Centering a block or image. Sometimes it is not the text that needs to be centered, but the block as a whole. Or, phrased differently: we want the left and right margin to be equal. The way to do that is to set the margins to 'auto'.In case of a browser, that means the browser window). So centering an element in the viewport is very simple. Here is a complete example. (This example uses HTML5 syntax.). You can see the result in a separate document. The 'margin-right: -50%' is needed to compensate the 'left: 50%'.
Slugs and snails share many similar features. However, the most apparent difference between the two is that snails carry coiled shells on their backs whereas slugs do not contain these shells. A shell of snail is composed of calcium carbonate and it keeps growing with the growth of snail.Both produce mucous for retaining the moisture.owever, the most apparent difference between the two is that snails carry coiled shells on their backs whereas slugs do not contain these shells. A shell of snail is composed of calcium carbonate and it keeps growing with the growth of snail. Both produce mucous for retaining the moisture.
Some examples of invertebrates are mollusks -- snail, mussel, quahog, squid, octopus, nautilus --, echinoderms -- starfish and sea urchins --, arachnids, crustaceans -- lobsters and crabs --, all insects, annelids -- worms and leeches -- protozoa and jellyfish. The main difference between.are that vertebrates have backbones, while invertebrates do not. Other differences are that vertebrates have highly developed brains, while most invertebrates do not.nvertebrates are slow moving, and sometimes small, while most vertebrates are faster, and sometimes larger in size than invertebrates. 98% of animal species are invertebrates, meaning that 2% of animal species are vertebrates.