diff --git a/docs/_static/custom.css b/docs/_static/custom.css
index efc9b1ade3e8b465565e494a2f932b9f4a274617..5efaa860974c918d13a49ed0ff3b9273d66ec21f 100644
--- a/docs/_static/custom.css
+++ b/docs/_static/custom.css
@@ -1,15 +1,3 @@
-html[data-theme="light"] {
-  --pst-color-primary: #e20026;
-  --pst-color-secondary: #52566D;
-}
-
-html[data-theme="dark"] {
-  --pst-color-primary: #e20026;
-  --pst-color-secondary: #dbdbdb;
-  --pst-color-secondary-text: #141325;
-}
-
-
 table.swh-logos-table td,
 table.swh-logos-table th {
   text-align: center;
diff --git a/docs/index.rst b/docs/index.rst
index 0eabce272747a84a85de1bf5f05f7d08c069e6dc..4c77e6d8e15948dc429ab24450c9c42f9f658bf6 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -24,7 +24,7 @@ Welcome to Software Heritage documentation
 
       .. button-ref:: landing-basics
          :ref-type: ref
-         :color: secondary
+         :color: primary
          :expand:
 
          Discover Software Heritage
@@ -41,7 +41,7 @@ Welcome to Software Heritage documentation
 
       .. button-ref:: landing-preserve
          :ref-type: ref
-         :color: secondary
+         :color: primary
          :expand:
 
          Archive source code
@@ -59,7 +59,7 @@ Welcome to Software Heritage documentation
 
       .. button-ref:: landing-browse
          :ref-type: ref
-         :color: secondary
+         :color: primary
          :expand:
 
          Learn how to search the archive
@@ -76,7 +76,7 @@ Welcome to Software Heritage documentation
       Join our network of partners. Collaborate with the team or become an ambassador. Teach others how to use the archive. Get materials for your next events.
 
       .. button-link:: http://example.com
-         :color: secondary
+         :color: primary
          :expand:
 
          Tell the world about Software Heritage
@@ -94,7 +94,7 @@ Welcome to Software Heritage documentation
 
       .. button-ref:: landing-interface
          :ref-type: ref
-         :color: secondary
+         :color: primary
          :expand:
 
          Use Software Heritage in your applications
@@ -112,7 +112,7 @@ Welcome to Software Heritage documentation
 
       .. button-ref:: landing-contribute
          :ref-type: ref
-         :color: secondary
+         :color: primary
          :expand:
 
          Improve the universal archive of source code