fix(visual): 1:1 banner/hero/modal + strip non-zibll card chrome

Align banner s-desc caption/scale-height, hero search pill and -40px cards, modal colorful header/spring scale; remove white/pink card borders and hover lifts across mainline surfaces.

assets/css/frontend/forum/board.css

@@ -4,7 +4,7 @@
     padding: 24px;
     border-radius: var(--radius-2xl, 16px);
     background: linear-gradient(180deg, rgba(240,68,148,0.05), rgba(255,255,255,0.96));
-    border: 1px solid rgba(255, 255, 255, 0.55);
+    border: none;
     box-shadow: var(--shadow-sm);
 }
 
@@ -67,7 +67,7 @@
     margin-bottom: 24px;
     padding: 22px;
     background: var(--surface-1, #fff);
-    border: 1px solid rgba(255, 255, 255, 0.55);
+    border: none;
     border-radius: var(--radius-2xl, 16px);
     box-shadow: var(--shadow-sm);
 }
@@ -156,8 +156,8 @@
 .aksrt-forum-board__governance-card {
     padding: 18px;
     background: var(--surface-1, #fff);
-    border: 1px solid rgba(255, 255, 255, 0.55);
-    border-radius: var(--radius-lg, 10px);
+    border: none;
+    border-radius: var(--main-radius, var(--radius, 8px));
     box-shadow: var(--shadow-sm);
 }