diff --git a/src/shader/fragment.frag b/src/shader/fragment.frag
index 57f1ac4..ba79551 100644
--- a/src/shader/fragment.frag
+++ b/src/shader/fragment.frag
@@ -2,10 +2,8 @@
 
 uniform sampler2D font_sampler;
 
-in vec2 f_tex_pos;
-in vec4 f_color;
-
-varying out vec4 Target0;
+varying vec2 f_tex_pos;
+varying vec4 f_color;
 
 void main() {
     float alpha = texture2D(font_sampler, f_tex_pos).r;
@@ -14,5 +12,5 @@ void main() {
         discard;
     }
 
-    Target0 = f_color * vec4(1.0, 1.0, 1.0, alpha);
+    gl_FragColor = f_color * vec4(1.0, 1.0, 1.0, alpha);
 }
diff --git a/src/shader/vertex.vert b/src/shader/vertex.vert
index 0a24b7d..f6685ff 100644
--- a/src/shader/vertex.vert
+++ b/src/shader/vertex.vert
@@ -2,9 +2,9 @@
 
 uniform mat4 transform;
 
-in vec2 tex_pos;
-in vec3 pos;
-in vec4 color;
+attribute vec2 tex_pos;
+attribute vec3 pos;
+attribute vec4 color;
 
 varying vec2 f_tex_pos;
 varying vec4 f_color;