diff --git a/in/en/index.html b/in/en/index.html
index 2c87fea..44b34df 100644
--- a/in/en/index.html
+++ b/in/en/index.html
@@ -340,6 +340,7 @@
 <h1 class="title">DevOps</h1>
 <p class="sub">@ <a href="https://en.wikipedia.org/wiki/Ministry_of_Armed_Forces_(France)">Ministry of Armed Forces (France)</a></p>
 </div>
+<button id="swap">↔</button>
 </header>
 <ul>Always curious about Information Technology, exploring & automating:
 <li>booting, building, configuring, securing, maintaining <strong>Linux</strong> systems</li>
diff --git a/in/fr/index.html b/in/fr/index.html
index bc642c9..0b75273 100644
--- a/in/fr/index.html
+++ b/in/fr/index.html
@@ -340,6 +340,7 @@
 <h1 class="title">DevOps</h1>
 <p class="sub">@ <a href="https://fr.wikipedia.org/wiki/Ministère_des_Armées">Ministère des Armées</a></p>
 </div>
+<button id="swap">↔</button>
 </header>
 <ul>Toujours curieux des technologies informatiques, explorant et automatisant :
 <li>amorçage, construction, configuration, sécurisation, maintien de systèmes <strong>Linux</strong></li>
diff --git a/in/style/main.css b/in/style/main.css
index a6eec19..98b85e1 100644
--- a/in/style/main.css
+++ b/in/style/main.css
@@ -54,7 +54,7 @@
 
 /* main */
 
-#link, #theme {
+#link, #theme, #swap {
     background-color: var(--button-background);
 }
 #vcard {