diff --git a/c3.css b/c3.css
index c1b0abb..b8e8917 100644
--- a/c3.css
+++ b/c3.css
@@ -6,7 +6,6 @@
 .c3 path, .c3 line {
   fill: none;
   stroke: #000;
-  stroke-width: 1px;
 }
 .c3 text {
   -webkit-user-select: none;