diff --git a/src/utils.rs b/src/utils.rs
index db182a99..3a48628e 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -341,7 +341,11 @@ impl Style {
                 "reverse" => rv.reverse(),
                 "hidden" => rv.hidden(),
                 "strikethrough" => rv.strikethrough(),
-                on_true_color if on_true_color.starts_with("on_#") && on_true_color.len() == 10 => {
+                on_true_color
+                    if on_true_color.starts_with("on_#")
+                        && on_true_color.len() == 10
+                        && on_true_color.is_ascii() =>
+                {
                     if let (Ok(r), Ok(g), Ok(b)) = (
                         u8::from_str_radix(&on_true_color[4..6], 16),
                         u8::from_str_radix(&on_true_color[6..8], 16),
@@ -352,7 +356,11 @@ impl Style {
                         continue;
                     }
                 }
-                true_color if true_color.starts_with('#') && true_color.len() == 7 => {
+                true_color
+                    if true_color.starts_with('#')
+                        && true_color.len() == 7
+                        && true_color.is_ascii() =>
+                {
                     if let (Ok(r), Ok(g), Ok(b)) = (
                         u8::from_str_radix(&true_color[1..3], 16),
                         u8::from_str_radix(&true_color[3..5], 16),
@@ -1195,3 +1203,27 @@ fn test_attributes_many() {
         assert_eq!(&attrs.attrs().collect::<Vec<_>>(), test_attrs);
     }
 }
+
+#[test]
+fn test_style_from_non_ascii_fg() {
+    // len() == 7, starts_with('#'), but slices [1..3] land mid-€ (3 bytes)
+    let fg = "#€€";
+    assert_eq!(fg.len(), 7);
+
+    let parsed_style = Style::from_dotted_str(fg);
+
+    // silently ignores non-ascii
+    assert_eq!(parsed_style, Style::default());
+}
+
+#[test]
+fn test_style_from_non_ascii_bg() {
+    // len() == 10, starts_with("on_#"), but slices [4..6] land mid-€
+    let bg = "on_#€€";
+    assert_eq!(bg.len(), 10);
+
+    let parsed_style = Style::from_dotted_str(bg);
+
+    // silently ignores non-ascii
+    assert_eq!(parsed_style, Style::default());
+}