.shields.io/static/v1.svg?style=flat-square&label=PRL&message=OA&color=orange)](https://doi.org/10.1103/PhysRevLett.134.104003)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2408.12714&color=green)](https://arxiv.org/abs/2408.12714)
@@ -146,7 +146,7 @@ title: Research
 
 <h3 id="14">[14] <strong>Sanjay, V.</strong>, Zhang, B., Lv, C., & Lohse, D. The role of viscosity on drop impact forces on non-wetting surfaces. J. Fluid Mech., 1004, A6 (2025).</h3>
 
-<tags><span>Drops</span><span>Impact forces</span></tags>
+<div class="tags"><span>Drops</span><span>Impact forces</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2024.982)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2311.03012&color=green)](https://arxiv.org/abs/2311.03012)
@@ -167,7 +167,7 @@ title: Research
 
 <h3 id="13">[13] Kayal, L., <strong>Sanjay, V.</strong>, Yewale, N., Kumar, A., & Dasgupta, R. Focusing of concentric free-surface waves. J. Fluid Mech., 1003, A14 (2025).</h3>
 
-<tags><span>Waves</span><span>Dissipative anomaly</span></tags>
+<div class="tags"><span>Waves</span><span>Dissipative anomaly</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2024.1089)
 [![arXiv](https://img.shields.io/static/v1.svg?style=flat-square&label=arXiv&message=2406.05416&color=green)](https://arxiv.org/abs/2406.05416)
@@ -180,7 +180,7 @@ title: Research
 
 <h3 id="12">[12] Balasubramanian, A. G., <strong>Sanjay, V.</strong>, Jalaal, M., Vinuesa, R., & Tammisola, O. Bursting bubble in an elastoviscoplastic medium. J. Fluid Mech., 1001, A9 (2024).</h3>
 
-<tags><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span><span>Soft-matter-singularities</span></tags>
+<div class="tags"><span>Bubbles</span><span>Non-Newtonian</span><span>Jets</span><span>Soft-matter-singularities</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2024.1073)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/2023_Bubble-bursting-in-an-elasto-viscoplastic-medium)
@@ -202,7 +202,7 @@ title: Research
 
 <h3 id="11">[11] <strong>Sanjay, V.</strong>, Chantelot, P., & Lohse, D. When does an impacting drop stop bouncing? J. Fluid Mech., 958, A26 (2023).</h3>
 
-<tags><span>Drops</span><span>Bouncing</span><span>Dissipative anomaly</span><span>Featured</span></tags>
+<div class="tags"><span>Drops</span><span>Bouncing</span><span>Dissipative anomaly</span><span>Featured</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2023.55)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/comphy-lab/Drop-Impact)
@@ -212,7 +212,7 @@ title: Research
 
 <h3 id="10">[10] <strong>Sanjay, V.</strong>, Lakshman, S., Chantelot, P., Snoeijer, J. H., & Lohse, D. Drop impact on viscous liquid films. J. Fluid Mech., 958, A25 (2023).</h3>
 
-<tags><span>Drops</span><span>Bouncing</span><span>Superhydrophobic surfaces</span></tags>
+<div class="tags"><span>Drops</span><span>Bouncing</span><span>Superhydrophobic surfaces</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2023.13)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/VatsalSy/Drop-impact-on-viscous-liquid-films)
@@ -224,7 +224,7 @@ title: Research
 
 <h3 id="thesis">➡️ <strong>Sanjay, V.</strong> Viscous free-surface flows. Ph.D. Thesis, Physics of Fluids, University of Twente (2022).</h3>
 
-<tags><span>Drops</span><span>Jets</span><span>Sheets</span><span>Bubbles</span><span>Soft-matter-singularities</span><span>Non-Newtonian</span></tags>
+<div class="tags"><span>Drops</span><span>Jets</span><span>Sheets</span><span>Bubbles</span><span>Soft-matter-singularities</span><span>Non-Newtonian</span></div>
 
 [![PhD thesis](https://img.shields.io/static/v1.svg?logo=adobeacrobatreader&style=flat-square&label=Thesis&message=Download&color=green)](https://qrco.de/bd9SHU)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=UT&message=link&color=orange)](https://doi.org/10.3990/1.9789036554077)
@@ -234,7 +234,7 @@ title: Research
 
