Improve form filter style

app/assets/stylesheets/forms.css.scss

@@ -12,9 +12,11 @@
 }
 
 .filter-form {
-  .form-group {
+  .row:not(:last-child) {
     margin-bottom: 1em;
+  }
 
+  .form-group {
     &:not(:last-child) {
       margin-right: 1em;
     }

app/views/exercises/index.html.slim

@@ -1,6 +1,7 @@
 h1 = Exercise.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:execution_environment_id_eq, t('activerecord.attributes.exercise.execution_environment'), class: 'sr-only')
       = f.collection_select(:execution_environment_id_eq, ExecutionEnvironment.with_exercises, :id, :name, class: 'form-control', prompt: t('activerecord.attributes.exercise.execution_environment'))

app/views/internal_users/index.html.slim

@@ -1,6 +1,7 @@
 h1 = InternalUser.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:consumer_id_eq, t('activerecord.attributes.internal_user.consumer'), class: 'sr-only')
       = f.collection_select(:consumer_id_eq, Consumer.with_internal_users, :id, :name, class: 'form-control', prompt: t('activerecord.attributes.internal_user.consumer'))

app/views/proxy_exercises/index.html.slim

@@ -1,6 +1,7 @@
 h1 = ProxyExercise.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:title_cont, t('activerecord.attributes.proxy_exercise.title'), class: 'sr-only')
       = f.search_field(:title_cont, class: 'form-control', placeholder: t('activerecord.attributes.proxy_exercise.title'))

app/views/request_for_comments/index.html.slim

@@ -1,6 +1,7 @@
 h1 = RequestForComment.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:exercise_title_cont, t('activerecord.attributes.request_for_comments.exercise'), class: 'sr-only')
       = f.search_field(:exercise_title_cont, class: 'form-control', placeholder: t('activerecord.attributes.request_for_comments.exercise'))

app/views/study_groups/index.html.slim

@@ -1,6 +1,7 @@
 h1 = StudyGroup.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:consumer_id_eq, t('activerecord.attributes.internal_user.consumer'), class: 'sr-only')
       = f.collection_select(:consumer_id_eq, Consumer.with_study_groups, :id, :name, class: 'form-control', prompt: t('activerecord.attributes.internal_user.consumer'))

app/views/submissions/index.html.slim

@@ -1,6 +1,7 @@
 h1 = Submission.model_name.human(count: 2)
 
 = render(layout: 'shared/form_filters') do |f|
+  .row.px-3
     .form-group
       = f.label(:exercise_id_eq, t('activerecord.attributes.submission.exercise'), class: 'sr-only')
       = f.collection_select(:exercise_id_eq, Exercise.with_submissions, :id, :title, class: 'form-control', prompt: t('activerecord.attributes.submission.exercise'))