Ensure consistent appearance of btn-link

After migrating `link_to` to `button_to` (in the previous commit), we need to adjust the styles for a uniform and correct appearance.

Author: MrSerth

app/assets/stylesheets/base.css.scss

@@ -51,7 +51,7 @@ span.caret {
   margin-left: 0.5em;
 }
 
-.btn {
+.btn:not(.btn-link) {
   -webkit-font-smoothing: antialiased;
   font-weight: 500;
   :not(.btn-lg) {

app/assets/stylesheets/editor.css.scss

@@ -96,15 +96,19 @@ html[data-bs-theme="light"] {
   display: none;
 }
 
-#statusbar{
+#statusbar {
   visibility: hidden;
   margin-top: .2em;
   height: 1.6em;
   color: var(--bs-tertiary-color);
-  font-size: 0.8em;
+  font-size: 0.8rem;
 }
 
-#turtlecanvas{
+.btn-statusbar {
+  --bs-btn-font-size: 0.8rem;
+}
+
+#turtlecanvas {
   border-style:solid;
   border-width:thin;
   display: block;

app/javascript/stylesheets.scss

@@ -40,6 +40,15 @@ html[data-bs-theme="light"] {
   }
 }
 
+
+// Match the button styles for .btn-link to regular links.
+.btn-link {
+  @extend .p-0;
+  @extend .border-0;
+  @extend .align-baseline;
+}
+
+
 $fa-font-path: '@fortawesome/fontawesome-free/webfonts/';
 @import '@fortawesome/fontawesome-free/scss/fontawesome';
 @import '@fortawesome/fontawesome-free/scss/solid';

app/views/execution_environments/shell.html.slim

@@ -20,7 +20,7 @@ h1 = @execution_environment
       .card-body.pt-0.pe-0.ps-1.pb-1
         #download-file-tree.justify-content-center.d-flex.my-3
           span.mx-1 = t('execution_environments.shell.file_tree.empty')
-          button#reload-now-link.btn.btn-link.p-0.m-0.border-0 = t('execution_environments.shell.file_tree.list_now')
+          button#reload-now-link.btn.btn-link = t('execution_environments.shell.file_tree.list_now')
       - unless @execution_environment.privileged_execution?
         .card-footer.justify-content-center.align-items-center.d-flex.text-body-secondary
           i.fa-solid.fa-info

app/views/exercises/_editor.html.slim

@@ -33,7 +33,7 @@
     #statusbar.d-flex.justify-content-between
       div
         - if !@embed_options[:disable_download] && @exercise.hide_file_tree?
-          button#download.p-0.border-0.btn-link.visible.bg-body.text-primary
+          button#download.btn.btn-link.btn-statusbar.visible
             i.fa-solid.fa-arrow-down
             = t('exercises.editor.download')
 
@@ -55,7 +55,7 @@
 
         = ' | '
 
-        button#start-over-active-file.p-0.border-0.btn-link.bg-body.text-primary data-message-confirm=t('exercises.editor.confirm_start_over_active_file') data-url=reload_exercise_path(@exercise)
+        button#start-over-active-file.btn.btn-link.btn-statusbar data-message-confirm=t('exercises.editor.confirm_start_over_active_file') data-url=reload_exercise_path(@exercise)
           i.fa-solid.fa-circle-notch.fa-spin.d-none
           i.fa-solid.fa-clock-rotate-left
           = t('exercises.editor.start_over_active_file')