 <h3 id="9">[9] <strong>Sanjay, V.</strong>, Sen, U., Kant, P., and Lohse, D. Taylor–Culick retractions and the influence of the surroundings. J. Fluid Mech., 948, A14 (2022).</h3>
 
-<tags><span>Sheets</span><span>Dissipative anomaly</span><span>Retraction</span></tags>
+<div class="tags"><span>Sheets</span><span>Dissipative anomaly</span><span>Retraction</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2022.671)
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/VatsalSy/Taylor-Culick-retractions)
@@ -244,7 +244,7 @@ title: Research
 
 <h3 id="8">[8] Zhang, B., <strong>Sanjay, V.</strong>, Shi, S., and Zhao, Y., and Lv, C., and Feng, X.-Q., & Lohse, D. Impact forces of water drops falling on superhydrophobic surfaces. Phys. Rev. Lett., 129(10), 104501 (2022).</h3>
 
-<tags><span>Drops</span><span>Superhydrophobic surfaces</span><span>Impact forces</span></tags>
+<div class="tags"><span>Drops</span><span>Superhydrophobic surfaces</span><span>Impact forces</span></div>
 
 [![GitHub](https://img.shields.io/badge/GitHub-100000?style=flat-square&logo=github&logoColor=white)](https://github.com/VatsalSy/Impact-forces-of-water-drops-falling-on-superhydrophobic-surfaces)
 [![PDF](https://img.shields.io/static/v1.svg?logo=adobeacrobatreader&style=flat-square&label=PDF&message=Download&color=green)](https://qrco.de/bd9aV3)
@@ -264,7 +264,7 @@ title: Research
 
 <h3 id="7">[7] <strong>Sanjay, V.</strong>, Lohse, D., & Jalaal, M. Bursting bubble in a viscoplastic medium. J. Fluid Mech., 922, A2 (2021).</h3>
 
-<tags><span>Bubbles</span><span>Jets</span><span>Non-Newtonian</span><span>Soft-matter-singularities</span></tags>
+<div class="tags"><span>Bubbles</span><span>Jets</span><span>Non-Newtonian</span><span>Soft-matter-singularities</span></div>
 
 [![JFM](https://img.shields.io/static/v1.svg?style=flat-square&label=JFM&message=OA&color=orange)](https://doi.org/10.1017/jfm.2021.489)
 [![arXiv](https://img.shields.io/badge/arXiv-2101.07744-green?style=flat-square)](https://arxiv.org/abs/2101.07744)
@@ -277,7 +277,7 @@ title: Research
 
 <h3 id="6">[6] Ramírez-Soto, O., <strong>Sanjay, V.</strong>, Lohse, D., Pham, J. T., & Vollmer, D. Lifting a sessile oil drop from a superamphiphobic surface with an impacting one. Sci. Adv., 6(34), eaba4330 (2020).</h3>
 
-<tags><span>Drops</span><span>Superamphiphobic-surfaces</span><span>Lifting</span></tags>
+<div class="tags"><span>Drops</span><span>Superamphiphobic-surfaces</span><span>Lifting</span></div>
 
 [![Sci. Adv.](https://img.shields.io/static/v1.svg?style=flat-square&label=Sci.%20Adv.&message=OA&color=orange)](https://doi.org/10.1126/sciadv.aba4330)
 [![arXiv](https://img.shields.io/badge/arXiv-1912.02667-green?style=flat-square)](https://arxiv.org/abs/1912.02667)
@@ -290,7 +290,7 @@ title: Research
 
 <h3 id="5">[5] Jain, A., <strong>Sanjay, V.</strong>, & Das, A. K. Consequences of inclined and dual jet impingement in stagnant liquid and stratified layers. AIChE J., 65(1), 372-384 (2019).</h3>
 
-<tags><span>Jets</span><span>Bubbles</span></tags>
+<div class="tags"><span>Jets</span><span>Bubbles</span></div>
 
 [![PDF](https://img.shields.io/static/v1.svg?style=flat-square&label=PDF&message=Available&color=green)](https://www.dropbox.com/scl/fi/ug7njhulcy9zq8lib911j/2019-Vatsal-_Consequences-of-Inclined-and-Dual-Jet-Impingement-in-Stagnant-Liquid-and-Stratified-Layers.pdf?rlkey=l00thknv7wt55sb0bcuiy8isw&dl=0)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=DOI&message=10.1002/aic.16373&color=orange)](https://doi.org/10.1002/aic.16373)
@@ -302,7 +302,7 @@ title: Research
 
