Improve light theme

Author: Gargron

app/javascript/mastodon/features/list_timeline/index.js

@@ -175,8 +175,6 @@ class ListTimeline extends React.PureComponent {
               <Icon id='trash' /> <FormattedMessage id='lists.delete' defaultMessage='Delete list' />
             </button>
           </div>
-
-          <hr />
         </ColumnHeader>
 
         <StatusListContainer

app/javascript/mastodon/features/lists/index.js

@@ -65,11 +65,11 @@ class Lists extends ImmutablePureComponent {
 
         <NewListForm />
 
-        <ColumnSubheading text={intl.formatMessage(messages.subheading)} />
         <ScrollableList
           scrollKey='lists'
           shouldUpdateScroll={shouldUpdateScroll}
           emptyMessage={emptyMessage}
+          prepend={<ColumnSubheading text={intl.formatMessage(messages.subheading)} />}
         >
           {lists.map(list =>
             <ColumnLink key={list.get('id')} to={`/timelines/list/${list.get('id')}`} icon='list-ul' text={list.get('title')} />