A birdcage (or bird cage) is a cage designed to house birds as pets. Antique (or antique-style) birdcages are often popular as collectors' items or as household decor but most are not suitable for housing live birds, being too small, or of unsafe materials or construction.ood quality cages designed for pet birds are more suitable. Most parrot cages are made or wrought iron and painted with a non-toxic paint referred to as powder-coating. However, the newest trend in the market is cages made of solid stainless steel.
A viewport is a 2D rectangle that defines the size of the rendering surface onto which a 3D scene is projected.
If the user resizes the browser then the script runs again to resize the elements on the page. With vw/vh, we can size elements to be relative to the size of the viewport. The vw/vh units are interesting in that 1 unit reflects 1/100th the width of the viewport. To make an element the full width of the viewport, for example, you'd set it to width:100vw.