 <h3 id="4">[4] Soni, A., <strong>Sanjay, V.</strong>, & Das, A. K. Formation of fluid structures due to jet-jet and jet-sheet interactions. Chem. Eng. Sci., 191, 67-77 (2018).</h3>
 
-<tags><span>Jets</span></tags>
+<div class="tags"><span>Jets</span></div>
 
 [![PDF](https://img.shields.io/static/v1.svg?style=flat-square&label=PDF&message=Available&color=green)](https://www.dropbox.com/scl/fi/zbs17s77qlu2l2i4c6sak/2018-Vatsal-preprint-_Formation-of-fluid-structures-due-to-jet-jet-and-jet-sheet-interactions.pdf?rlkey=beya847mr9hf8bbdabwyanrmf&dl=0)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=DOI&message=10.1016/j.ces.2018.06.055&color=orange)](https://doi.org/10.1016/j.ces.2018.06.055)
@@ -312,7 +312,7 @@ title: Research
 
 <h3 id="3">[3] <strong>Sanjay, V.</strong>, Das, A.K. Numerical assessment of hazard in compartmental fire having steady heat release rate from the source. Build. Simul. 11, 613–624 (2018).</h3>
 
-<tags><span>Others</span><span>Fire</span><span>Evacuation</span></tags>
+<div class="tags"><span>Others</span><span>Fire</span><span>Evacuation</span></div>
 
 [![PDF](https://img.shields.io/static/v1.svg?style=flat-square&label=PDF&message=Available&color=green)](https://www.dropbox.com/scl/fi/c9vob7a6kso4ai4mygpj2/2018-Vatsal-_Numerical-assessment-of-hazard-in-compartmental-fire-having-steady-heat-release-rate-from-the-source.pdf?rlkey=e8rjz2d3e8nt0xof863i3xb3p&dl=0)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=DOI&message=10.1007/s12273-017-0411-y&color=orange)](https://doi.org/10.1007/s12273-017-0411-y)
@@ -324,7 +324,7 @@ title: Research
 
 <h3 id="2">[2] <strong>Sanjay, V.</strong>, & Das, A. K. Formation of liquid chain by collision of two laminar jets. Phys. Fluids, 29(11), 112101 (2017).</h3>
 
-<tags><span>Jets</span><span>Sheets</span></tags>
+<div class="tags"><span>Jets</span><span>Sheets</span></div>
 
 [![PDF](https://img.shields.io/static/v1.svg?style=flat-square&label=PDF&message=Available&color=green)](https://www.dropbox.com/scl/fi/fmk08c3z9twdat138v8b3/2017-Vatsal-preprint-_Formation-of-liquid-chain-by-collision-of-two-laminar-jets.pdf?rlkey=imwh2a606aecpbvjq3ctdq168&dl=0)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=DOI&message=10.1063/1.4998288&color=orange)](https://doi.org/10.1063/1.4998288)
@@ -335,7 +335,7 @@ title: Research
 
 <h3 id="1">[1] <strong>Sanjay, V.</strong>, & Das, A. K. On air entrainment in a water pool by impingement of a jet. AIChE J., 63(11), 5169-5181 (2017).</h3>
 
-<tags><span>Jets</span><span>Bubbles</span></tags>
+<div class="tags"><span>Jets</span><span>Bubbles</span></div>
 
 [![PDF](https://img.shields.io/static/v1.svg?style=flat-square&label=PDF&message=Available&color=green)](https://www.dropbox.com/scl/fi/37ek49y5ae1t1lr18q95n/2017-Vatsal-preprint-_On-Air-Entrainment-in-a-Water-pool-by-Impingement-of-a-Jet.pdf?rlkey=iqb3ejms8t990owpiuqmpy0k6&dl=0)
 [![DOI](https://img.shields.io/static/v1.svg?style=flat-square&label=DOI&message=10.1002/aic.15828&color=orange)](https://doi.org/10.1002/aic.15828)
diff --git a/assets/css/research.css b/assets/css/research.css
index 2b02880..c779c34 100644
--- a/assets/css/research.css
+++ b/assets/css/research.css
@@ -631,7 +631,7 @@
 }
 
 /* Tags styling */
-.research-content tags {
+.research-content .tags {
   display: inline-flex;
   gap: 0.5rem;
   font-size: 1.4rem;
@@ -640,7 +640,7 @@
 }
 
