diff --git a/sphinx/themes/basic/static/basic.css_t b/sphinx/themes/basic/static/basic.css_t
index 5c3a3a78987..6640cccbe0f 100644
--- a/sphinx/themes/basic/static/basic.css_t
+++ b/sphinx/themes/basic/static/basic.css_t
@@ -15,6 +15,12 @@ div.clearer {
     clear: both;
 }
 
+div.section::after {
+    display: block;
+    content: '';
+    clear: left;
+}
+
 /* -- relbar ---------------------------------------------------------------- */
 
 div.related {
@@ -376,6 +382,15 @@ div.admonition > :last-child {
     margin-bottom: 0;
 }
 
+div.sidebar::after,
+div.topic::after,
+div.admonition::after,
+blockquote::after {
+    display: block;
+    content: '';
+    clear: both;
+}
+
 /* -- tables ---------------------------------------------------------------- */
 
 table.docutils {