Make demo button larger

Author: Daniel Precioso

_pages/about.md

@@ -94,7 +94,7 @@ The goal is both to improve the state of the art algorithms for weather routing,
 
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-<a href="https://demo.weathernavigation.com/" class="button" style="background-color: #00376D; color: #FFFFFF;">Demo</a>
+<a href="https://demo.weathernavigation.com/" class="button" style="background-color: #00376D; color: #FFFFFF; width: 100%;">Demo</a>
 
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