 /* Style each tag separately */
-.research-content tags span {
+.research-content .tags span {
   background: var(--color-primary-alpha-15);
   color: var(--color-primary);
   padding: 0.4rem 1rem;
@@ -653,29 +653,29 @@
   user-select: none;
 }
 
-[data-theme="dark"] .research-content tags span {
+[data-theme="dark"] .research-content .tags span {
   background: var(--color-blue-bright-alpha-20);
   color: var(--research-text-color);
   border: 1px solid var(--color-blue-bright-alpha-30);
 }
 
 /* Fix for top filter tags in dark theme */
-[data-theme="dark"] tags span,
-[data-theme="dark"] tags a.tag-link {
+[data-theme="dark"] .tags span,
+[data-theme="dark"] .tags a.tag-link {
   background: var(--color-blue-bright-alpha-20);
   color: var(--research-text-color);
   border: 1px solid var(--color-blue-bright-alpha-40);
 }
 
-[data-theme="dark"] tags span:hover,
-[data-theme="dark"] tags a.tag-link:hover {
+[data-theme="dark"] .tags span:hover,
+[data-theme="dark"] .tags a.tag-link:hover {
   background: var(--color-blue-bright-alpha-20);
   border-color: var(--color-blue-bright-alpha-40);
 }
 
 /* Fix for active tags in dark theme */
-[data-theme="dark"] tags span.active,
-[data-theme="dark"] tags a.tag-link.active {
+[data-theme="dark"] .tags span.active,
+[data-theme="dark"] .tags a.tag-link.active {
   background: var(--color-blue-bright-alpha-80);
   color: var(--research-text-color);
   border-color: var(--color-blue-bright-alpha-40);
@@ -683,56 +683,56 @@
   box-shadow: 0 2px 5px var(--color-blue-bright-alpha-40);
 }
 
-.research-content tags span:nth-of-type(1) {
+.research-content .tags span:nth-of-type(1) {
   background: var(--color-primary-alpha-15);
 }
 
-[data-theme="dark"] .research-content tags span:nth-of-type(1) {
+[data-theme="dark"] .research-content .tags span:nth-of-type(1) {
   background: var(--color-blue-bright-alpha-20);
 }
 
-.research-content tags span:nth-of-type(2) {
+.research-content .tags span:nth-of-type(2) {
   background: var(--color-primary-alpha-10);
 }
 
-[data-theme="dark"] .research-content tags span:nth-of-type(2) {
+[data-theme="dark"] .research-content .tags span:nth-of-type(2) {
   background: var(--color-blue-bright-alpha-15);
 }
 
-.research-content tags span:nth-of-type(3) {
+.research-content .tags span:nth-of-type(3) {
   background: var(--color-primary-alpha-5);
 }
 
-[data-theme="dark"] .research-content tags span:nth-of-type(3) {
+[data-theme="dark"] .research-content .tags span:nth-of-type(3) {
   background: var(--color-blue-bright-alpha-10);
 }
 
-.research-content tags span:nth-of-type(n + 4) {
+.research-content .tags span:nth-of-type(n + 4) {
   background: var(--color-primary-alpha-5);
 }
 
-[data-theme="dark"] .research-content tags span:nth-of-type(n + 4) {
+[data-theme="dark"] .research-content .tags span:nth-of-type(n + 4) {
   background: var(--color-blue-bright-alpha-10);
 }
 
-.research-content tags span:hover {
+.research-content .tags span:hover {
   transform: scale(1.1);
   box-shadow: 0 2px 5px var(--color-primary-alpha-10);
 }
 
-[data-theme="dark"] .research-content tags span:hover {
+[data-theme="dark"] .research-content .tags span:hover {
   box-shadow: 0 2px 5px rgba(120, 170, 255, 0.3);
   background: var(--color-blue-bright-alpha-30);
 }
 
-.research-content tags span.active {
+.research-content .tags span.active {
   background: #9333ea;
   color: var(--color-white);
   transform: scale(1.1);
   box-shadow: 0 2px 5px rgba(147, 51, 234, 0.2);
 }
 
-[data-theme="dark"] .research-content tags span.active {
+[data-theme="dark"] .research-content .tags span.active {
   background: #4d8dff;
   color: var(--color-white);
   box-shadow: 0 2px 6px rgba(77, 141, 255, 0.4);
@@ -745,11 +745,11 @@
 
