diff --git a/script.js b/script.js
index 291fc87..320fb41 100644
--- a/script.js
+++ b/script.js
@@ -67,10 +67,24 @@ function getContrastColor(hex) {
     return yiq >= 128 ? '#000' : '#fff';
 }
 
+function lightenColor(hex, percent) {
+    if (!hex) return '#fff';
+    let c = hex.replace('#','');
+    if (c.length === 3) c = c.split('').map(x=>x+x).join('');
+    let r = parseInt(c.substr(0,2),16);
+    let g = parseInt(c.substr(2,2),16);
+    let b = parseInt(c.substr(4,2),16);
+    r = Math.min(255, Math.round(r + (255 - r) * percent));
+    g = Math.min(255, Math.round(g + (255 - g) * percent));
+    b = Math.min(255, Math.round(b + (255 - b) * percent));
+    return '#' + [r,g,b].map(x=>x.toString(16).padStart(2,'0')).join('');
+}
+
 function applyEventColors(elem, color, alpha) {
     if (!color || !elem) return;
     elem.style.setProperty('--bg-color', hexToRgba(color, alpha));
-    elem.style.setProperty('--border-color', color);
+    // Use a lighter shade for the border so it stands out even for dark colors
+    elem.style.setProperty('--border-color', lightenColor(color, 0.4));
     elem.style.setProperty('--text-color', getContrastColor(color));
 }