diff --git a/lib/tinycolor.dart b/lib/tinycolor.dart
index 06e429d..d5ef743 100644
--- a/lib/tinycolor.dart
+++ b/lib/tinycolor.dart
@@ -23,8 +23,11 @@ class TinyColor {
         Color.fromARGB(color.alpha, color.red, color.green, color.blue);
   }
 
-  factory TinyColor.fromRGB(
-      {@required int r, @required int g, @required int b, int a = 100}) {
+  factory TinyColor.fromRGB({
+    // default alpha should be 255, not 100
+    // since Color.fromARGB accept alpha range values 0-255, not 0-100
+    @required int r, @required int g, @required int b, int a = 255,
+  }) {
     return TinyColor(Color.fromARGB(a, r, g, b));
   }
 
@@ -143,12 +146,14 @@ class TinyColor {
   }
 
   TinyColor mix({@required Color input, int amount = 50}) {
-    final int p = (amount / 100).round();
+    final double p = (amount / 100);
     final color = Color.fromARGB(
-        (input.alpha - _color.alpha) * p + _color.alpha,
-        (input.red - _color.red) * p + _color.red,
-        (input.green - _color.green) * p + _color.green,
-        (input.blue - _color.blue) * p + _color.blue);
+      ((input.alpha - _color.alpha) * p).round() + _color.alpha,
+      ((input.red - _color.red) * p).round() + _color.red,
+      ((input.green - _color.green) * p).round() + _color.green,
+      ((input.blue - _color.blue) * p).round() + _color.blue,
+    );
+    
     return TinyColor(color);
   }
 
diff --git a/pubspec.lock b/pubspec.lock
index 544bf47..7cfe175 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -68,7 +68,7 @@ packages:
     source: hosted
     version: "0.12.8"
   meta:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: meta
       url: "https://pub.dartlang.org"
diff --git a/pubspec.yaml b/pubspec.yaml
index 1bb06c5..14c9a97 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -8,10 +8,11 @@ environment:
   flutter: ">=1.12.0 <3.0.0"
 
 dependencies:
-  pigment: ^1.0.3
-  meta: ^1.2.2
   flutter:
     sdk: flutter
+  
+  pigment: ^1.0.3
+  meta: ^1.1.8
 
 dev_dependencies:
   flutter_test: