ui: drop blueprintjs 6 (#1073)

packages/ui-default/pages/problem_config.page.styl

@@ -1,50 +1,14 @@
 .page--problem_config
+  .main
+    .row
+      max-width: 100vw !important;
+
   .textbox,.select
     margin: 0
-  
-  .bp6-tab-panel
-    margin-top: 5px
-
-  .bp6-dialog
-    font-family: var(--code-font-family)
-    background: #fff
-
-    .autocomplete-container
-      font-size: 0.875rem
-      color: #666
-
-    .bp6-dialog-footer-fixed
-      border-top: 0
-
-      .button
-        margin: 0
 
   input::placeholder
     color: rgba(95,107,124,.6)!important
 
-  .bp6-input-group
-    input
-      appearance: none
-      display: block
-      width: 100%
-      font-size: 0.875rem
-      height: 2.1875rem
-      line-height: 1.2
-      padding: 0.3125rem;
-      border: 1px solid #ddd
-      color: inherit
-      border-radius: 0
-      outline: 2px solid transparent
-      transition: outline-color 0.2s, border-color 0.2s
-      transition-timing-function: cubic-bezier(0.215, 0.61, 0.355, 1)
-      box-shadow: none
-
-  .bp6-tag.bp6-minimal
-    background: transparent
-  
-  .bp6-input-action
-      pointer-events: none
-
   .problem-config-form
     font-family: var(--code-font-family)
   
@@ -55,4 +19,3 @@
 
   .hover-row.status-bar
     display: none
-