style(theme): focus ring in firefly blue

src/routes/layout.css

@@ -32,6 +32,7 @@
   --cladd-surface-cut: oklch(0.955 0.005 240);
   --cladd-bg-outline: oklch(0.88 0.008 240);
   --cladd-outline: oklch(0.9 0.008 240);
+  --ring: var(--ff-brand);
 }
 
 .cladd-color-brand {
@@ -39,6 +40,7 @@
 }
 
 .dark {
+  --ring: var(--ff-series-1);
   --ff-brand: oklch(0.42 0.085 240);
   --ff-brand-deep: oklch(0.36 0.075 240);
   --ff-on-brand: oklch(0.97 0.01 240);