style: update table border color and selector specificity

Author: julioest

docs/ui/src/css/doc.css

@@ -277,7 +277,7 @@
 
 .doc table.tableblock,
 .doc table.tableblock > * > tr > * {
-  border: 0 solid var(--table-border-color);
+  border: 0 solid rgba(255, 255, 255, 0.4);
 }
 
 .doc table.grid-all > * > tr > * {
@@ -1087,7 +1087,7 @@
   padding: 0;
 }
 
-.doc table.tableblock td:has(a) a {
+.doc table.tableblock td:has(.image a) .image a {
   display: block;
   width: 100%;
   height: 100%;