Fix contact page missing stylesheets

The contact page had no CSS entry in the layout's conditional loading,
so it only received styles.css — leaving form inputs, card layout, and
the contact-methods grid completely unstyled. Add content-pages.css and
a new contact.css with form and grid styles.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: congwang-mk

_layouts/default.html

@@ -22,6 +22,9 @@
         <link rel="stylesheet" href="/assets/css/faq.css">
     {% elsif page.url contains '/about' %}
         <link rel="stylesheet" href="/assets/css/about.css">
+    {% elsif page.url contains '/contact' %}
+        <link rel="stylesheet" href="/assets/css/content-pages.css">
+        <link rel="stylesheet" href="/assets/css/contact.css">
     {% elsif page.url == '/' %}
         <link rel="stylesheet" href="/assets/css/products.css">
     {% endif %}

assets/css/contact.css

@@ -0,0 +1,47 @@
+/* ===== CONTACT PAGE STYLES ===== */
+
+/* Form Styles */
+.form-group {
+    margin-bottom: var(--space-5);
+}
+
+.form-group label {
+    display: block;
+    font-size: var(--text-sm);
+    font-weight: 600;
+    color: var(--gray-700);
+    margin-bottom: var(--space-2);
+}
+
+.form-group input, .form-group textarea {
+    width: 100%;
+    padding: var(--space-3) var(--space-4);
+    border: 1px solid var(--gray-300);
+    border-radius: var(--radius-md);
+    font-size: var(--text-sm);
+    font-family: var(--font-body);
+    transition: border-color 0.15s ease;
+    box-sizing: border-box;
+}
+
+.form-group input:focus, .form-group textarea:focus {
+    outline: none;
+    border-color: var(--gray-900);
+    box-shadow: 0 0 0 3px rgba(0, 0, 0, 0.05);
+}
+
+/* Features Grid (for contact methods) */
+.features-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
+    gap: var(--space-6);
+    margin-top: var(--space-8);
+}
+
+/* Responsive */
+@media (max-width: 768px) {
+    .features-grid {
+        grid-template-columns: 1fr;
+        gap: var(--space-4);
+    }
+}