fix: restore rounded corners except on cards, buttons and inputs, and lighten dark-mode text colours

pipeline/source_assets/scss/_custom-variables.scss

@@ -2,7 +2,6 @@ $font-family-sans-serif: "Open Sans", sans-serif;
 //Make it look less primary school
 $font-size-base: 0.85rem;
 $enable-shadows: true;
-$enable-rounded: false;
 
 $primary: #3A52A2;
 $success: #5cb85c;

pipeline/source_assets/scss/screen.scss

@@ -311,7 +311,8 @@ html.embedded {
   }
 }
 
-.CodeMirror, .editor-toolbar {
+// The site has always used square cards, buttons and inputs; everything else keeps Bootstrap's rounding
+.card, .card-header, .btn, input, select, .CodeMirror, .editor-toolbar, .card-img-top {
     border-radius: 0 !important;
 }
 
@@ -354,6 +355,12 @@ $dark-theme-colors: (
         .btn-outline-#{$name} {
             @include button-outline-variant($value);
         }
+        // The brand colours above are tuned for backgrounds; text needs the lighter emphasis shade to be legible
+        @if $name != "light" and $name != "dark" {
+            .text-#{$name} {
+                color: var(--bs-#{$name}-text-emphasis) !important;
+            }
+        }
         .text-bg-#{$name} {
             color: color-contrast($value) !important;
             background-color: RGBA(to-rgb($value), var(--bs-bg-opacity, 1)) !important;