Update readme

Author: gonuit

README.md

@@ -60,8 +60,8 @@ Almost all of these examples are available in the example application.
 |                                           ![plane_indicator](readme/plane_indicator.gif)                                           |                                        ![ice_cream_indicator](readme/ice_cream_indicator.gif)                                        |                                     ![warp_indicator](readme/warp_indicator.gif)                                      |
 
 | With complete state [[SOURCE](example/lib/indicators/check_mark_indicator.dart)][[DEMO](https://custom-refresh-indicator.klyta.it/#/check-mark)] | Pull to fetch more [[SOURCE](example/lib/indicators/swipe_action.dart)][[DEMO](https://custom-refresh-indicator.klyta.it/#/fetch-more)] | Envelope [[SOURCE](example/lib/indicators/envelope_indicator.dart)][[DEMO](https://custom-refresh-indicator.klyta.it/#/envelope)] |
-| :----------------------------------------------------------------------------------------------------------------------------------------------: | :-------------------------------------------------------------------------------------------------------------------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------: |
-|                                    ![indicator_with_complete_state](readme/indicator_with_complete_state.gif)                                    |                                                  ![fetch_more](readme/fetch_more.gif)                                                   |                                            ![Envelope indicator](readme/envelope_indicator.gif)                                             |
+| :----------------------------------------------------------------------------------------------------------------------------------------------: | :-------------------------------------------------------------------------------------------------------------------------------------: | :-------------------------------------------------------------------------------------------------------------------------------: |
+|                                    ![indicator_with_complete_state](readme/indicator_with_complete_state.gif)                                    |                                                  ![fetch_more](readme/fetch_more.gif)                                                   |                                       ![Envelope indicator](readme/envelope_indicator.gif)                                        |
 
 | Programmatically controlled [[SOURCE](example/lib/screens/programmatically_controlled_indicator_screen.dart)][[DEMO](https://custom-refresh-indicator.klyta.it/#/programmatically-controlled)] |                                                                 Your indicator                                                                  |                                                                 Your indicator                                                                  |
 | :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------: | :---------------------------------------------------------------------------------------------------------------------------------------------: |
@@ -102,7 +102,9 @@ CustomRefreshIndicator(
 
 The best way to understand how the _CustomRefreshIndicator_ widget changes its controller data is to see the example 😉. An example is available in the example application.
 
-![Controller_Data](readme/controller_data.gif)
+<div align="center">
+  <img width="300px" src="readme/controller_data.gif" />
+<div>
 
 | state        | value   | value description                                                                                       | Description                                                                                                                                                                                                                              |
 | ------------ | :------ | :------------------------------------------------------------------------------------------------------ | :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |