diff --git a/tests/test_theme_agent.py b/tests/test_theme_agent.py
new file mode 100644
index 0000000..482ab33
--- /dev/null
+++ b/tests/test_theme_agent.py
@@ -0,0 +1,28 @@
+"""Thème du site (#49) : Kanbante doit ressembler à la console
+agent / barre Fusion (draco-barre, Console v7.2), pas au bleu/mauve
+historique. Le test fige les jetons et interdit le retour des
+littéraux violet/bleu de thème dans style.css.
+"""
+
+
+def test_theme_agent_tokens(client, fake_gitea):
+    css = client.get("/static/css/style.css").text
+    assert "--bg: #101211;" in css
+    assert "--surface: #1a1c1a;" in css
+    assert "--surface-2: #242624;" in css
+    assert "--surface-3: #20221f;" in css
+    assert "--border: #2e302c;" in css
+    assert "--text: #eceee9;" in css
+    assert "--accent: #c2437e;" in css
+    assert "--accent-2: #e078a8;" in css
+
+
+def test_no_blue_purple_theme_literals(client, fake_gitea):
+    css = client.get("/static/css/style.css").text
+    for banned in (
+        "#7c5cfc", "#5b8af7", "#58a6ff", "#a78bfa", "#7dd3fc",
+        "#c4b5fd", "#a5c4fd", "#0b0e14", "#141822", "#1b202e",
+        "#232939", "124, 92, 252", "124,92,252",
+        "91, 138, 247", "91,138,247",
+    ):
+        assert banned not in css, banned