Remove unnecessary styling.

packages/chatbox/style/index.css

@@ -17,7 +17,6 @@
   margin-top: -1px;
 }
 
-
 .jp-Chatbox {
   height: 100%;
   padding: 0;
@@ -25,32 +24,22 @@
   flex-direction: column;
 }
 
-
 .jp-Chatbox-content {
   background-color: var(--jp-layout-color2);
   flex: 1 1 auto;
   overflow: auto;
 }
 
-
-.jp-Chatbox-content .jp-Cell.jp-Cell.jp-mod-collapsed.jp-mod-readOnly {
-  padding-left: calc(2*var(--jp-private-console-cell-padding))
-}
-
-
 .jp-Chatbox-input {
   max-height: 80%;
   flex: 0 0 auto;
   overflow: auto;
   border-top: var(--jp-border-width) solid var(--jp-border-color1);
-  padding-top: var(--jp-private-console-cell-padding);
-  padding-right: var(--jp-private-console-cell-padding);
-  padding-left: var(--jp-private-console-cell-padding);
-  /* The weird 8px bottom padding is needed because of the 2px margin in the panel
-  that lets the shadow in the dock panel show */
-  padding-bottom: 8px;
 }
 
+/**
+ * No reason to include space for the In/Out prompt here.
+ */
 .jp-Chatbox .jp-Cell-prompt {
   display: none;
 }
@@ -81,8 +70,6 @@
 
 /* TODO: we should be able to use notebook styles for this */
 .jp-Chatbox-input .jp-Chatbox-prompt.jp-Cell {
-  background: transparent;
-  border-color: #66BB6A;
   border-left-width: var(--jp-border-width);
 }