diff --git a/copyparty/web/browser.css b/copyparty/web/browser.css
index 5026888a..76839833 100644
--- a/copyparty/web/browser.css
+++ b/copyparty/web/browser.css
@@ -2148,6 +2148,9 @@ html.y #tree.nowrap .ntree a+a:hover {
 #rui td input[type="text"] {
 	width: 100%;
 }
+input[type="text"].invalid {
+	border-color: var(--err-b1);
+}
 #rui #rn_n_d,
 #rui #rn_n_s,
 #shui td.exs input[type="text"] {
diff --git a/copyparty/web/browser.js b/copyparty/web/browser.js
index 484977fc..6c3e5fed 100644
--- a/copyparty/web/browser.js
+++ b/copyparty/web/browser.js
@@ -1275,18 +1275,27 @@ ebi('op_cfg').innerHTML = (
 })();
 
 // accent color
+function parseColor (strColor) {
+  const s = new Option().style;
+  s.color = strColor;
+  return s.color !== '' ? s.color : '';
+}
+
 ebi('accent').oninput = function () {
-	if(this.value == accent) 
+	var validcolor = parseColor(this.value);
+	clmod(ebi('accent'), 'invalid', this.value.length != 0 && validcolor.length == 0);
+	if(validcolor == accent) 
 		return;
-	accent = this.value;
+	accent = validcolor;
 	swrite('accent', accent);
 	var a = accent || '#fc0';
 	console.log('accent color set to: ' + a);
 	document.documentElement.style.setProperty('--a', a);
 }
-var accent = ebi('accent').value = sread('accent') || '';
-if(accent)
-	document.documentElement.style.setProperty('--a', accent);
+var accent = ebi('accent').value = sread('accent');
+if(accent){
+	document.documentElement.style.setProperty('--a', parseColor(accent));
+}
 
 // navpane
 ebi('tree').innerHTML = (