DOC Reduce whitespace above h1 tag (scikit-learn#26787)

Co-authored-by: Gael Varoquaux <[email protected]>

Author: 2 people

doc/themes/scikit-learn-modern/static/css/theme.css

@@ -661,13 +661,19 @@ div.sk-sidebar-global-toc ul ul {
 div.sk-page-content h1 {
   background-color: #cde8ef;
   padding: 0.5rem;
-  margin-top: calc(max(2.5rem, 1vh));
+  margin-top: calc(max(1rem, 1vh));
   border-radius: 0 1rem;
   text-align: center;
   font-size: 2rem;
   word-wrap: break-word;
 }
 
+/* General sibling selector: does not apply to first h1, to avoid gap in
+ * top of page */
+div.sk-page-content ~ h1 {
+    margin-top: calc(max(2.5rem, 1vh));
+}
+
 div.sk-page-content h2 {
   padding: 0.5rem;
   background-color: #BED4EB;