Fix button styling and improve project categorization

- Fix Get In Touch button white-on-white text visibility issue
- Reorganize project categories for better filtering:
  - AI Applications (Neo4j Tutor, Federated Learning, Local Ad Engine)
  - Robotics (Hoody Robot)
  - Machine Learning (Movie Prediction)
  - Design & Hardware (Patented Device)
  - Research & Analysis (Cognitive Modeling, TrueSelect)
- Update filter button labels to be more descriptive
- Ensure proper color contrast for all button states

Author: coding-crying

css/style.css

@@ -170,17 +170,17 @@ header {
 
 .btn-secondary {
     background: transparent;
-    color: var(--link-color) !important;
-    border: 2px solid var(--link-color);
+    color: var(--primary-color) !important;
+    border: 2px solid var(--primary-color);
 }
 
 .btn-secondary:hover {
-    background: var(--link-color);
+    background: var(--primary-color);
     color: var(--bg-color) !important;
 }
 
 .btn-secondary:visited {
-    color: var(--link-color) !important;
+    color: var(--primary-color) !important;
 }
 
 .btn-outline {

projects.html

@@ -35,11 +35,11 @@ <h1>My Projects</h1>
             <div class="container">
                 <div class="filter-buttons">
                     <button class="filter-btn active" data-filter="all">All Projects</button>
-                    <button class="filter-btn" data-filter="web">AI Applications</button>
+                    <button class="filter-btn" data-filter="ai">AI Applications</button>
                     <button class="filter-btn" data-filter="robotics">Robotics</button>
                     <button class="filter-btn" data-filter="ml">Machine Learning</button>
-                    <button class="filter-btn" data-filter="design">Design</button>
-                    <button class="filter-btn" data-filter="tools">Research & Analysis</button>
+                    <button class="filter-btn" data-filter="design">Design & Hardware</button>
+                    <button class="filter-btn" data-filter="research">Research & Analysis</button>
                 </div>
             </div>
         </section>
@@ -48,7 +48,7 @@ <h1>My Projects</h1>
             <div class="container">
                 <div class="projects-grid">
 
-                    <div class="project-card featured" data-category="web">
+                    <div class="project-card featured" data-category="ai">
                         <div class="project-image">
                             <img src="images/neo4j.jpg" alt="Neo4j Language Learning Tutor">
                             <div class="project-overlay">
@@ -92,7 +92,7 @@ <h4>Architectural Achievements:</h4>
                         </div>
                     </div>
 
-                    <div class="project-card" data-category="ml">
+                    <div class="project-card" data-category="ai">
                         <div class="project-image">
                             <div class="project-placeholder">
                                 <div class="placeholder-content">
@@ -262,7 +262,7 @@ <h4>Development Achievements:</h4>
                     </div>
 
 
-                    <div class="project-card" data-category="ml">
+                    <div class="project-card" data-category="research">
                         <div class="project-image">
                             <div class="project-placeholder">
                                 <div class="placeholder-content">
@@ -303,7 +303,7 @@ <h4>Research Findings:</h4>
                         </div>
                     </div>
 
-                    <div class="project-card" data-category="tools">
+                    <div class="project-card" data-category="ai">
                         <div class="project-image">
                         <div class="ad-engine-placeholder">
                             <div class="placeholder-content">
@@ -346,7 +346,7 @@ <h4>System Architecture:</h4>
                         </div>
                     </div>
 
-                    <div class="project-card" data-category="tools">
+                    <div class="project-card" data-category="research">
                         <div class="project-image">
                             <div class="project-placeholder">
                                 <div class="placeholder-content">