--- layout: docs title: Sizing and positioning group: utilities --- ## Fixed positioning The `.pos-f-t` class can be used to easily position elements at the top of the viewport and make them as wide as the viewport. **Be sure you understand the ramifications of fixed-position elements within your project.** Here's how the class is defined: {% highlight scss %} .pos-f-t { position: fixed; top: 0; right: 0; left: 0; z-index: $zindex-navbar-fixed; } {% endhighlight %} ## Width and height Easily make an element as wide or as tall (relative to its parent) with our width and height utilities. Includes support for `25%`, `50%`, `75%`, and `100%`. {% example html %}
Width 25%
Width 50%
Width 75%
Width 100%
{% endexample %} {% example html %}
Height 25%
Height 50%
Height 75%
Height 100%
{% endexample %} You can also use `max-width: 100%;` and `max-height: 100%;` utilities as needed. {% example html %} Max-width 100% {% endexample %} {% example html %}
Max-height 100%
{% endexample %}