app/src/main/res/values/dimens.xml
<resources>
<!-- Default screen margins, per the Android Design guidelines. -->
<dimen name="activity_horizontal_margin">16dp</dimen>
<dimen name="activity_vertical_margin">16dp</dimen>
<dimen name="nav_header_vertical_spacing">8dp</dimen>
<dimen name="nav_header_height">176dp</dimen>
<dimen name="fab_margin">16dp</dimen>
<dimen name="text_margin">16dp</dimen>
</resources>