button/chat fixes (#21)

scss/buttons.scss

@@ -34,10 +34,12 @@
   }
 }
 
+.btn-default.sidebar-new-topic-button {
+  border: none;
+}
+
 .btn-default {
   border: 1px solid var(--primary-300);
-  //id like to use rgba of the accent colour but how to derive that?
-  // box-shadow: 0px 0px 8px 2px oklch(from (var(--accent-color)) calc(l * 2) calc(c * 0.125) h);
   background: var(--secondary);
 
   .d-icon {

scss/chat.scss

@@ -31,6 +31,7 @@ body.has-full-page-chat {
   margin-bottom: var(--spacing-block-xs);
   font-size: var(--font-up-1);
   border-radius: var(--d-border-radius);
+  border-bottom: none;
   &:hover {
     background-color: var(--d-sidebar-active-background);
   }