feat: implement AI gateway phase one runtime

apps/web/src/styles/landing.css

@@ -9,10 +9,10 @@
   align-items: center;
   gap: 12px;
   padding: 10px 16px;
-  border: 1px solid #d7eadf;
-  border-radius: 10px;
-  background: #f1fbf5;
-  color: #155e3d;
+  border: 1px solid #e2e8f0;
+  border-radius: 12px;
+  background: #fff;
+  color: #202734;
 }
 
 .releaseNotice strong {
@@ -20,7 +20,7 @@
 }
 
 .releaseNotice span {
-  color: #43735b;
+  color: var(--muted-foreground);
   font-size: 13px;
 }
 
@@ -32,10 +32,8 @@
   align-items: center;
   padding: 44px;
   border: 1px solid var(--border);
-  border-radius: 12px;
-  background:
-    linear-gradient(120deg, rgba(245, 250, 255, 0.96), rgba(255, 255, 255, 0.9)),
-    #ffffff;
+  border-radius: 14px;
+  background: #ffffff;
 }
 
 .landingCopy {
@@ -66,10 +64,10 @@
   display: grid;
   gap: 16px;
   padding: 18px;
-  border: 1px solid #dbe5ef;
-  border-radius: 10px;
-  background: #f8fafc;
-  box-shadow: 0 18px 45px rgba(16, 24, 40, 0.10);
+  border: 1px solid var(--border);
+  border-radius: 12px;
+  background: #fafbfc;
+  box-shadow: 0 20px 60px rgba(16, 24, 40, 0.08);
 }
 
 .previewHeader,
@@ -98,7 +96,7 @@
   min-height: 92px;
   padding: 14px;
   border: 1px solid var(--border);
-  border-radius: 8px;
+  border-radius: 10px;
   background: #fff;
 }
 
@@ -114,8 +112,8 @@
 
 .previewFlow {
   padding: 14px;
-  border-radius: 8px;
-  background: #102033;
+  border-radius: 10px;
+  background: #111827;
   color: #fff;
   font-size: 12px;
   font-weight: 800;