Fix dark mode readability, add new protocols to landing page

- Add explicit white backgrounds to body, features, and requirements
  sections so text stays readable in dark mode
- Add color-scheme: light to prevent browser dark mode overrides
- Add Fiat V1, Mazda V0, Mitsubishi V0, Porsche Touareg to protocol
  list and doc links on landing page
- Update protocol count to 18

docs/index.html

@@ -48,7 +48,7 @@
                     </div>
                     <div class="feature-card">
                         <h3>🔓 Multi-Protocol Decoding</h3>
-                        <p>14 protocol decoders including Kia V0–V6, Ford, Fiat, Subaru, Suzuki, VAG, PSA, and more</p>
+                        <p>18 protocol decoders including Kia V0–V6, Ford, Fiat, Mazda, Mitsubishi, Porsche, Subaru, Suzuki, VAG, PSA, and more</p>
                     </div>
                     <div class="feature-card">
                         <h3>🔑 KeeLoq Keystore</h3>
@@ -89,7 +89,10 @@
                         <h3>Other Manufacturers</h3>
                         <ul>
                             <li>Ford V0</li>
-                            <li>Fiat V0</li>
+                            <li>Fiat V0 / V1</li>
+                            <li>Mazda V0</li>
+                            <li>Mitsubishi V0</li>
+                            <li>Porsche Touareg</li>
                             <li>Subaru</li>
                             <li>Suzuki</li>
                             <li>VAG (VW/Audi/Seat/Skoda)</li>
@@ -142,6 +145,10 @@
                     <a href="kia_v6.html" class="doc-link">Kia V6</a>
                     <a href="ford_v0.html" class="doc-link">Ford V0</a>
                     <a href="fiat_v0.html" class="doc-link">Fiat V0</a>
+                    <a href="fiat_v1.html" class="doc-link">Fiat V1</a>
+                    <a href="mazda_v0.html" class="doc-link">Mazda V0</a>
+                    <a href="mitsubishi_v0.html" class="doc-link">Mitsubishi V0</a>
+                    <a href="porsche_touareg.html" class="doc-link">Porsche Touareg</a>
                     <a href="subaru.html" class="doc-link">Subaru</a>
                     <a href="suzuki.html" class="doc-link">Suzuki</a>
                     <a href="vag.html" class="doc-link">VAG</a>

docs/style.css

@@ -20,7 +20,9 @@ html {
 body {
     font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
     color: var(--text-color);
+    background-color: white;
     line-height: 1.6;
+    color-scheme: light;
 }
 
 .container {
@@ -135,6 +137,7 @@ header .tagline {
 /* Features Section */
 .features {
     padding: 60px 0;
+    background: white;
 }
 
 .features h2 {
@@ -213,6 +216,7 @@ header .tagline {
 /* Requirements Section */
 .requirements {
     padding: 60px 0;
+    background: white;
 }
 
 .requirements h2 {