diff --git a/cssmin.php b/cssmin.php
index 5829937..1388bc1 100644
--- a/cssmin.php
+++ b/cssmin.php
@@ -598,7 +598,7 @@ private function preserve_old_IE_specific_matrix_definition($matches)
 
 	private function replace_keyframe_zero($matches)
     {
-        return $matches[1] . preg_replace('/0(\{|,[^\{]+\{)/', '0%$1', $matches[2]) . $matches[3];
+        return $matches[1] . preg_replace('/0(\{|,[^\)\{]+\{)/', '0%$1', $matches[2]) . $matches[3];
     }
 
     private function rgb_to_hex($matches)
diff --git a/tests/mine/keyframes.css b/tests/mine/keyframes.css
index f30a8fa..0a66824 100644
--- a/tests/mine/keyframes.css
+++ b/tests/mine/keyframes.css
@@ -18,4 +18,5 @@
 }
 @-webkit-keyframes test4{
     0% { transform: rotate3d(0,0,1,30deg); }
+    100% { transform: rotate3d(0,0,1,10deg); }
 }
\ No newline at end of file
diff --git a/tests/mine/keyframes.css.min b/tests/mine/keyframes.css.min
index 1df43bb..b03ffd2 100644
--- a/tests/mine/keyframes.css.min
+++ b/tests/mine/keyframes.css.min
@@ -1 +1 @@
-@keyframes anim{0%{opacity:0}100%{opacity:1}}@-o-keyframes anim{0%{opacity:0}100%{opacity:1}}@keyframes test{0%,100%{opacity:0}}@keyframes test2{0%,100%{opacity:0}}@keyframes test3{50%{opacity:50}100%,0%{opacity:0}}@-webkit-keyframes test4{0%{transform:rotate3d(0,0,1,30deg)}}
\ No newline at end of file
+@keyframes anim{0%{opacity:0}100%{opacity:1}}@-o-keyframes anim{0%{opacity:0}100%{opacity:1}}@keyframes test{0%,100%{opacity:0}}@keyframes test2{0%,100%{opacity:0}}@keyframes test3{50%{opacity:50}100%,0%{opacity:0}}@-webkit-keyframes test4{0%{transform:rotate3d(0,0,1,30deg)}100%{transform:rotate3d(0,0,1,10deg)}}
\ No newline at end of file