 /* Responsive adjustments for tags */
 @media screen and (max-width: 600px) {
-  .research-content tags {
+  .research-content .tags {
     font-size: 1rem;
   }
 
-  .research-content tags span {
+  .research-content .tags span {
     padding: 0.3rem 0.8rem;
   }
 }
@@ -800,8 +800,8 @@ html {
   opacity: 1; /* Ensure visibility */
 }
 /* Tag minimal */
-[data-theme="dark"] tags span,
-[data-theme="dark"] tags a.tag-link {
+[data-theme="dark"] .tags span,
+[data-theme="dark"] .tags a.tag-link {
   background-color: var(--research-bg-color); /* Corrected variable */
   color: var(--research-text-color);
   border: 1px solid var(--color-blue-bright-alpha-30);
diff --git a/assets/css/styles.css b/assets/css/styles.css
index 1c0ccb3..75c9c7f 100644
--- a/assets/css/styles.css
+++ b/assets/css/styles.css
@@ -1758,14 +1758,14 @@ section#featured:after,
 }
 
 /* Style tags */
-.featured-paper tags {
+.featured-paper .tags {
   display: flex;
   flex-wrap: wrap;
   gap: 0.5rem;
   margin: 1rem 0;
 }
 
-.featured-paper tags span {
+.featured-paper .tags span {
   display: inline-block;
   padding: 0.4rem 0.8rem;
   background: var(--tag-bg);
@@ -1778,7 +1778,7 @@ section#featured:after,
   border: 1px solid var(--tag-border);
 }
 
-.featured-paper tags span:hover {
+.featured-paper .tags span:hover {
   background: var(--tag-bg-hover);
   transform: translateY(-2px);
   border-color: var(--tag-border-hover);
diff --git a/assets/js/command-data.js b/assets/js/command-data.js
index fa9610a..2b5a4a7 100644
--- a/assets/js/command-data.js
+++ b/assets/js/command-data.js
@@ -245,7 +245,7 @@
               window.matchMedia("(prefers-color-scheme: dark)").matches;
 
             // Collect all unique tags from the page
-            const tagElements = document.querySelectorAll("tags span");
+            const tagElements = document.querySelectorAll(".tags span");
             const tags = new Set();
             tagElements.forEach((tag) => {
               tags.add(tag.textContent);
@@ -327,7 +327,7 @@
                 // Find the actual tag in the document and simulate a click on it
                 const tagText = btn.textContent;
                 const matchingTag = Array.from(
-                  document.querySelectorAll("tags span")
+                  document.querySelectorAll(".tags span")
                 ).find((tag) => tag.textContent === tagText);
 
                 if (matchingTag) {
diff --git a/assets/js/main.js b/assets/js/main.js
index 9803290..8836dab 100644
--- a/assets/js/main.js
+++ b/assets/js/main.js
@@ -161,7 +161,7 @@
         let featuredSections = Array.from(paperSections).filter((section) => {
           // Find the next tags element
           let nextEl = section.nextElementSibling;
-          while (nextEl && !nextEl.matches("tags")) {
+          while (nextEl && !nextEl.matches(".tags")) {
             nextEl = nextEl.nextElementSibling;
           }
           return nextEl && nextEl.textContent.includes("Featured");
@@ -227,7 +227,7 @@
               const clone = nextEl.cloneNode(true);
 
               // If it's a tags element, make spans clickable
-              if (clone.matches("tags")) {
+              if (clone.matches(".tags")) {
                 Array.from(clone.children).forEach((span) => {
                   span.style.cursor = "pointer";
                   span.addEventListener("click", (e) => {
@@ -253,7 +253,7 @@
               // Don't navigate if clicking on a link, tag, or iframe
               if (
                 e.target.closest("a") ||
-                e.target.closest("tags") ||
+                e.target.closest(".tags") ||
                 e.target.closest("iframe")
               ) {
                 return;
diff --git a/scripts/deploy.sh b/scripts/deploy.sh
index 297756f..1b5da36 100755
--- a/scripts/deploy.sh
+++ b/scripts/deploy.sh
@@ -3,7 +3,7 @@
 # deploy.sh - Find an available port and start Jekyll development server
 # Usage: ./scripts/deploy.sh [OPTIONS]
 
