diff --git a/web/account/log-in-form.react.js b/web/account/log-in-form.react.js
--- a/web/account/log-in-form.react.js
+++ b/web/account/log-in-form.react.js
@@ -127,6 +127,13 @@
     return 'Log in';
   }, [inputDisabled]);
 
+  const loginButtonColor = React.useMemo(
+    () => ({
+      backgroundColor: '#6A20E3',
+    }),
+    [],
+  );
+
   let siwe;
   if (isDev) {
     siwe = <SIWE />;
@@ -165,6 +172,7 @@
             type="submit"
             disabled={inputDisabled}
             onClick={onSubmit}
+            buttonColor={loginButtonColor}
           >
             {loginButtonContent}
           </Button>
diff --git a/web/account/siwe.react.js b/web/account/siwe.react.js
--- a/web/account/siwe.react.js
+++ b/web/account/siwe.react.js
@@ -138,6 +138,13 @@
     attemptSIWEAuth(message, signature);
   }, [address, attemptSIWEAuth, primaryIdentityPublicKey, signer, siweNonce]);
 
+  const signInButtonColor = React.useMemo(
+    () => ({
+      backgroundColor: '#6A20E3',
+    }),
+    [],
+  );
+
   let siweLoginForm;
   if (signer && (!siweNonce || !primaryIdentityPublicKey)) {
     siweLoginForm = (
@@ -158,7 +165,11 @@
           <a href="https://comm.app/terms">Terms of Use</a> &{' '}
           <a href="https://comm.app/privacy">Privacy Policy</a>.
         </p>
-        <Button variant="filled" onClick={onSignInButtonClick}>
+        <Button
+          variant="filled"
+          onClick={onSignInButtonClick}
+          buttonColor={signInButtonColor}
+        >
           Sign in
         </Button>
       </div>