-set -e
+set -euo pipefail
 
 # Color codes for output
 GREEN='\033[0;32m'
@@ -25,6 +25,27 @@ ENABLE_INCREMENTAL=false
 CUSTOM_PORT=""
 CUSTOM_HOST="localhost"
 OPEN_BROWSER=false
+LIVERELOAD_PORT=""
+
+check_requirements() {
+    if ! command -v lsof >/dev/null 2>&1; then
+        echo -e "${RED}Error: lsof is required but not installed.${NC}"
+        echo "Install lsof and rerun './scripts/deploy.sh'"
+        exit 1
+    fi
+
+    if ! command -v bundle >/dev/null 2>&1; then
+        echo -e "${RED}Error: bundler is required but not installed.${NC}"
+        echo "Run './scripts/setup.sh' and rerun './scripts/deploy.sh'"
+        exit 1
+    fi
+
+    if ! bundle exec jekyll --version >/dev/null 2>&1; then
+        echo -e "${RED}Error: Jekyll is not available in the current bundle.${NC}"
+        echo "Run './scripts/setup.sh' and rerun './scripts/deploy.sh'"
+        exit 1
+    fi
+}
 
 show_help() {
     cat << EOF
@@ -75,7 +96,13 @@ while [[ $# -gt 0 ]]; do
                 echo "Run './scripts/deploy.sh --help' for usage information"
                 exit 1
             fi
-            CUSTOM_PORT="$2"
+            parsed_port=$((10#$2))
+            if (( parsed_port < 1 || parsed_port > 65535 )); then
+                echo -e "${RED}Error: -p|--port must be between 1 and 65535${NC}"
+                echo "Run './scripts/deploy.sh --help' for usage information"
+                exit 1
+            fi
+            CUSTOM_PORT="$parsed_port"
             shift 2
             ;;
         --host)
@@ -84,6 +111,11 @@ while [[ $# -gt 0 ]]; do
                 echo "Run './scripts/deploy.sh --help' for usage information"
                 exit 1
             fi
+            if [[ ! "$2" =~ ^[A-Za-z0-9._:-]+$ ]]; then
+                echo -e "${RED}Error: --host contains invalid characters${NC}"
+                echo "Run './scripts/deploy.sh --help' for usage information"
+                exit 1
+            fi
             CUSTOM_HOST="$2"
             shift 2
             ;;
@@ -115,7 +147,7 @@ done
 is_port_available() {
     local port=$1
     # Check if port is in use using lsof
-    if lsof -i :$port >/dev/null 2>&1; then
+    if lsof -i :"$port" >/dev/null 2>&1; then
         return 1  # Port is in use
     else
         return 0  # Port is available
@@ -160,52 +192,58 @@ echo -e "${BLUE}  Jekyll Development Server${NC}"
 echo -e "${BLUE}================================${NC}"
 echo ""
 
+check_requirements
+
 # Determine port to use
 if [ -n "$CUSTOM_PORT" ]; then
     echo -e "${BLUE}Using custom port: ${CUSTOM_PORT}${NC}"
-    if ! is_port_available $CUSTOM_PORT; then
+    if ! is_port_available "$CUSTOM_PORT"; then
         echo -e "${YELLOW}⚠ Warning: Port ${CUSTOM_PORT} is already in use${NC}"
         echo -e "${YELLOW}Server may fail to start or conflict with existing service${NC}"
     fi
     PORT=$CUSTOM_PORT
 else
     # Find an available port
-    PORT=$(find_available_port)
-
-    if [ -z "$PORT" ]; then
+    if ! PORT=$(find_available_port); then
         echo -e "${RED}Failed to find an available port. Exiting.${NC}"
         exit 1
     fi
 fi
 
-# Build Jekyll command with options
-JEKYLL_CMD="bundle exec jekyll serve --port $PORT --host $CUSTOM_HOST"
+# Build Jekyll command with options safely as an array
+JEKYLL_CMD=(bundle exec jekyll serve --port "$PORT" --host "$CUSTOM_HOST")
 
 # Add livereload if enabled
 if [ "$ENABLE_LIVERELOAD" = true ]; then
-    LIVERELOAD_PORT=$(find_available_livereload_port)
-
-    if [ -z "$LIVERELOAD_PORT" ]; then
+    if ! LIVERELOAD_PORT=$(find_available_livereload_port); then
         echo -e "${RED}Failed to find an available livereload port. Disabling livereload.${NC}"
+        ENABLE_LIVERELOAD=false
+        LIVERELOAD_PORT=""
     else
-        JEKYLL_CMD="$JEKYLL_CMD --livereload --livereload-port $LIVERELOAD_PORT"
+        JEKYLL_CMD+=(--livereload --livereload-port "$LIVERELOAD_PORT")
     fi
 fi
 
+# Derive URL-safe host for display/open (bracket IPv6 literals)
+URL_HOST="$CUSTOM_HOST"
+if [[ "$URL_HOST" == *:* && "$URL_HOST" != \[*\] ]]; then
+    URL_HOST="[$URL_HOST]"
+fi
+
 # Add drafts if enabled
 if [ "$ENABLE_DRAFTS" = true ]; then
-    JEKYLL_CMD="$JEKYLL_CMD --drafts"
+    JEKYLL_CMD+=(--drafts)
 fi
 
 # Add incremental if enabled
 if [ "$ENABLE_INCREMENTAL" = true ]; then
-    JEKYLL_CMD="$JEKYLL_CMD --incremental"
+    JEKYLL_CMD+=(--incremental)
 fi
 
 # Display server configuration
 echo ""
 echo -e "${GREEN}🚀 Starting Jekyll server...${NC}"
-echo -e "${YELLOW}📍 URL: http://${CUSTOM_HOST}:${PORT}${NC}"
+echo -e "${YELLOW}📍 URL: http://${URL_HOST}:${PORT}${NC}"
 [ "$ENABLE_LIVERELOAD" = true ] && [ -n "$LIVERELOAD_PORT" ] && \
     echo -e "${GREEN}🔄 Live reload: enabled (port ${LIVERELOAD_PORT})${NC}"
 [ "$ENABLE_DRAFTS" = true ] && \
@@ -221,13 +259,13 @@ echo ""
 if [ "$OPEN_BROWSER" = true ]; then
     echo -e "${GREEN}🌐 Opening browser...${NC}"
     if [[ "$OSTYPE" == "darwin"* ]]; then
-        open "http://${CUSTOM_HOST}:${PORT}" &
+        open "http://${URL_HOST}:${PORT}" &
     elif [[ "$OSTYPE" == "linux-gnu"* ]]; then
-        xdg-open "http://${CUSTOM_HOST}:${PORT}" &
+        xdg-open "http://${URL_HOST}:${PORT}" &
     else
         echo -e "${YELLOW}⚠ Auto-open not supported on this platform${NC}"
     fi
 fi
 
 # Start Jekyll with the configured options
-$JEKYLL_CMD
+"${JEKYLL_CMD[@]}"
diff --git a/scripts/generate_filtered_research.rb b/scripts/generate_filtered_research.rb
index a7d69e4..9cc11d6 100755
--- a/scripts/generate_filtered_research.rb
+++ b/scripts/generate_filtered_research.rb
@@ -16,7 +16,7 @@
 
 # Find all unique tags
 all_tags = []
-doc.css('tags span').each do |tag|
+doc.css('.tags span').each do |tag|
   all_tags << tag.text unless all_tags.include?(tag.text)
 end
 
diff --git a/scripts/validate-content-rules.sh b/scripts/validate-content-rules.sh
new file mode 100755
index 0000000..8cb9d36
--- /dev/null
+++ b/scripts/validate-content-rules.sh
@@ -0,0 +1,156 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+HISTORY_FILE="$REPO_ROOT/history.md"
+RESEARCH_FILE="$REPO_ROOT/_research/index.md"
+ADD_NEWS_RULES_FILE="$REPO_ROOT/.opencode/commands/add-news.md"
+CLAUDE_FILE="$REPO_ROOT/CLAUDE.md"
+README_FILE="$REPO_ROOT/README.md"
+ADD_PAPER_RULES_FILE="$REPO_ROOT/.opencode/commands/add-paper.md"
+
+FAILURES=0
+
+log_error() {
+  echo "✗ $1"
+  FAILURES=$((FAILURES + 1))
+}
+
+has_match() {
+  local pattern="$1"
+  local file="$2"
+
+  if command -v rg >/dev/null 2>&1; then
+    rg -q "$pattern" "$file"
+  else
+    grep -Eq "$pattern" "$file"
+  fi
+}
+
+require_file() {
+  local file="$1"
+  if [[ ! -f "$file" ]]; then
+    log_error "Required file not found: $file"
+    return 1
+  fi
+}
+
+validate_history_order() {
+  if ! require_file "$HISTORY_FILE"; then
+    # Missing file already counted in FAILURES; keep running other validations.
+    return 0
+  fi
+  local previous_year=99999
+  local current_year=""
+  local previous_month=13
+
+  month_to_number() {
+    case "$1" in
+      January) echo 1 ;;
+      February) echo 2 ;;
+      March) echo 3 ;;
+      April) echo 4 ;;
+      May) echo 5 ;;
+      June) echo 6 ;;
+      July) echo 7 ;;
+      August) echo 8 ;;
+      September) echo 9 ;;
+      October) echo 10 ;;
+      November) echo 11 ;;
+      December) echo 12 ;;
+      *) echo 0 ;;
+    esac
+  }
+
+  while IFS= read -r line; do
+    if [[ $line =~ ^##[[:space:]]+([0-9]{4})[[:space:]]*$ ]]; then
+      local year="${BASH_REMATCH[1]}"
+      if (( year >= previous_year )); then
+        log_error "history.md year heading '$year' is out of order. Years must be descending."
+      fi
+      previous_year=$year
+      current_year=$year
+      previous_month=13
+      continue
+    fi
+
+    if [[ $line =~ ^###[[:space:]]+(.+)[[:space:]]*$ ]]; then
+      local section_heading="${BASH_REMATCH[1]}"
+      if [[ $section_heading =~ ^[A-Za-z]+$ ]]; then
+        local month_name="$section_heading"
+        local month_number
+        month_number="$(month_to_number "$month_name")"
+        if (( month_number == 0 )); then
+          log_error "history.md has invalid month heading '$month_name'. Use full English month names (January-December)."
+          continue
+        fi
+        if [[ -z "$current_year" ]]; then
+          log_error "history.md month '$month_name' appears before any year heading."
+          continue
+        fi
+        if (( month_number >= previous_month )); then
+          log_error "history.md month '$month_name' is out of order in $current_year. Months must be reverse chronological (December to January)."
+        fi
+        previous_month=$month_number
+      fi
+    fi
+  done < "$HISTORY_FILE"
+}
+
+validate_research_tags() {
+  if ! require_file "$RESEARCH_FILE"; then
+    # Missing file already counted in FAILURES; keep running other validations.
+    return 0
+  fi
+
+  if has_match "<tags>|</tags>" "$RESEARCH_FILE"; then
+    log_error "_research/index.md still contains <tags> elements. Use <div class=\"tags\"> blocks."
+  fi
+
+  if ! has_match "<div class=\"tags\">" "$RESEARCH_FILE"; then
+    log_error "_research/index.md is missing <div class=\"tags\"> blocks."
+  fi
+}
+
+validate_docs_rules() {
+  local missing_required_file=0
+
+  require_file "$ADD_NEWS_RULES_FILE" || missing_required_file=1
+  require_file "$CLAUDE_FILE" || missing_required_file=1
+  require_file "$README_FILE" || missing_required_file=1
+  require_file "$ADD_PAPER_RULES_FILE" || missing_required_file=1
+
+  if (( missing_required_file > 0 )); then
+    # Missing files already counted in FAILURES; skip content checks safely.
+    return 0
+  fi
+
+  if ! has_match "reverse chronological order" "$ADD_NEWS_RULES_FILE"; then
+    log_error ".opencode/commands/add-news.md must state reverse chronological month ordering."
+  fi
+
+  if has_match "<tags>|</tags>" "$CLAUDE_FILE"; then
+    log_error "CLAUDE.md still documents deprecated <tags> markup."
+  fi
+
+  if has_match "<tags>|</tags>" "$README_FILE"; then
+    log_error "README.md still documents deprecated <tags> markup."
+  fi
+
+  if has_match "<tags>|</tags>" "$ADD_PAPER_RULES_FILE"; then
+    log_error ".opencode/commands/add-paper.md still documents deprecated <tags> markup."
+  fi
+}
+
+validate_history_order
+validate_research_tags
+validate_docs_rules
+
+if (( FAILURES > 0 )); then
+  echo ""
+  echo "Validation failed with $FAILURES issue(s)."
+  exit 1
+fi
+
+echo "✓ Content ordering and research tag rules passed."